SESSION I Dissolved Organic Matter (DOM)

SESSION I Dissolved Organic Matter (DOM): Formation, turnover, degradation and properties MAREN SEIBT1, TANJA STRATMANN2, MAREN STUMM1 1

Max-Planck-Research Group for Marine Geochemistry, Institute for Chemistry and Biology of the Marine Environment, Carl-von- Ossietzky-Strasse 9-11, 26129 Oldenburg, Germany 2

Department of Bioscience – Marine Ecology, University of Aarhus, Frederiksborgvej 399, 4000 Roskilde, Denmark Abstract The amount of carbon bound in dissolved organic matter (DOM) in the global oceans equals the quantity of carbon in the form of atmospheric CO 2. That is why it is a major component of the global carbon cycle and serves as both nutrient as well as energy source for microbial life. The shape of the DOM pool is modified via various biotic and abiotic processes, e.g. microbial turnover, phytoplankton blooms, riverine input of terrestrial material, hydrothermal systems in the deep ocean, solar radiation at the surface or ocean acidification. Emerging analytical techniques from various fields of biogeochemistry and oceanography in combination with interdisciplinary approaches allow us to obtain detailed insights to the composition and properties, formation, turnover and degradation of dissolved organic matter. Therefore, this session will bring together different scale and disciplinary approaches of DOM research, aiming at a better understanding of the fate of DOM in the global oceans.

Session I Dissolved Organic Matter (DOM): Formation, turnover, degradation and properties

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Contents Talks [including time slots] Osterholz et al. [12.9.2013; 11.10 am] INVITED SPEAKER Fast production of diverse dissolved organic matter by a natural microbial community Dubinenkov et al. [12.9.2013; 11:25 am] Origin-specific molecular markers of dissolved organic matter in the Lena Delta Schwieder and Gärdes [12.9.2013; 11:40 am] Seasonal bacteria-driven organic matter export along a tropical eutrophication gradient. Das and Ramanathan [12.9.2013; 11:55 am] Variation of DOC in surface waters of Bhitarkanika Mangroves, India Röder et al. [12.9.2013; 12:10 am] Empirical reconstruction of correlations and directed relations within dissolved organic matter Zakrisson et al. [12.9.2013; 12:25 am] Effects of combined nitrogen on nitrogen fixation and biomass development of Baltic Sea Aphanizomenon sp.

Poster [including poster number] Köster et al. [DOM1] Short-term dynamics of dissolved organic matter and bacterial communities Stratmann and Lund-Hansen [DOM2] CDOM in the Central Arctic surface waters and sea ice Pohlabeln et al. [DOM3] Dissolved organic sulfur in the ocean – structural investigations via FT-ICR-MS Hoffmann and Laudien [DOM4] In-situ determination of oxygen production and respiration of an arctic hard bottom community Seidensticker and Heinrichs et al. [DOM5] Microbial degradation of natural refractory dissolved organic matter [speaker or poster presenter are emphasized]


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Fast production of diverse dissolved organic matter by a natural microbial community HELENA OSTERHOLZ1*, JUTTA NIGGEMANN1, CHRISTOPH FEENDERS2, BERND BLASIUS2, MEINHARD SIMON3, AND THORSTEN DITTMAR1 1

Max Planck Research Group for Marine Geochemistry, ICBM, Carl von Ossietzky University of Oldenburg, Germany 2 Mathmatical Modelling, ICBM, Carl von Ossietzky University of Oldenburg, Germany. 3 Biology of Geological Processes, ICBM, Carl von Ossietzky University of Oldenburg, Germany. *corresponding author: [email protected] Key words: dissolved organic matter, incubation study, FT-ICR-MS Phytoplankton production is the major source of dissolved organic matter (DOM) in the ocean. While the bulk of freshly produced (DOM) is rapidly degraded, a small part resists degradation and accumulates for thousands of years. Why DOM is stable and which abiotic and biotic processes contribute to its formation is still unknown. We hypothesize that the biotic reworking of fresh organic matter performed by microbes yields DOM similar in complexity and molecular composition to refractory DOM found in the deep ocean. We conducted a long-term incubation study, in which a phytoplankton bloom was induced by the addition of natural phytoplankton and bacterioplankton communities to DOM-free seawater. The degradation of the freshly produced DOM and the production of refractory DOM by the microbial community were followed over the course of more than 1.5 years. Three subsequent phytoplankton blooms were observed in the course of the experiment, causing dissolved organic carbon concentrations to increase up to 350 µmol L-1. By using ultra-high resolution mass spectrometry (FT-ICR-MS) we identified 10,000s of molecular formulae in DOM. First results indicate that phytoplanktonderived DOM was transformed into a DOM pool of a similar complexity as deep ocean DOM within less than 100 days, but the detected molecules are of significantly different average size and elemental composition. Thus, the biotic transformation processes do not completely explain the formation of refractory DOM, but other factors such as radiation, hydrothermal reworking and terrigenous input are likely to contribute to the composition of the deep ocean DOM.


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Origin-specific molecular markers of dissolved organic matter in the Lena Delta IVAN DUBINENKOV1*, RUTH FLERUS1,3, GERHARD KATTNER1, PHILIPPE SCHMITT-KOPPLIN2, AND BORIS P. KOCH1 1

Alfred-Wegener-Institut Helmholtz-Zentrum für Polar- und Meeresforschung, Bremerhaven, Germany 2 Helmholtz Zentrum München German Research Center for Environmental Health Research Unit Analytical BioGeoChemistry, Munich, Germany 3 present address: GEOMAR Helmholtz Centre for Ocean Research, Biological Oceanography, Kiel, Germany *corresponding author: [email protected] Key words: the Arctic, DOM, permafrost, FTICR MS The Lena River is one of the largest arctic rivers where permafrost underlies 78-93% of the watershed with continuous permafrost extending to 50°N. The amount of organic carbon accumulated in permafrost is estimated to be ~1700 Pg of carbon. The degradation and mobilization of this carbon pool would have critical implications for the carbon cycle in the Arctic and in the Lena River. Special attention has to be addressed to study DOM as the most mobile phase of organic carbon. The Lena Delta DOM samples of different origin including permafrost melt waters, ice complexes, river and its channels, lake and Buor-Khaya Bay of the Laptev Sea were analyzed by Fourier transform ion cyclotron resonance mass spectrometry (FTICR MS) and for dissolved organic carbon (DOC) and total nitrogen (TN) content. Mean DOC concentrations were 490 ± 80 µmol C*L -1 for riverine, 480 ± 60 µmol C*L-1 for bay samples and 400 ± 120 µmol C*L -1 for permafrost melt water creeks. Total nitrogen mean values were 13.7 ± 1.7 µmol N*L -1 for bay group of samples, 13.1 ± 2.8 µmol N*L-1 for the river and 19.7 ± 7.1 µmol N*L -1 for permafrost melt waters. Ice complex melt water creeks showed extremely high DOC and TN concentrations. Statistical processing (hierarchical clustering and PCA) of DOM molecular information clearly discriminated samples according to the origin. Source-dominant molecular markers were identified. We observed a continuous trend in molecular transformations of DOM during the transport from permafrost to the creek, then to the river and then to the bay. Nitrogenous components were removed from the system on the way to the Arctic Ocean, bay samples were enriched by more oxidized components. Observed trends could be interpreted as higher degradability of nitrogenous components of DOM and affection of bay processes on the DOM composition which causes increase of oxygen rich components in the bay.


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Seasonal bacteria-driven organic matter export along a tropical eutrophication gradient HAUKE F. SCHWIEDER1*, AND ASTRID GÄRDES1 1

Leibniz Institute for Tropical Marine Ecology (ZMT) GmbH, Fahrenheitstraße 6, 28359 Bremen, Germany *corresponding author: [email protected] Key words: DOM, heterotrophic bacteria, TEP, community fingerprinting, coral reefs By triggering the production of transparent exoploymer particles (TEP) by phytoplankton, bacteria can be key players in the export of organic matter to the benthos through aggregates. Although the effects of increased inorganic and organic nutrients on microbial community structures have been studied previously, their role in the bacterial contribution to particle formation, especially in coastal tropical ecosystems, remains poorly understood. We sampled along a cross-shelf gradient in the Spermonde Archipelago off Makassar, South Sulawesi, Indonesia in October 2012 (dry season) and in February 2013 (rainy season). This area offers ideal conditions to study in-situ the anthropogenic impacts on microbial communities along a well-studied cross-shelf eutrophication gradient. Chlorophyll a, as a good indicator for inorganic nutrient loading, dissolved and particulate organic matter (DOM and POM, respectively) were investigated using fluorometric and spectrophotometric techniques. Changes in the microbial community along the gradient will be analyzed using Terminal Restriction Fragment Length Polymorphism (T-RFLP) and Taq-sequencing. Water quality parameters showed elevated concentrations close to the city of Makassar and decreased along the gradient. This study, as one of the first to combine quantitative and qualitative molecular techniques, will provide a first insight into how changes in organic matter availability have important implications for the cycling of organic matter through an increased bacteria-driven export. In addition, a closer investigation of the microbial communities on the sinking particles will provide complimentary insights into the transfer of potential coral pathogens in high abundances from the water column to the benthic coral reef communities.


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Variation of DOC in surface waters of Bhitarkanika Mangroves, India SASMITA K. DAS1*, AND AL. RAMANATHAN2 1

School of Geosciences, King's Buildings, University of Edinburgh, Scotland, UK School of Environmental Sciences, Jawaharlal Nehru University, New Delhi, India corresponding author: [email protected] 2

Key words: mangroves, DOC, anthropogenic, riverine, marine Mangrove forests are highly productive coastal ecosystems restricted to the intertidal zones in the tropics. They not only function as a medium for biogeochemical exchanges but also act as net exporters of nutrients and energy to the ocean resulting in a strong physical-biogeochemical coupling which makes them an incoherently complex ecosystem. They act both as a source and a sink of organic carbon. Bhitarkanika Wildlife Sanctuary is a rich, lush green, vibrant ecosystem lying in the estuarine region of Brahmani, Dhamra and Baitarani rivers in the northeastern corner of Kendrapara District, Orissa, along the east coast of India bordering the Bay of Bengal. It is the second largest mangrove ecosystem of the country. Surface waters from 18 locations spread across the entire mangrove-estuarine complex were collected in the pre-monsoon, monsoon and post-monsoon seasons to document the spatial and seasonal variations in dissolved organic carbon (DOC). The entire study area was categorized on the basis of vegetation cover, land-use pattern, pristine conditions, water bodies as well as proximity to potential anthropogenic sites. The water samples were also analyzed for various physico-chemical parameters such as pH, EC, TDS, bicarbonates, major cations and anions. In this mangrove forest, DOC concentrations in the pristine areas were high compared to the fringe areas. Organic matter is mainly derived from riverine input of terrestrial matter and/or mangrove litter and marine organic matter. Greater variability and sometimes lack of speciﬁc trends in DOC concentrations implied extensive mixing caused by anthropogenic processes and tidal/marine influence in some of the zones in this mangrove-estuarine complex. This study emphasized that DOC can be highly variable and controlled by different processes occurring in this ecosystem.


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Empirical reconstruction of correlations and directed relations within dissolved organic matter HEIDELINDE ROEDER1*, JUTTA NIGGEMANN2, THORSTEN DITTMAR2, ULRIKE FEUDEL1, AND JAN FREUND1 1

Theoretical Physics/Complex Systems, ICBM, Carl von Ossietzky University of Oldenburg, Germany. 2 Max Planck Research Group for Marine Geochemistry, ICBM, Carl von Ossietzky University of Oldenburg, Germany *corresponding author: [email protected] Key words: dissolved organic matter, clustering, correlation, time series, Granger causality Dissolved organic matter (DOM), forming a large carbon reservoir in the global oceans, plays an important role in the Earth's carbon cycle. Mainly produced and consumed in the surface water by algae growth and microbial degradation, the major part of DOM is metabolized within minutes to hours (labile fraction). Some of the DOM compounds accumulate in deeper ocean layers, reaching cycling times ranging from months (semi-labile fraction) over decades (semi-refractory fraction) up to millennia (refractory fraction). So far, little is known about the interplay of the plethora of organic molecules and the mechanisms involved in production, transformation and degradation processes. Recently, samples of surface water were taken over a period of two years at Helgoland, a site in the southern North Sea that is under hydrographic influence of ocean currents and the outflow of the river Elbe. Here more than 9000 distinct compounds of DOM could be identified by utilization of a high resolution Fourier transform ion cyclotron mass spectrometry. Focusing on approximately 2500 hypothetical members of the semi-labile/semirefractory molecule fractions, we aggregate the high-dimensional set of time series by clustering molecules that exhibit synchronous temporal variation. To gain information about the relations between these molecule clusters, we apply and improve time series analysis techniques including linear correlation measures and linear causality measures based on Granger causality to uncover directed influences. To get a closer insight into the processes that underlie the dynamics of DOM, we also consider the influences of biological and oceanographic factors in the analysis.


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Effects of combined nitrogen on nitrogen fixation and biomass development of Baltic Sea Aphanizomenon sp. ANNA ZAKRISSON1*, ULF LARSSON1, AND HELENA HÖGLANDER1 1

Department of Ecology, Environment and Plant Sciences, Stockholm University, Frescati Backe, SE-10691, Sweden. *corresponding author: [email protected] Key words: cyanobacteria, Baltic Sea, nitrogen fixation, Aphanizomenon sp., biomass We studied effects of combined nitrogen on nitrogen fixation by using planned variations in the nitrogen discharge from a modern sewage treatment plant in Himmerfjärden Bay, northern Baltic Sea Proper. In 2007-8 nitrogen removal was discontinued to be resumed in 2009 when also the outfall was moved from 25 to 10 m depth above the seasonal pycnocline. This study was part of a large scale experiment to minimize growth stimulation of diazotrophs, mainly the ecologically dominant Aphanizomenon sp., that followed the introduction of nitrogen removal in the STP in 1997. Using stable N isotopes, we found nitrogen fixation to be virtually insensitive to combined nitrogen: The results showed that δ15N-values were similar in cyanobacteria collected at all stations along a strong gradient in nitrogen and δ15N in combined nitrogen determined from δ15N in seston (US$70million. A large part of the cultivation, however, is still conducted without legal authorization thus formal control. Multiuse of the bay, overlapping stakeholder groups, and complex political structures make interdisciplinary management efforts for the bay’s system a challenging priority. A recently initiated study will determine the bay’s ecological and economic carrying capacity in order to achieve sustainability of scallop culture in the region. Carrying capacity was defined as the maximum amount of cultivated organisms that a system can support without causing unacceptable impacts on the ecological or social level. Using different modeling approaches (e.g. ECOPATH), respective limits will be determined. Ecological experiments will provide information to establish a trophic model by investigating how the increase of scallops’ biomass due to culture efforts has changed trophic fluxes within the system. Data from ecological and socio-economic surveys will be integrated to explore the response of the system under different environmental conditions and culture scenarios. However, for a holistic and realistic approach to analyze sustainable production levels, perceptions of different stakeholder groups towards sustainability and what represents unacceptable changes in the system need to be integrated. The resulting carrying capacity thresholds are urgently needed to establish a decision-framework supporting both local fishers and managers in their difficult task of finding an ecological and socio-economic sustainable level of scallop cultivation in this region of Peru. Session II The ecosystem approach and beyond: multidisciplinary science for sustainability in fisheries

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Application of remote sensing in fisheries harvesting in the coastal waters of Tanzania, East Africa Henry Abi1* and Semba Masumbuko2 1

Marine Research Institute, University of Cape Town, Private Bag X3, Rondebosch 7701, South Africa 2 National Environment Management Council, Regent Estate Plot No. 29/30, P.O. Box 63154 Dar es Salaam, Tanzania *corresponding author: [email protected] Keywords: fish catch, potential fishing ground, migration, sea surface temperature, chlorophyll-a Satellite images provide important information on oceanographic conditions which affect the distribution and abundance of fish population. An assessment of fish catch using remote sensing was used to understand fish habitat in the Zanzibar and Mafia channels along the east coast of Tanzania in 2010. This study seeks to determine the preferred range of chlorophyll-a and Sea surface temperature (SST) for fishing and to map potential fishing grounds based on the oceanographic variables. SST and chlorophyll-a concentration derived from MODIS/Aqua images together with fisheries catch data were used to map potential fishing grounds. Calculations of monthly average of Chl-a and SST were compared with corresponding fish catch data. For the Zanzibar channel, the average of SST during the study was 27.50C, the highest average was in March and August was the lowest. The average of chlorophyll-a concentration in the Zanzibar channel was 0.53mg/m3, April was the highest and the lowest concentration of chlorophyll-a was in December. While for the Mafia channel, average SST for the year was 27.90C with the highest being in March and the lowest in August. Hence, there was correlation between Chl-a and SST for both channels with records of higher values in the Mafia channel. Based on the available catch data, the preferred range with the highest fish catch were closed to chlorophyll-a concentration of 0.56mg/m3 and SST of 28.10C for Zanzibar channel while that for Mafia channel were 1.41mg/m3 and 28.40C respectively. The largest delta brings in lots of nutrients which attract fish migration toward the Mafia channel during northeast monsoon (November – March), and moved toward the eastern part during inter monsoon. In contrast, on the southeast monsoon (May – September), fishes are spread across waters. Mapping of habitat suitability of Session II The ecosystem approach and beyond: multidisciplinary science for sustainability in fisheries

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fish populations in the Tanzania n coastal waters depend on the oceanographic factors and primary productivity.

Conservation of the endangered endemic Caspian salmon stocks in the Southern Caspian Sea Mohammad Jalil Zorriehzahra1*, Mohammad Sayad Bourani3, Sharam Abdolmaleki2, Mohamma Reza Mehrabi1, Behrouz Bahramian3, Sohrab Rezvani1, Masoud Haghighi3, Sharouz Baradaran Noeiri4 and Hajat Safikhani3 1

Iranian Fisheries Research Organization (IFRO), Hemmat highway, Paykan shahr, Sarve Azad, Ave., West 8th St., Botanical National Blvd. Tehran, Iran 2 Inland Water Aquaculture Institute, P. O. Box: 66, Ghazian, Bandar anzali, Gilan province, Iran 3 Coldwater Fishes Research Center (CFRC), Lead Center of Network of Aquaculture Centers in Asia Pacific (NACA), P. O. Box: 46815-467,18 th Km of Dohezar Road , Tonekabon, Mazandaran, Iran 4 International Sturgeon Research Institute, Sanghar, Rasht, I.R. Iran *corresponding author: [email protected] Keywords: Iran, Caspian Sea, conservation, Salmo trutta caspius The National Project is funded by the CASPECO Project which is the Third Phase of the GEF supported project in the Caspian Sea region titled “The Caspian Sea: Restoring Depleted Fisheries and Consolidation of a Permanent Regional Environmental Governance Framework” , and implemented by the Iranian Fisheries Research Organization (IFRO) in partnership with four Coastal Research Centers affiliated to IFRO, Coldwater Fishes Research Centre (CFRC).The project's objective is to improve the conservation and restoration of Caspian Salmon (Salmo trutta caspius) stocks. In accordance with IUCN criteria Caspian Salmon is placed in the red list of endangered fish. In the recent decades the destruction of habitats for juveniles, reduction of genetic diversity and fish immune system were main causes of the Caspian salmon decline. Numbers of public meetings were held with participation of fishing communities’ representatives, experts, relevant local authorities and experts of the IFRO and Iranian Fisheries Organization (IFO), Iran Environment Protection Session II The ecosystem approach and beyond: multidisciplinary science for sustainability in fisheries

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Organization (IEPO), Water Resource Management (Ministry of Energy) and University senior professors, in order to create interaction and understanding of the project objectives. Educational awareness and extension program were conducted with the involvement of fisheries communities, private sector and NGO associations. The results of the project suggests that cross-sectoral coordination for sustainable fisheries can be achieved through building partnerships and enhancing communication between the environment, private, fisheries sectors and academia. Cross-sectoral cooperation through this project improved public awareness on growing risks facing Caspian Salmon from different sources including local sources (illegal fishing and over-fishing, urban wastewater, environment destruction, industrial pollutants, pollution of air and water resources), new emerging and invasive organisms, climate change, implications of the Caspian salmon population decline on economic and social affairs of the people who depend on them for their livelihood and food security and their role in fish stock protection.

Collective Action in a Marine Social-Ecological System in Colombia By Luz Elba Torres1*, Achim Schlüter1 and Maria Claudia Lopez2 1

Leibniz Center for Tropical Marine Ecology (ZMT), Fahrenheitstr. 8, 28359 Bremen, Germany 2 Department of Community, Agriculture, Recreation and Resource Studies, Michigan State University, Michigan, East Lansing, MI 48824, United States * corresponding author: [email protected] Keywords: Social-Ecological Systems (SES) Framework, common-pool resources, collective action, Ciénaga Grande de Santa Marta, Colombia The main goal of this research is to understand why, in Tasajera, a small fishing community located in the Caribbean Coast of Colombia, collective action for a sustainable resource use of fisheries has failed. The community is made up of approximately 8,000 people that depend mainly on the fishery in the Ciénaga Grande de Santa Marta for their livelihoods, in addition to multiple sources of external aid funding. The Ciénaga is an estuarine lagoon characterized by an open access regime. It has been affected by various anthropogenic activities for several years, which have reduced its fishery resources and deteriorated the quality of life for communities that depend on it. Session II The ecosystem approach and beyond: multidisciplinary science for sustainability in fisheries

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To understand the collective action problems in this community, we used the Social-Ecological System Framework developed by Elinor Ostrom in 2007, a generic and multitier framework that enables an analysis of any form of socialecological system. The application of this framework was carried out in August of 2011 and between November of 2012 and March of 2013. The data was collected mainly through three sources: i) studies about the physical and biological aspects of this coastal lagoon; ii) formal and informal interviews conducted with 120 fishers, 15 key informants and 15 experts in different topics related to the lagoon, and finally, iii) a survey administered to 173 fishers. The results show that collective action has not taken place in Tasajera for various reasons: the community fears for their lives as a result of violent illegal groups in the area, the absence of a new generation of community leaders, the distrust of fishers in their current leaders, the lack of income alternatives, and as a result, extreme poverty, as well as a belief of some fishers that the lagoon always will have fish.

Modelling the Spatial Distribution of Herring in the North Sea Tim Dudeck1* and Jens Floeter1 1

Institute for Hydrobiology and Fisheries Science, University of Hamburg, Olbersweg 24, 22767 Hamburg, Germany *corresponding author: [email protected] Keywords: herring, North Sea, spatial distribution, regression kriging As part of the VECTORS project, a North Sea ecosystem model is going to be built and the spatial distribution of herring has not yet been implemented. Hence, it would be desirable if the distribution could be linked to simple oceanographic models, which was investigated in this study. The aim was to model the spatial distribution of North Sea herring (Clupea harengus) based on the physical habitat properties temperature, salinity and depth and thereby defining suitable habitats for herring in terms of oceanographic conditions. Based upon third quarter catch data from the International Council for the Exploration of the Seas (ICES) generalized additive models (GAMs) were used to determine which physical variables could predict herring abundances the best. To account for spatial autocorrelation a statistical technique called

Session II The ecosystem approach and beyond: multidisciplinary science for sustainability in fisheries

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Regression Kriging was used. The best-fit annual models were then taken to spatially predict herring abundances for the years 1991 to 2005. It was found that sea surface temperature in combination with a stratification proxy gave best estimates for the spatial distribution of herring. These covariates are promising candidates to parameterize herring distribution in a North Sea ecosystem model. Model predictions revealed two large scale fundamental habitats for herring: the northwest North Sea near the British coasts and the southeast. The distribution of herring in the latter was directly predictable with the models, whereas the northwest distribution displayed greater spatial autocorrelation and hence larger uncertainty. It is thus possible to define general habitats with only physical variables, but for concise ecosystem models other covariates like prey abundance are needed.

The effect of acoustic deterrent devices "pingers" on two commercially important fisheries target species in Iberian Atlantic waters Sabine Goetz1*, Begoña Santos2, José Vingada1, Damián Costas Costas3, Antonio González Villanueva3 and Graham Pierce1,4 1

Centro de Estudos do ambiente e do mar (CESAM), Universidade de Aveiro, Campus Universitário de Santiago, 3810-193 Aveiro, Portugal 2 Centro Oceanográfico de Vigo, Instituto Español de Oceanografía (IEO), Subida a Radio Faro 50, 36390 Vigo (Pontevedra), Spain 3 Estación de Ciencias Mariñas de Toralla (ECIMAT), Universidade de Vigo, Illa de Toralla s/n, 36331 Vigo, Spain 4 School of Biological Sciences, University of Aberdeen, Zoology Building, Tillydrone Avenue, Aberdeen AB24 2TZ, UK *corresponding author: [email protected] Keywords: pinger, sardine, horse mackerel, stress response, cetacean-fishery interactions Acoustic deterrent devices (pingers) that are designed to deter marine mammals from fishing gear have been successfully employed to reduce cetacean-fishery interactions. In Spanish and Portuguese net fisheries they may be applied to mitigate catch loss, gear damage and cetacean bycatch resulting Session II The ecosystem approach and beyond: multidisciplinary science for sustainability in fisheries

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from interactions with locally abundant cetacean species, such as common and bottlenose dolphins. Pinger use is, however, only feasible if negative effects of the pinger sound on the fisheries target species can be ruled out. Noise can induce short-term stress responses in fish that are reflected in increased blood cortisol concentrations and by alterations of their swimming behaviour, potentially leading to reduced catch rates. In order to test this hypothesis, the aim of our study was to assess the behavioural and physiological stress response of two shoaling pelagic fish species, European sardine and Atlantic horse mackerel, both important fisheries target species in Iberian Atlantic waters, to the sounds of three commercially available pinger models. We analysed the swimming behaviour of wild captive fish exposed to pinger sounds in tanks by means of underwater camera images and measured their blood plasma cortisol concentration. Mixed effect models were used for statistical analysis. We found that the sounds of two pinger models caused subtle changes in the swimming behaviour of both fish species and in sardine plasma cortisol concentrations. Although these alterations were statistically significant, they were very small when compared to the values reported in similar studies. We therefore believe that the variations measured in our study are more likely to be caused by biological and environmental factors rather than reflecting acute stress responses. Our results indicate that the sounds of the trialled pingers do not have a negative effect on the swimming behaviour of sardines and horse mackerels and should consequently not have any significant impact on catch rates.


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Finet: The Fisheries Research Network By Corinna Schendel1*, Giovanni Romagnoni1,2 and Sophia Kochalski1,3 1

Finet Centre for Ecological and Evolutionary Synthesis, University of Oslo, Norway 3 School of Environmental Sciences, University of Liverpool, UK 2

*corresponding author: [email protected] Keywords: young scientists, information, network, knowledge The Fisheries Research Network (Finet) is an independent, free and open network of young fisheries scientists. It is a grassroots movement that aims at connecting young people with a passion for marine and fishery science. Finet encourages the sharing of information and knowledge via blogging, workshops and online discussions. Finet collects, organises and shares information on its webpage http://finetwork. wordpress.com and provides a platform for lively communication and knowledge exchange between young fishery scientists.


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Session III Marine measurement technologies: Science and Engineering Alexandra Gottschall1 and Saskia Heckmann2* 1

Triton Submarines LLC, 9015 17th PlaceVero Beach, Florida 32966, USA

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*SubCtech GmbH, Wellseedamm 3, D-24145 Kiel, Germany

The European Union’s Water Framework Directive (WFD) requires to cover a number of ‘water quality elements’ including, physico-chemical, hydro-morphological, biological and chemical parameters around Europa. For many of these parameters measurement technology are available especially to measure bulk physic chemical parameters i.e. conductivity, dissolved oxygen, nutrients, carbon dioxide and pH. Still, accuracy could be improved or ways how to measure multiscales could be invented. To measure this parameter and realize the directive marine technology and competence are critical input factors. Further more in different kind of working areas like the offshore petroleum sector, shipping and marine research's equipment industries, and in fishing and aquaculture this knowledge is important. The aim of this session is to raise cooperation between young scientists and engineers who have brilliant ideas for design, invention and development of marine measurement technology.

Contents Talks [time slots] Frank et al. [13.9.2013; 3.30 pm] Carbonate parameters and their determination in seawater Lefering et al. [13.9.2013; 3.45 pm] Carbonate parameters and their determination in seawater Luhtala et al. [13.9.2013; 4 pm ] Connecting Secchi depth and euphotic depth in coastal waters Stephanova et al. [13.9.2013; 4.15 pm] The research of near-estuarine areas of small and medium rivers in the Black Sea

Session III Marine measurement technologies: Science and Engineering

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Posters [ID] Drinkorn et al. [III.1] Fluidic Optimization of a moored Profiler for measured Data Improvement Friedrichs et al. [III.2] Approach for long-term observation fluorescence in complex coastal waters by means of mobile phones

Carbonate parameters and their determination in seawater CARSTEN FRANK*, PEER FIETZEK1,3, AND STEFFEN AßMANN2,3 1

CONTROS Systems & Solutions GmbH, Wischhofstrasse 1-3, Bld. 2, 24148 Kiel, Germany 2

Helmholtz-Zentrum Geesthacht GmbH, Institute of Coastal Research, Max-PlanckStraße 1, 21502 Geesthacht, Germany 3

GEOMAR Helmholtz Centre for Ocean Research Kiel, Wischhofstrasse 1-3, 24148 Kiel, Germany *corresponding author: [email protected] Key words: carbonate parameters, seawater, pH, pCO2, total alkalinity The determination of carbonate parameters becomes more and more important in many seawater based research activities as well as industrial applications. On the measurement of carbon dioxide partial pressure (pCO2), seawater pH, total alkalinity (TA) and total inorganic carbon (DIC) many publications exist. These parameters can be determined by various instruments ranging from benchtop analyzers to versatile underwater sensors depending on the target analyte. For most of the parameters commercial solutions are available and the determination task is sometimes considered to be routine. While these measurements with sufficiently high accuracy are still particularly difficult in a laboratory environment where environmental conditions can be controlled to a certain degree, shipboard or in situ measurements are even more demanding. We will give an overview of common approaches for the determination of pCO2, pH as well as TA. The capabilities and limitations of respective instruments will be discussed and an outlook for future sensors and their expected properties will be given.


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Quantitative absorption determination for natural waters and associated measurement uncertainties KATHARINA LEFERING* AND DAVID MCKEE1 1

Marine Optics and Remote Sensing, Department of Physics, University of Strathclyde, 107 Rottenrow, G4 0NG, Glasgow, Scotland *corresponding author: [email protected] Key words: absorption, remote sensing, measurement uncertainties Optical properties of marine waters can provide useful information on the concentration of a variety of natural constituents, such as phytoplankton, mineral particles and colored dissolved organic materials. Ocean Colour Remote Sensing (OCRS) uses optical measurements to monitor physical and biological processes in the ocean on a global scale. However, the validation of OCRS algorithms relies on surface-based observations and significant problems occur obtaining truly quantitative data for optically complex waters such as coastal areas and shelf seas. In the past the development of accurate OCRS algorithms using radiative transfer theory has been limited by the quality of measured optical properties, such as absorption, attenuation and backscattering. For example, accurate determination of absorption coefficients is challenging because particulate components scatter a large proportion of the light and measurements have to be corrected for these effects. In recent years new measurement techniques have been developed to minimize the systematic errors that hinder existing absorption methods. In the PSICAM (Point-Source Integrating Cavity Absorption Meter) natural water samples are measured inside a calibrated integrating sphere. Therefore scattering effects are eliminated because the light field insight the sphere is totally diffuse and the PSICAM has increased sensitivity due to a long optical path length. Although the PSICAM has many advantages over common techniques, a careful assessment of the instrument and a deep understanding of its rather complex mathematics are required to achieve optimal performance and obtain robust measurement uncertainty values. A theoretical model was developed to examine which parameters most strongly influence the PSICAM calibration procedure as well as the calculation of absorption coefficients. The model shows how small measurement errors can propagate through the calibration process into large overall uncertainties. This provides a new understanding of error sources in PSICAM measurements and opens up new ways for further improvements of the instrument.


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Connecting Secchi depth and euphotic depth in coastal waters HANNA LUHTALA1* AND HARRI TOLVANEN1 1

University of Turku, Section of Geography, Department of Geography and Geology, University of Turku, 20014 Turku, Finland *corresponding author: [email protected] Key words: euphotic depth, Secchi depth, conversion coefficients, optimization, coastal waters Solar radiation in water is crucial to marine life as the energy source for photosynthesis. Thus, the underwater light field, particularly the thickness of the photosynthetically active surface water layer, is an important environmental variable to be monitored. The amount of aquatic light can be assessed by defining euphotic depth (Zeu), which refers to the depth in which 1 % of the amount of photosynthetically active radiation (PAR, 400–700 nm) measured immediately below surface remains. Another, easier and simpler way to evaluate the optical properties of water is to measure Secchi depth (Z SD), which is the depth in which a white Secchi disc disappears from sight. The ZSD method has much longer history than any of the modern optical measurement techniques. Furthermore, as a cheap and quickly executable method, ZSD measurements are still very commonly included in marine observation campaigns, even the ones not directly related to ocean optics. This extensive, and continuously increasing, Z SD data can be taken into more efficient use by converting ZSD readings into Zeu estimates. The conversion procedure has been criticised for its inaccuracy, but as it is very commonly used anyway, we aim to optimize its use. The accuracy of the procedure is based on choosing the optimal conversion coefficient, which can, especially in coastal waters, greatly vary among locations and occasions. Therefore, we compared different categorisation types of these coefficients. The in situ measured Z SD and Zeu pairs used in this study were measured in the SW-Finnish archipelago, in the Baltic Sea, which provides very varying water quality conditions within a rather small area. Temporally, the data covered an entire growing season. We found out that the conversion functions perform well, but they require local calibrations. If calibration with true PAR data is unfeasible the ZSD based coefficients seem to work best.


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The research of near-estuarine areas of small and medium rivers in the Black Sea SVETLANA STEPANOVA1*, ALEXANDER POLUKHIN1 AND ALEXANDER POPOV1 1

Shirshov Institute of Oceanology RAS, Nakhimovsky Avenue 36, 117997 Moscow, Russian Federation *corresponding author: [email protected] Key words: near-estuarine areas, small rivers, the Black Sea coastal zone Thus far, the emphasis in the study of river flow effects on coastal ecosystems of the Black Sea was focused on estuarine areas of major rivers such as the Danube, the Dnieper etc. Small and medium rivers haven’t been studied sufficiently, that was mostly due to methodical problems, in particular, because of inconsistency of observation discreteness with the scale of investigated natural objects. The study of inhomogeneities with this scale requires a completely different approach. Application of standard oceanographic techniques based on a grid of hydrological stations is ineffective by reason of small size of studied objects. Since 2006, coastal expeditions aimed on the study of near-estuarine areas of small and medium rivers in the Russian sector of the Black Sea have been annually made by workers of SIO RAS. One of the tasks of this work is development of research methods of meso- and submesoscale hydrophysical and hydrochemical inhomogeneities in near-estuarine areas structure. The focus was on efficient data delivery and measurements discreteness selection suitable to the study of hydrochemical and hydrophysical fields variabilities of small scales. As a result, the scheme of work that include continuous registration of hydrophysical, hydrochemical, hydrobiological and biooptical parameters on course of a vessel and stationary measurements of meteorological parameters and currents velocity in rivers estuaries during the whole work period was created. Sampling for subsequent determination of nutrients, chlorophyll «a» and other parameters and vertical profiling of hydrophysical parameters were carried out in key points (in the areas where strong variations or registered values extremums were observed), not on a pre-planned grid. This technique allows to advance a new level of processes research in the Russian sector of the Black Sea coastal zone, and also shows the character of distribution and transformation of pollutants bringing with continental runoff.


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Fluidic Optimization of a moored Profiler for measured Data Improvement CATHERINE DRINKORN1*, RALF PRIEN1 1

Leibniz Institute for Baltic Sea Research Warnemünde, Seestr. 15, 18119 Rostock, Germany *corresponding author: [email protected] Key words: moored profiler, fluidic shaping, measurement resolution High-resolution measurements in space and time of a wide range of parameters within the water column are of increasing importance in terms of detecting changes of the marine ecosystem on different time scales. Profiling moorings are becoming a tool of choice for many applications, allowing to get high resolution vertical profiles at a single location with time resolution of hours to days (depending on deployment period) without the need for a ship to remain in the investigation area. With changing currents impacting on the profiler movement and measurements an optimized shape of the profiling body is needed to maintain data quality. This presentation will show the design process for a profiling instrumentation platform (PIP) operated with an underwater winch. Different designs were considered and selection criteria for the chosen design will be discussed. The performance of the optimized shape body (PIP3) will be compared to the simpler shaped one (PIP2) currently used in the Gotland Basin of the Baltic Sea, employing fluidic analysis and jet stream canal tests. Motion data from the current profiling body PIP2 will be shown and expected improvements for the PIP3 presented.

Approach for long-term observation fluorescence in Session III Marine measurement technologies: Science and Engineering

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complex coastal waters by means of mobile phones A. Friedrichs1*, J. A. Busch1, AND O. Zielinski1 1

ICBM, Emsstraße 20, 26382 Wilhelmshaven, Germany

*corresponding author: [email protected] Key words: IOPs, fluorescence, coastal waters, smart phone, Citclops The marine environment in particular the complex coastal waters like the Wadden Sea are multifaceted. It is exposed to persistent alteration, fluctuation and anthropogenic and nonanthropogenic pressure on resources. Thus a balanced interaction between the single stress factors is of great importance for an efficient ecosystem. Therefore, it is required to observe the state and the change of the fragile ecosystem by measuring optical properties. Important indicators for changes are different parameters such as chlorophyll a (Chl a) as proxy for algal biomass, suspended matter, and coloured dissolved organic matter (CDOM). Particularly in the coastal zone with high concentration of a mixture of substances it is a challenge to discriminate the different key parameters based on their inherent optical properties (IOPs) like fluorescence. Also a large-scale and long-term observation is problematic. Up to now, long-term measurements are usually recorded at fixed measurement stations or are taken by research vessels or ships of opportunity along transects, and an enhancement of the spatio-temporal coverage of such measurements by means of IOPs is highly desirable. One approach is the integration of citizens into the data acquisition process. To achieve this goal we approach the measurement of key parameters of Wadden Sea processes by means of fluorescence with smart phones within the EU-project Citclops (Citizen's observatory for coast and ocean optical monitoring). This will enable the inclusion of citizens to Wadden Sea surveillance and thereby an increased spatio-temporal coverage of observations. The first step for this mission is checking the applicability of internal smartphone elements, such as the integrated flash light for the induction, and the camera for detection of fluorescence.


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Session IV Marine Plastic Pollution: From sources to solutions SVENJA BEILFUß1* and JOHANNA WIEDLING2 1

*BIOCONSULT Schuchardt & Scholle GbR, Reeder-Bischoff-Straße 54, 28757 Bremen, Germany 2

Leibniz Center for Tropical Marine Ecology (ZMT) GmbH, Fahrenheitsr. 6, 28359 Bremen, Germany Plastic accounts for around 70% of the marine debris and since synthetic material has a long decomposition time it poses a great risk for the marine environment. Physical, chemical and biological degradation lead to smaller plastic particles. These microplastics also accumulate in the marine environment bringing about yet unknown threads. Plastic pollution is a complex subject causing tremendous ecological, economical and social problems. Young researchers are invited to contribute with their work on plastic in the marine environment and its associated problems to solve the gaps in our knowledge. We would also like to encourage the presentation of management recommendations and strategies on how to reduce and monitor marine plastic pollution.

Contents Talks [time slot] Werner [13.9.2013; 8.30 am] INVITED SPEAKER Neumann et al. [13.9.2013; 8.45 am] Evaluation of marine litter transport simulations in the German Bight from monitoring perspective Löder and Gerdts [13.9.2013; 9.00 am] FT-IR analysis for monitoring marine microplastics Mildenberger et al. [13.9.2013; 9.15 am] Fouling and Degradation of Plastic in the Marine Environment Nerheim et al. [13.9.2013; 9.30 am] Diversity and Abundance of Plastic-Associated Marine Microorganisms Haemer et al. [13.9.2013; 9.45 am] Uptake, Transport and Deposition of Microplastics in Marine Isopods

Session IV Marine Plastic Pollution: From Sources to Solutions

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Evaluation of marine litter transport simulations in the German Bight from monitoring perspective DANIEL NEUMANN1*, ULRICH CALLIES1, MICHAEL MATTHIES2, Marcus Schulz2 1

Institute of Coastal Research, Helmholtz-Zentrum Geesthacht, Max-Planck-Str. 1, 21502 Geesthacht, Germany 2

Institute of Environmental Systems Research, University of Osnabrück, Barbarastr. 12, 49076 Osnabrück, Germany *corresponding author: [email protected] Key words: marine debris, Lagrangian transport modeling, wind drift, intra-annual variation, source-receptor relationship Ensemble drift simulations were performed with an offline Lagrangian transport model. Passive tracers, partly affected by additional wind drift, represented submerged and atop floating marine litter items. Over 9 years every 28 hours particles were injected in the German Bight and drifted 90 days forward and backward in time. Forward simulations were evaluated with respect to real coastal monitoring sites. Modeled time series of litter abundance at Sylt clearly show seasonal variations with maxima in autumn. This is caused by varying distance of coast-parallel currents to the coast of Schleswig-Holstein. Single backward simulations show a wide spectrum of possible source regions. However, temporally averaged backward simulations started from East Frisian Islands suggest primarily westerly located source regions. Particles started from the North Frisian Islands originated from the Elbe estuary or also from the west. In forward and backward simulations, additional wind has a considerable influence on the particle drift: Particle abundance and residence times at coasts are increased. At the same time residence times at the open sea decrease considerably. In time series of wind drifted items, seasonal patterns are less developed than in those of not wind drifted ones and noise is higher. Results clearly show that seasonal variability in beach litter monitoring data partly results from natural variability in ocean currents and winds. Combining litter monitoring data with backward simulations seems reasonable. The parameterization of the vertical position of litter items in the water column by scaling the wind drift is uncertain and adds considerable uncertainty to model results.


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FT-IR analysis for monitoring marine microplastics MARTIN G. J. LÖDER1* AND GUNNAR GERDTS1 1

Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, Biologische Anstalt Helgoland, Kurpromenade 201, 27498 Helgoland *corresponding author: [email protected] Key words: FT-IR spectroscopy, marine microplastics, monitoring Persistent plastics are hardly degraded and accumulate in the marine environment. Their fragmentation leads to an increasing amount of small plastic particles, so-called microplastics. Due to their size, these have the potential of entering marine food webs. For a reliable evaluation and an assessment of food web effects, a detailed quantitative and qualitative monitoring of microplastics in the marine environment is highly required and thus stipulated within the framework of the Marine Strategy Framework Directive (MSFD). Due to the sampling procedures and the sample analyses currently used, the scarce data on microplastics concentrations are mostly biased towards larger particles. Therefore, reliable data on concentrations of the total size spectrum of microplastics in marine systems and especially in German coastal waters are still lacking. Furthermore, the polymer origin of potential microplastic particles needs to be verified during analysis. Fourier Transform infrared (FT-IR) spectroscopy offers the possibility of proper identification of plastic particles in environmental samples. However, standard FT-IR spectroscopy still requires time- and labour-consuming pre-sorting of particles by hand. Hence, small or less abundant microplastics are potentially overlooked. A highly promising FT-IR extension (FT-IR Imaging) allows for detailed and unbiased high throughput analysis of total microplastics in a given sample without prior pre-sorting by hand. Thus the project MICROPLAST aims on (1) the development/optimisation of appropriate methods for the extraction of microplastic particles from complex matrices (e.g. sediment, plankton, tissue), (2) the evaluation of FT-IR imaging for the analysis of microplastics and the development of procedures for its routine application, (3) the first-time production of valid data on the pollution of the pelagic and benthic zone with microplastic particles in German coastal waters.


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Fouling and Degradation of Plastic in the Marine Environment TOBIAS MILDENBERGER1, ANDREAS EICH2, JOHANNA WIEDLING3, CHRISTIAN LAFORSCH1 AND MIRIAM WEBER*,4,5 1

University of Bayreuth, Universitätsstraße 30, 95447 Bayreuth, Germany

2

University of Bremen, Bibliothekstraße 1, 28359 Bremen, Germany

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Leibniz Centre for Marine Tropical Ecology, Fahrenheitsstraße 6, 28359 Bremen, Germany 4

Max Planck Institute for Marine Microbiology, Celsiusstraße 1, 28359 Bremen, Germany

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HYDRA Institute Field Station Centro Marino Elba, Via del Forno 80, Fetovaia, I-57034 Campo nell’Elba (LI), Italy *corresponding author: [email protected] Key words: biodegradable plastic, marine pollution, biofouling, biodegradation Increasing amounts of plastic accumulate in the oceans and harmful consequences for marine ecosystems have already been shown. Hence, knowledge on biodegradation in marine environments is a prerequisite to foster management strategies in the future. Since plastic debris serves as substrate for microorganisms, this biofilm may result in biodegradation of the polymer. However, little is known about the composition of these biofilms and how it affects the degradation of plastic. This pilot-study aimed investigating microbial biofouling of biodegradable and conventional plastic bags. We exposed conventional and biodegradable plastic to the Mediterranean Sea in the Bay of Fetovaia, Elba, Italy. Additionally a mesocosm experiment with controlled parameters was performed. We investigated the microbial settlement in the first 5 weeks after plastic bag pieces had reached the ocean. Therefore the amount of biofilm and diatoms (including classification) were measured. The total microbial activity was determined measuring oxygen consumption/production rates and oxygen profiles throughout the biofilm. For estimating degradation, tensile properties were investigated. The tensile strength of both plastic types declined indicating biodegradation in our experiments. No differences could be observed between both plastic types. The settlement of microorganisms on the plastic surface increased with time on both plastic types. We assume that the growing biofilm changes the microenvironment on the plastic surface compared to the surrounding water and thereby its degradation. The net consumption of oxygen driven by microorganisms was higher than the oxygen production. This indicates that the degradation takes place under anoxic conditions. A better understanding of plastic degradation in the marine environment will help solving the global problem of plastic in the oceans. Results clearly show that seasonal variability in beach litter monitoring data partly results from natural variability in ocean currents and winds. Combining litter monitoring data with backward simulations seems reasonable. The parameterization of the vertical position of litter items in the water column by scaling the wind drift is uncertain and adds considerable uncertainty to model results. Session IV Marine Plastic Pollution: From Sources to Solutions

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Diversity and Abundance of Plastic-Associated Marine Microorganisms MAGNUS S. NERHEIM1,2* with HENRY S. CARSON1, KATHERINE CARROLL1, MARCUS ERIKSEN3 and with GUNNAR BRATBAK2, SANDRA I. SCHÖTTNER2 1

Marine Science Department, University of Hawai ʻi at Hilo, Hilo, Hawai ʻi USA

2

Department of Biology, University of Bergen, Bergen, Norway

3

Five Gyres Institute, Los Angeles, California USA

*Corresponding author: [email protected] Key words: Marine debris, Plastic, Microorganisms, Bacteria, Diatoms Several key-processes regarding the fate and impact of plastic pollution in the ocean are likely mediated by microorganisms, including degradation, buoyancy, chemical adsorption, and colonization or ingestion by larger organisms. In a study on marine debris from the North Pacific Gyre, we related the abundance and diversity of plastic-associated microorganisms to a variety of physical and biological factors, including location, temperature, salinity, plankton abundance, plastic concentration, item size, surface roughness, and polymer type. Plastic fragments and pellets ( 265 Mt whereof an estimated amount of 10% ends up in our oceans as “marine litter”. Harmful effects of plastics have been documented for more than 267 marine animal species. Particularly birds, mammals and reptiles die after ingestion of plastic fragments or entanglement in plastic ropes. Smaller particles of less than 5 mm originating e.g. from fragmentation or hygienic products are denoted as microplastics. These particles can be ingested by a wide range of organism and thus, are recognized as a severe environmental problem. In order to estimate possible effects of microplastics on aquatic crustaceans we studied the uptake of fluorescent microplastic fibres, fragments and beads and the transport and deposition of the particles in the digestive tract of the marine isopod Idotea emarginata. Microplastics were offered in agar-based algal food to the animals. In choicefeeding assays I. emarginata non-selectively ingested food pieces supplemented with microplastics. Ingested microplastics were traced through the intestines using histological methods. Fluorescent particles occurred in high numbers in the stomach and in the gut while the tubules of the midgut gland were void of microplastics. Apparently, the unique anatomy of the stomach with the fine-meshed proventricular filter press efficiently prevents the passage of microplastics into the midgut glands. Effects of long-term exposure to ingested microplastics on the isopod fitness were assessed in biotests. Microscopic fibres and fragments had minor effects on the size increment, moult cycle and ingestion rates of I. emarginata. However, our results indicate that daily doses of 10 µm microbeads prolonged the intermoult period. Additionally, the isopods had lower ingestion rates for food containing microbeads.


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Session VI Aquaculture: Fish feeds the world – but how? Kathrin Steinberg1 and Fabian J. Schäfer2 1

Deutsche Gesellschaft für international Zusammenarbeit (GIZ) GmbH, Dag Hammarskjöld-Weg 1-5, 65760 Eschborn 2

Leibniz Institute of Freshwater Ecology and Inland FIsheries (IGB) Müggelseedamm 310, 12587 Berlin Aquaculture is more and more replacing capture fisheries in respect to the supply of seafood. However, the outstanding fast growth of this sector is facing fundamental challenges regarding sustainability, in terms of fish nutrition, possible threats to the environment, like antibiotics and other additives, as well as the unequally distributed worldwide production and resources. Large amounts of farmed seafood are produced in developing countries for export, creating a severe competition for the supply of the local population with animal protein. Only a broad holistic approach will be able to solve the mutual challenges in order to ensure a sustainable and profitable production of seafood. These aims need to include a convergence between the sustainable but often insufficiently managed backyard farms and technically evolved, but often unsustainable large-scaled production systems. Young researchers are invited to contribute their thoughts on these topics and present ideas on how and if aquaculture could be used to feed the world. We would also like to encourage the presentation of improved aquaculture practices and new ideas for both, the industrial and the traditional production.

Session VI Aquaculture: Fish feeds the world – but how?

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Contents Talks [time slot] Seemann and Lorkowski [13.9.2013; 1.45 pm] Growth & feed composition of noble crayfish – A comparison of RAS to pond systems Barman et al. [13.9.2013; 2 pm] Golden Trevally (Gnatanodon speciosus, Forsskall), A candidate species for sustainable mariculture diversification Lugert et al. [13.9.2013; 2.15 pm] Analysing the growth of turbot using nonlinear growth models Hörterer et al. [13.9.2013; 2.30 pm] Digestive enzyme profiles of juvenile turbot raised in aquaculture Akbarzade et al. [13.9.2013; 2.45] Triploid production with hybridization between female stellate sturgeon and male Persian sturgeon Khazaali et al. [13.9.2013; 3 pm] Effect of steroidal and nonsteroidal on blood sex steroids in Epinephelus coioides Poster [ID] Noveiri et al. [V.1] Relationship between flagellum length and fertilization in Persian Sturgeon (Acipenser persicus) spermatozoa Zorriehzahra et al. [V.2] Study on relation of environmental factors and health management with occurrence of Redmouth Disease in Rainbow trout Lorkowski and Seemann [V.3] Noble Crayfish in RAS – Development of a Backwash-system fort he use of natural substrate


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Growth & feed composition of noble crayfish – A comparison of RAS to pond systems Uli B. Seemann*, Kai Lorkowski Institute for Marine Resources GmbH, Bussestr. 27, 27570 Bremerhaven, Germany *corresponding author: [email protected] Key words: Noble Crayfish, Astacus astacus, nutrient supply, feed composition, Recirculating Aquaculture System Within the first study we determined the growth rate of 1-year old noble crayfish (Astacus astacus) in a recirculating aquaculture system (RAS) compared to individuals reared in an open pond farm. In the following study the lipid and energy content as well as the specific fatty acid profiles of crayfish, animal feeds and additional feed components were analyzed to optimize feeds and enhance growth rates of crayfish cultured in RAS technology. Feed including additives of mussel(Mytilus edulis) and waterweed- (Elodea sp.) meal were considered for enhancement of protein and plant amount. The results help to identify the ability of a crayfish reared in RAS and give conclusions for a new food composition for this species. 1st case study: using a commercial carp food for RAS crayfish with different rates of the average body weight, growth increase was measured by weight and carapax length. Pond crayfish with natural nutrient supply were measured and compared with RAS crayfish showing significantly better growth under outdoor conditions and therefore indicating a better nutrient supply. 2nd case study: lipids were extracted and weighed, the energy content of the food and additives was determined by calorimetric analysis and fatty acid profiles were done with gas chromatography and assigned to the specific fatty acid by FAMEMIX standard Supelco 37 (Sigma Aldrich). As assumed, animals in ponds showed different fatty acid profile and higher lipid contents and compositions compared to indoor raised crayfish, suggesting that the used commercial feed contained a lower lipid content. Results of the considered and analyzed feed component showed that M. edulis flour and dried Elodea sp. lack in essential fatty acids considered individually, but would complement each other and so could be used together as a new feed or as enhancer for the industrial fishfeed. Furthermore, an industrial feed which lacks in essential fatty acids would be balanced by Elodea sp. and M. edulis.


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Golden Trevally (Gnathanodon speciosus, Forsskall), a Candidate Species for Sustainable Mariculture Diversification Debtanu Barman1*, Tony Setiadharma2, Nyoman Adiasmara Giri2 *1Center for Aquaculture Research & Development (CARD), St. Xavier’s Vocational Training Center, Don Bosco, Bishramganj-799103, Tripura, India 2

Research Institute for Mariculture (RIM), Gondol, Bali, Indonesia

*Corresponding author: [email protected] Key words: Golden Trevally, Breeding performance, Feed types, Survival percentage. Gnathanodon speciosus is new candidate species in mariculture diversification in South-East Asia. An attempt was made to domesticate and breed this bentho-pelagic species under captive conditions to develop viable cost effective hatchery technology of Gnathanodon speciosus, golden trevally in hatchery conditions.This fish species has also been marketed as ornamental fish in international market because of its golden-yellowish color with vertical black stripes on their body. In the present work, wild golden trevally brooders were collected from the sea and tried to domesticate them in artificial cistern tank with optimum water quality conditions. Spawners (0.5-2.5 kg) released on an average 2 million eggs/day. Sex ratio was maintained 1 male: 3-4 female in the round-concrete tank (30-50 m 3) with partial water exchange everyday. Hatching occurs within 18-20 h. Feeding rate was maintained at 3-5% of the total biomass. For good maturation, vitamin mix 5-10 g /kg feed was added in trash fish and squid. As a larval food Nanochlorpsis, Rotifers, Artemia nauplii, Mysid and artificial feeds were given. Nanochlorpsis and Rotifers were given on days 1-15 days. Artemia nauplii were given 8-20 days and then artificial feeds were given up to 35 days. Juveniles were harvested on day 35 th with size of 3-4cm. Water exchange in larval tank started from day 10 with 20% exchange rate of the total volume and gradually increased up to 50-80%. Optimum larval stocking density was maintained at 10-30 no/L. D-20 larvae stage was more critical period in larval rearing. Survival rate was recorded 10-20% in the whole larval cycle period. The results of the present study would felicitate mass scale production technology of golden trevally using low cost production system and embryonic study will help to understand the feeding patterns of larvae to get maximum survival percentage in captive condition.


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Analysing the growth of turbot using nonlinear growth models Vincent Lugert1*, Georg Thaller1 , Jens Tetens1, Carsten Schulz1,2 and Joachim Krieter1 1

Institute of Animal breeding and Husbandry, Christian-Albrechts-Universität zu Kiel, Olshausenstraße 40, D-24098 Kiel, Germany 2 GMA – Gesellschaft für Marine Aquakultur mbH, Hafentörn 3, 25761 Büsum *corresponding author: [email protected] Key words: Growth, aquaculture, growth model, von Bertalanffy, Turbot Modern aquaculture recirculation systems (RAS) are a necessary tool to provide sustainable and simultaneous aquacultural production. The growth of the reared organism is the major aspect in terms of productivity. Growth, when reported in scientific or fisheries consensus, is typically displayed as absolute (gain / day), relative (% increase in body size) or specific growth rate (% increase in body size / day), computed on the basis of initial and final data and do not consider growth during this period. We analyzed the growth data of 150 female turbot reared over a period of 340 days using the three mentioned established and most commonly used growth rates (absolute, relative, specific) and three nonlinear models (Logistic, Gompertz, von Bertalanffy). Goodness of fit of each function is expressed as mean percent deviation (MPD). Nonlinear growth models are also compared by their residual standard deviation (RESSD). All growth models achieved much better goodness of fit providing lower residual standard deviation and lower mean percent deviation. Within the models, the von Bertalanffy growth function provided the best fit to the data in terms of MPD and REESD. Our results clarify that, although being widely accepted as standard, specific,- and absolute growth rate are mathematically less accurate then nonlinear growth models, especially when a precise characterization of growth of a species is required. Nonlinear growth models are a beneficial tool to describe the entire growth process of reared fish species and can be used for prediction of growth, early breeding-stock selection and production management.


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Digestive enzyme profiles of juvenile turbot raised in aquaculture Christina Hörterer1, 2*, Jan Schmidt1 and Reinhard Saborowski2 1

IMARE Institute for Marine Resources, Bussestraße 27-29, 27570 Bremerhaven, Germany 2 Alfred Wegener Institute, Am Handelshafen 12, 27570 Bremerhaven, Germany *corresponding author: [email protected] Key words: Scophthalmus maximus, probiotica, prebiotica, feed supplements, enzymes The aquaculture production of fish is growing continuously. In order to increase sustainability it is very important to optimize the production process, especially the assimilation and conversion of feeds. In this work we investigated the role of digestive enzymes in feed utilization and feed formulation of aquaculture raised turbot, Scophthalmus maximus. Colorimetric and fluorometric substrates were used to assay enzymes performing the digestion of the major feed ingredients proteins, lipids and carbohydrates. Moreover, the juvenile turbots were fed with five different pro- and prebiotic supplements and we determined the effects of the different feeds and the enzyme profiles. The turbots showed high specific growth rates and low feed conversion ratios. The total proteolytic activity in the stomach was by 80% due to acid proteinases and by 20% to alkaline proteinases. In contrast, the total proteolytic activity in the gut was mainly contributed by alkaline proteinases (94%). The activities of the endopeptidases trypsin and elastase were low. In contrast the expopeptidases showed higher activities than the endopeptidases. Esterase activities, which hydrolyzes short chained fatty acids were much higher than lipase activities. Turbots possess high chitobiase activity which enables them to digest chitin. Amylase activity was low, which indicates that turbots are not efficient in utilizing alimentary starch supplement. The different feed formulations had no significant effects on the enzyme profiles. In conclusion turbots are very efficient in converting their food. They have a high potential to utilizate proteins and short chained fatty acids. The presence of chitinolytic enzymes seems to allow using chitinous feed supplements such as e.g. the remains from shrimp peeling processes.


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Triploid production with hybridization between female stellate sturgeon and male Persian sturgeon Sajjad Akbarzade1*, Mohammad Pourkazemi, Mohammad Hassanzadeh Saber ² 1

Islamic Azad University Azadshahr Iran ²Gen Bank Center of International Sturgeon Research Institute (Rasht-Iran) *Corresponding author [email protected] Keywords: Hybridization, Microsatellite markers, Stellate Sturgeon, Persian Sturgeon Artificial hybridization was carried out between two economical species (female stellate sturgeon and male Persian sturgeon) with the aim of heritability manner of hibrid genome. For this purpose, eggs of rearing stellate sturgeon and sperm of rearing Persian sturgeon were used from Propagation and Cultivation Site of International Sturgeon Research Institute (Rasht-Iran). Then, sperm and eggs were fertilized. Fertilization rate was 97% and hatching rate was 78 percent. Also, AFUG 63 and LS 68 microsatellite markers have verified F1 progenies. These markers present that F1 has inherited two loci of paternal breeder and one locus of maternal breeder. So, there is possibility of triploidization in the hybrid progenies.

Effect of steroidal and nonsteroidal on blood sex steroids in the Epinephelus coioides Aida Khazaali1*, M.R. Ahmadi2, U.S. Sethi3 1

Young Researchers Club, Islamic Azad University, Bandar Abbas Branch, Bandar Abbas, Iran. P.O.Box:79159-1311 2 Department of Health and aquatic Diseases, Faculty of Veterinary medicin, University of Tehran, P.O.BOX:14155-6453 3 Central marine fisheries research Kochi, India (CMFRI) *corresponding author: [email protected] Key words: steroidal, nonsteroidal aromatase inhibitor, blood sex steroids, Epinephelus coioides In this study the effect of letrozole, a nonsteroid aromatase inhibitor in combination with steroid hormones methyltestosterone (as compared 0.5 to 1 mg/kg/BW) on sex inversion in protogynous orange-spotted grouper, Epinephelus coioides, was investigated. Sex change in order to make a total of 6 fish (control and treated with hormone therapy) were considered. The trial in the spring of 2012 on Session VI Aquaculture: Fish feeds the world – but how?

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Central Aquaculture Development Kolahi (Hormozgan,Iran) took place. And in three times 0, 15 and 30 to measured blood sex steroids (17β-estradiol (E2), testosterone (T) and 11- Ketotestosterone (11KT), 17α-20β-dehidroxy-4pregnan-3-one (17α, 20β,DP), Progesterone (P)).as gonadal tissue for histological studies using catheter through the vagina gonadal tissue samples were obtained. The results showed that aromatase inhibitors work well in combination with sex steroid hormones are sex changing. Also a significant increase in the levels of sex steroids T and 11KT in the treatment by Capsule after 30 days. Also, we found that a plasma level of Progesterone was not different among treated groups.

Relationship between flagellum length and fertilization ability in Persian Sturgeon (Acipenser persicus) spermatozoa Shahrouz Baradaran Noveiri Researcher, International Sturgeon Research Institute Present Address: Rasht, Iran, P.O.Box:41635-3464 *corresponding author: [email protected] Key words: sperm motility, flagellum length, Persian sturgeon, Caspian Sea Study on sperm morphology of different sturgeon species have been showed that they consisted of three major parts as head, midpiece and flagellum. The role of flagellum is very important to generate the force needed for motility .Total length of flagellum reported as 46.57-58.25 µm in Acipenser persicus spermatozoa. Sperm samples from Persian sturgeon were collected from 16 males (14.74 ± 7.45 kg weight and 151.1 ± 13.2 cm total length). Sperm morphometric characteristics were determined afterward .To avoid of the effect of density on fertilization rate, samples were chosen at a close similar spermatozoa density (mean 1.7 × 10 9/ml). Each collected sample was used to fertilize fresh eggs (10 ml/kg) and fertilization rates were recorded separately. The mean flagellar length of brood spermatozoa (n=16) was 53.82 ± 2.6 μm (range: 48.51-59.2 μm) and there was a significant difference between males (P < 0.05). Comparison of fertilization rates of these samples (67-95 %) also showed significant difference between males (P < 0.05). Data showed samples with longer flagellum length had greater fertilization rates. A.persicus spermatozoa have two lateral fins along the flagellum so it helps to generate more force for progressive movement. Because of producing more force by longer flagellum, shortening of Persian sturgeon spermatozoa flagellum length up to 11 µm could make fewer motility and result lower fertilization rates in fertilization trial of Persian sturgeon. Theoretically, longer flagellum generates greater force and faster swimming speed. It has been shown that the spermatozoa of bluegill (Lepomis macrochirus) with flagellum length slightly more than the others (>2 µm) have faster initial swimming speeds up to 40 µm/s. Although the weak relationship between sperm Session VI Aquaculture: Fish feeds the world – but how?

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flagellar length and fertilization rate could be related to quality of eggs from different females, this study showed the importance of spermatozoa flagellar length studies to evaluate fertilization capacity of Persian sturgeon.

Study on relation of environmental factors and health management with occurrence of Redmouth Disease in Rainbow trout Mohammad Jalil Zorriehzahra1*, Nima Behboudi2, Shapour Kakoolaki1, Daryoush Azadikhah2, Abbas Ali Motallebi1, Ali Nekouifar3 and Mehrdad Amirikar2 1

Iranian Fisheries Research Organization (IFRO), Hemmat highway, Paykan shahr, Sarve Azad, Ave., West 8th St., Botanical National Blvd. Tehran, Iran, 2 Islamic Azad University, Branch Uremia, Iran 3 Artemia References Research Center, Uremia, Iran *corresponding author: [email protected] Key Words: Iran, Redmouth Disease, Rainbow trout, Oncorhynchus mykiss Enteric Redmouth Disease (ERM) has been reported as second important infectious bacterial disease in Coldwater fish industry according to recent official records of Iranian Veterinary Organization in Iran. Up to now, about 15 provinces were reported as infected area and we succeed to isolated and characterized (ERM) as first record in West Azerbaijan province. Two objectives of this study were: 1) Evaluation of health status and relation between environmental factors and health management with occurrence of Enteric Redmouth Disease (ERM) in Rainbow trout (Oncorhynchus mykiss) cultured in West Azerbaijan province and 2) Epidemiological survey on occurrence of Enteric Redmouth Disease in Rainbow trout (Oncorhynchus mykiss) coldwater fish farms in region. So during Feb. 2011 to Sept. 2012, Physiochemical characteristics of water, health status and health management were evaluated and statistical calculations were done as well. Also, questionnaire survey, sampling procedure and laboratory operations for diagnostic aspects were done in 19 coldwater fish farms in region. According to our findings, some significant correlation were observed between NO3, NO2, NH3, DO, pH, water temperature and occurrence of ERD in mentioned farms. In this regard, NO2 had very important role as susceptible factor for occurrence of Yersiniosis in examined fish farms (r= 870, p=0.03).Regarding to our findings and statistical calculations, it was concluded that farms with better physiochemical characteristics and suitable health management were less likely to develop the ERM disease. Also economical lost of fish mortality had significant corolation with environmental factors and health management in examined fish farms in related provience.


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Noble Crayfish in RAS – Development of a Backwash-system for the use of natural substrate Kai Lorkowski *1, Uli B. Seemann1, 1

Institute for Marine Resources GmbH, Bussestr. 27, 27570 Bremerhaven, Germany *corresponding author: [email protected] Key words: Noble crayfish, Astacus astacus, pond design, RAS, backwash system As a benthic organism the noble crayfish (Astacus astacus) has specific requirements to the design of a recirculation aquaculture system (RAS). These are multiple hiding places and a structured habitat. In this work a recirculating aquaculture system was designed and evaluated containing coarse gravel as natural substrate. A backwash-system was installed to avoid anaerobe areas. Nine Tanks were stocked with ten one year old crayfish corresponding to a stocking density of 28 individuals per m². The crayfish were fed using a pelleted, sinkable carp food. The reduction and oxygenation potential ORP were measured in the pore water to identify anaerobe areas. After four weeks the gravel had been backwashed once a day for additional two weeks. Coarse gravel was an excellent substrate for the wellbeing of noble crayfish showed in no morality and no extremity losses over eleven weeks. But over the time increasing anaerobic areas occurred all over the tank bottom with denitrifying processes. The backwash-system was insufficient to avoid these anaerobic areas, but showed a trend in reducing the denitrifying processes leading to rising nitrate levels in the process water. As a recommendation the design has to be improved and a system should be developed to avoid anaerobic areas better but to keep the coarse gravel as substrate.


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Session VI Marine Habitat Mapping: stretching the blue marble on a map RUGGERO MARIA CAPPERUCCI Senckenberg am Meer, Department of Marine Science , Südstrand 40, D‐26382 Wilhelmshaven phone: +49 (0) 4421 9475 212 email: [email protected] Marine Habitat Mapping can be described as a process to simplify the marine environment in a discrete amount of parameters. It is a key tool for environmental analysis, policy making and future development planning. It gathers expertise from a wide range of disciplines, e.g.: geosciences, engineering, biology, physics, ecology, and modeling. The increasing demand for versatile uses of marine environments makes the outcomes even more relevant for legal and socio-economic applications. The integration of multiple remote-sensing techniques (acoustics, aerial and satellite images) coupled with punctual ground-truthing (sediment and/or biological samples, video/photo analysis) and with statistical/GIS analysis is becoming a standard tool. The session will welcome contributions about: Marine habitat mapping techniques, Coastal and deep-sea habitat mapping: case studies, Human disturbance and habitat changes

Content Talks [time slots] Jung R. et al. [13.9.2013; 8.35 am] High Resolution Remote Sensing Images for Tidal Lands Change Detection Singer A. et al. [13.9.2013; 8.50 am] Modelling the distribution of benthic species in the Jade Bay in response to environmental change Biondo M. and Bartholomä A. [13.9.2013; 9.05 am] Long-term interactions of large scale hydrodynamics, human impacts and sedimentary processes – an integrated multi-technique study. Ingrassia M. et al. [13.9.2013; 9.20 am] Session VI Marine Habitat Mapping: stretching the blue marble on a map

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Gas related features offshore the western pontine islands (Tyrrhenian Sea) Nowell M. S. et al. [13.9.2013; 9.35] Composition, configuration or complexity: spatial metrics to manage disturbed seascapes Poster [ID] Ritzmann A. [VI.1] Jade Bay surface sediment analysis

High Resolution Remote Sensing Images for Tidal Lands Change Detection JUNG RICHARD1*, EHLERS MANFRED1, AND KLONUS SASCHA1,2 1

Institute for Geoinformatic and Remote Sensing, Barbarastr. 22b, 49076 Osnabrueck, Germany 2 Present Address: Nedderfeld 142, 19063 Schwerin, Germany *corresponding author: [email protected] Key words: Classification, Wadden Sea, Change Detection, Multi-sensor The Wadden Sea is a vulnerable ecosystem which is highly influenced by climatic changes and anthropogenic usage of the North Sea. The changes of the Wadden Sea caused by these factors cannot be monitored by the standard measurement methods alone, because access to the tidal lands is often difficult due to tides and unstable underground. For this reason, remote sensing offers effective monitoring tools. In this study a multi-sensor concept for classification and change detection of the intertidal areas in the Wadden Sea has been developed by the Institute for Geoinformatics and Remote Sensing (IGF) of the University of Osnabrueck. Basis for this method is a combined analysis of RapidEye and Terra SAR-X satellite data coupled with ancillary vector data about the distribution of vegetation, mussel beds and sediments. The classification of the vegetation and mussel beds is based on a decision tree and a set of hierarchically structured algorithms which use object and texture features as well as spectral properties preserving fusion techniques. The sediments are classified by a preliminary algorithm which uses thresholds and a majority filter. The resulting classifications were compared in a post classification process to detect changes in the tidal lands area. First results show that the vegetation and mussel beds could be classified by the use of multi-sensor remote sensing data. Classification of sediments in the tidal flats poses a formidable challenge compared to the classification of vegetation and Session VI Marine Habitat Mapping: stretching the blue marble on a map

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mussel beds. Preliminary results demonstrate that the sediments could not be classified by their spectral properties alone. One major reason for this are the different levels of water content in the sediments. For future research, geometric information of the tidal rivers like density, distribution or pattern will be implemented to improve the sediment classification.

Modelling the distribution of benthic species in the Jade Bay in response to environmental change SINGER ANJA1,2*, SCHÜCKEL ULRIKE1, BECK MELANIE3, STANEVA JOANNA5 , WESTPHAL HEIKO4, WURPTS ANDREAS4, KRÖNCKE INGRID1 1

Senckenberg am Meer, Marine Research Department, Südstrand 40, 26382 Wilhelmshaven, Germany 2 University of Bremen, INTERCOAST Research Training Group, Leobener Strasse, 26359 Bremen, Germany 3 Institute for Chemistry and Biology of the Marine Environment (ICBM), Department of Microbiogeochemistry, Carl von Ossietzky University, Carl-von-Ossietzky-Str. 9-11, 26129 Oldenburg, Germany 4 Coastal Research Station - Lower Saxony Water Management, Coastal Defence and Nature Conservation Agency, An der Mühle 5, 26548 Norderney, Germany 5 Helmholtz Centre Geesthacht, Institute for Coastal Research, Max-Planck-Str. 1, 21502 Geesthacht, Germany *corresponding author: [email protected] Key words: Predictive Modelling, Jade Bay, benthic species, environmental change, Wadden Sea

Species distribution models (SDMs) are applied to predict the changes in the distribution patterns of benthic macrofauna species in the Jade Bay (southern North Sea) in response to expected environmental changes due to climate change and harbour effects (Jade-Weser Port). Because of their sessile and sedentary habit, benthic species are important indicators for anthropogenic and environmental impacts. The knowledge of their spatial distribution is an essential requirement to get insight into ecological processes and to guide ecosystem management strategies. To date, SDMs have been under-utilized in the marine ecosystem relative to terrestrial applications. This study provides a contribution for a better understanding of the marine ecosystem that is generally difficult to access and monitor. The model results for the 2009 data offer the possibility to model past and future scenarios. Results for past scenarios are compared with data for the 1930s and 1970s. Invasive species such as Caprella mutica, introduced via ship traffic or aquacultures, are integrated in Session VI Marine Habitat Mapping: stretching the blue marble on a map

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the future scenario modelling approaches as well, aiming to predict their invasive potential in a changing environment. In a final phase, the variability and suitability of different modelling approaches (software used: MAXENT, BIOMOD R package) are compared for the Jade Bay.

Long-term interactions of large scale hydrodynamics, human impacts and sedimentary processes – an integrated multi-technique study BIONDO MANUELA1,2*, BARTHOLOMÄ ALEXANDER2 1

University of Bremen, INTERCOAST Research Training Group, Leobener Strasse26359 Bremen, Germany 2 Senckenberg am Meer, Marine Research Department, Südstrand 40, 26382 Wilhelmshaven, Germany *corresponding author: [email protected] Key words: long-term sediment studies, side scan sonar, acoustic seabed classification, time-series data Over recent years, the lower macro-tidal inlet of the Jade Bay was subject to indirect increasing anthropogenic pressure caused by the construction of the JadeWeserPort in the adjacent tidal channel, and by the related dredging activities. The scope of this study is to present evidence for changes in sedimentary processes, tidal energy, and hydrodynamics that have occurred in response to human impacts. The quantification of the present sedimentary and biological features is accomplished with the use of innovative techniques such as high resolution acoustic remote sensing. The results are compared with time-series records consisting of digitised old classification maps, obtained from previous studies (1969 and 1994), and more recent sediment sampling datasets (2003 to 2011). The high resolution 450Khz side scan sonar data were classified using a texture analysis procedure performed with the SonarWiz™ 5 and the ArcMap™ classification tools. The comparison with the former data was carried out using a geographic information system (GIS). Texture classification performed by both software packages determined six acoustic classes that appeared to be consistent with ground-truthing information on sediment types. The grain size trend suggested dominant sediment pathways that are mainly related to the short- to long-term tide-circulation processes. Comparison with time-series data revealed qualitative changes in tidal driven sedimentation patterns that may be potentially linked to the modification of the channel morphology, although the evidence is not conclusive. The integration of acoustic, sediment and historical data, together with advanced trend analysis, demonstrated to be a sensitive approach for detecting spatial and temporal seabed changes; preliminary results supported the understanding of the tidal system adaptation to human construction and represent a framework for the prediction of future trends. Session VI Marine Habitat Mapping: stretching the blue marble on a map

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Gas related features offshore the Western Pontine Islands (Tyrrhenian Sea) INGRASSIA MICHELA1,2*, MARTORELLI ELEONORA1, BOSMAN ALESSANDRO2, SPOSATO ANDREA2, MACELLONI LEONARDO3, CHIOCCI FRANCESCO LATINO1,2 1

University of Rome Sapienza, Department of Earth Sciences, Rome 00185, Italy CNR (Institute of Environmental Geology and Geoengineering), Rome 00185, Italy 3 Mississippi Mineral Resources Institute, Center for Marine Resources and Environmental Technology, Seabed Technology Research Center, University of Mississippi, 111 Brevard Hall, University, MS 38677, USA *corresponding author: [email protected] 2

Key words: pockmarks, Lebensspuren, authigenic carbonates, bacterial mats, chemosynthetic bivalves Several seafloor depressions have been found on the seafloor around the Western Pontine Archipelago (Palmarola, Ponza and Zannone Islands) located around 30 km away from the Latium coast. By the integration of different geophysical data have been possible to identify specific gas related structures as little pockmarks and large depressions located both on the continental shelf and upper slope. The large depressions are located few kilometers away from the Zannone Island at depths between 105 and 140 m. They have an average surface of 0.25 km 2 and are 10 m deep compared to the surrounding seafloor. Other gas related features have been found in the north-western sector of Palmarola Island (depth between 60 and 90 m), in the southern sector of Ponza Island (depth between 130 and 140 m) and in the northern sector of the archipelago (depth between 200 and 400 m). Video observations (by Remotely Operated Vehicle) acquired across the depressions placed offshore the Zannone Island, were used to ground truth the acoustic facies and allowed us to discover active gas emissions seeping from the seafloor. Evidence of active emissions is also confirmed by the multibeam water-column backscatter data with a strong evidence of several plumes escaping from the sea bottom. In particular these data have revealed the presence of very widespread bacterial mats, isolated chemosynthetic bivalves and a seafloor heavily influenced by the actions of benthic megafauna (Lebensspuren). We also observed the occurrence of particular geological features as small cones and authigenic carbonates (mound and crusts). All these features confirm the presence of an active seepage area that provides the first evidence of cold shallow emissions site in the Tyrrhenian Sea, which hosting such particular chemosynthetic community. Moreover the “fresh” morphology of other gas-related structures indicate the possible presence of additional active emission areas on the seafloor surrounding the Western Pontine Islands. Session VI Marine Habitat Mapping: stretching the blue marble on a map

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Composition, configuration or complexity: spatial metrics to manage disturbed seascapes NOWELL MEGAN S.1*, KALWIJ JESSE M.2, AND SALVATI LUCA3 1

FP7 PEGASO Project, Department of Geography, Universitat Autònoma de Barcelona, 08193, Bellaterra, Spain. 2 Institute of Ecology and Earth Sciences, University of Tartu, Tartu, Estonia; Department of Zoology, University of Johannesburg, Auckland Park, South Africa. 3 Consiglio per la Ricerca e la sperimentazione in Agricoltura – Centre for the Study of Plant-Soil Interactions (CRA-RPS), Via della Navicella 2-4, I-00184 Rome, Italy. *Corresponding author: [email protected] Key words: Seascape ecology, spatial pattern metrics, disturbance, decision-support tool, marine spatial planning The greatest loss of marine biodiversity occurs in the coastal zone, where pressures from both the land and sea combine. Effective management of this unique interface requires quantitative information on the response of coastal ecosystems to changes in environmental conditions and sea use. Spatial pattern metrics, originating from the interdisciplinary field of landscape ecology, provide quantitative information on the structure of the seascape. In this study, we use this tool to identify the aspects of Mediterranean seascape structure that are most sensitive to disturbance. Spatial metrics were calculated for eight typical Mediterranean seascapes in Spain’s Balearic Islands, representing different disturbance and protection levels. The resulting spatial metrics were ranked based on a) shape complexity, b) spatial configuration, c) seascape composition, d) the disturbance score, and finally, c) the protection status. Additionally, a Principal Components Analysis (PCA) was used to explore any underlying relationships between disturbance indicators and spatial metrics. The preliminary results indicated that the study sites with a higher protection status tend to consist of heterogeneous, spatially complex seascapes. We found that seascapes near commercial shipping routes, along densely populated coastlines, or in areas where dumping occurs, consisted of fewer, larger homogenous patches. The PCA confirmed that shape complexity and fractal dimension of patches in particular, showed the strongest correlation to human activity-related variables. These results indicate that protecting the complexity of seascapes should be a priority in disturbed areas. Indeed, complex seascapes provide a greater variety of habitats, thereby supporting higher levels of biodiversity. We conclude that the application of spatial pattern metrics is a useful tool for providing information on which aspects of seascape structure should be managed to protect biodiversity.

Jade Bay surface sediment analysis RITZMANN ANNE Session VI Marine Habitat Mapping: stretching the blue marble on a map

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Coastal Research Station (NLWKN), An der Muehle 5, 26548 Norderney [email protected] Key words: Jade Bay, remote sensing, ground truth, sediment Aim of this study was to create a digital map of the current intertidal surface sediment distribution of the Jade Bay, a shallow tidal basin (172 km 2), located in the Lower Saxony Wadden Sea, Germany (Fig. 1). The predominant sediments of the Jade Bay show a differentiated spatial distribution dependent on the local hydro- and morphodynamics, with a gradient from coarse to fine sediments towards the shoreline. For the current approach high resolution aerial images and sediment samples by means of ground truth were evaluated for the summer of 2009. The photographs, taken at low tide, were visually interpreted in ArcGIS10. The image interpretation was verified with results of sediment core analysis, processed with a laser granulometer and a sedimentation tube in parallel. Sediment classes based on the increasing content of organic material were chosen as light and dark sand, mixed sediment and mud. Furthermore, channels, shells and salt marshes were identified. The classification results were compared with an existing map based on 1996 data. The spatial sediment classification yields to a percentage of 45 % mud, 25 % mixed sediment and 20 % dark sand and 10 % light sand respectively. This basically indicates a stable spatial and temporal sediment distribution for 60 % of the Jade Bay area since 1996, whereas 17 % are characterized by an increase of fine material and 13 % by a loss (6 % changed due to movement of channels and 3 % due to shells). Classification results are in 60 % agreement for image interpretation and sediment samples. Issues were detected in distinguishing mixed sediments from remaining classes due to rather small differences in mud content for adjacent classes. The laser analyser tends to overestimate fine particles compared to the sedimentation tube.

Fig : current surface sediment classification for the Jade Bay, interpretation based on aerial photographs and sediment samples respectively

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Session VII Responses of marine fish to multiple environmental stressors Cornelia Kreiss1 and Katharina Michael1 corresponding author: [email protected] 1

Alfred-Wegener Institute for Marine and Polar Research, Am Handelshafen 12, 27570 Bremerhaven, Germany Fish can be found in nearly all aquatic environments and with 32,000 different species they exhibit the greatest diversity of vertebrates worldwide. They adapted to every possible niche in marine and freshwater habitats during their evolutionary history in the past 500 million years, which is not least due to their highly efficient ion and osmoregulatory mechanisms. These mechanisms enable them to maintain their body fluid homeostasis and thereby all biochemical and physiological processes involved. Therefore fish generally seem to be less sensitive to environmental factors like e.g. elevated PCO2 levels. However because of general constraints on functional capacity the sensitivity to environmental factors might increase if they multiply. This becomes critical with fish being one of the most important food resources for humans, especially in the light of ongoing stock declines all over the world. In this session we would like to discuss responses of marine fish in the context of different natural or anthropogenically generated environmental factors like e.g. temperature, salinity or elevated PCO2 levels.

Contents Talks [time slot] Windisch et al. [12.9.2013; 12.15 pm] INVITED SPEAKER Thermal adaptation in Antarctic fish - trade-offs and limitations in the light of climate change Ghaffari et al. [12.9.2013; 12.30 pm] Study of some biological charcteristics in female Cynoglossus arel Schmidt et al. [12.9.2013; 12.45 pm] Behavioural changes in response to temperature and CO 2 in Polar cod Queiroga et al. [12.9.2013; 1 pm] Session VII Responses of marine fish to multiple environmental stressors

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Natal elemental signatures in the otoliths of Lipophrys pholis (Pisces: Blenniidae) Posters [ID] Windisch et al. [VII.1] Molecular signatures of cold-adaptation in the Antarctic eelpout (Pachycara brachycephalum) Khazaali, A. [VII.2] Effect of heavy metals on blood metabolic parameter of Liza klunzingeri in the Persian Gulf Kegler et al. [VII.3] Stressing coral reefs-combined effects of organic pollutants and ocean warming

Thermal adaptation in Antarctic fish – trade-offs and limitations in the light of climate change Heidrun Windisch1*, Stephan Frickenhaus1, Hans-Otto Pörtner1 and Magnus Lucassen1 1

Alfred Wegener Institute Bremerhaven, Am Handelshafen 12, 27570 Bremerhaven, Germany *corresponding author: [email protected] Key words: molecular cold adaptation, codon usage, amino acid usage, flexibility hypothesis, microarray Since species abundance and distribution in marine ecosystems are mainly driven by the key abiotic factor temperature, it is important to profoundly understand the mechanisms shaping thermal plasticity of organisms to estimate their ability to cope with the ongoing climate change. Specialization to a particular environmental factor can only occur if evolutionary processes develop at a higher rate than the change of environmental conditions. In this case, adaptation opens the prospect of a sustained and successful niche occupation. Such specialization on niches is thought to have developed at the expense of a reduced or even lost ability (“trade-off”) to respond to changing environmental factors. However, ocean warming and acidification, as projected for the future, seriously challenge species that are highly adapted to their habitats as specialists. Within this presentation I would like to focus on mechanisms of evolutionary thermal adaptation in the Antarctic fish fauna through an overview from molecules up to whole animal level. More details are exemplified by species comparisons within the fish family of Zoarcidae inhabiting thermally distinct habitats and therefore providing an excellent Session VII Responses of marine fish to multiple environmental stressors

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model for studies on thermal plasticity. Transcriptomic sequences and their respective translations of the Antarctic eelpout exhibit signatures of molecular cold adaptation when compared to those of its temperate congener, the North-sea eelpout. Trends in the amino acid usage as well as in the codon usage promote a higher flexibility of macromolecules (DNA, RNA and proteins) in the cold. However, such adaptation becomes extremely unfavourable when higher temperatures are experienced. Further indicators for a functional impairment of large protein complexes (translation or transcription) were found through broad-scaled metabolic profiling using a species-specific microarray. These data offer a comprehensive picture which molecular processes are mostly affected by rising temperatures subsequently limiting the ability of such specialized species to acclimate to higher temperatures.

Study of some biological charcteristics in female Cynoglossus arel Ghaffari, H.1*, Ashja Ardalan, A.2, Hosseinzadeh Sahafi, H.3 1

Iranian National Institute for Oceanography (INIO), 9 Etemadzadeh St, west Fatemi Av, Tehran, IR. Iran. 2 Faculty of Marine science and Technology, North Tehran Branch, Islamic Azad University, Tehran, IR. Iran. 3 Iranian Fisheries Research Organization (IFRO), Tehran, IR. Iran. *corresponding author: [email protected] Key words: reproductive cycle, environmental factors, spawning, fish Among the tonguefishes (Cynoglossidae) family, the species of Cynoglossus arel has a wide distribution in the Persian Gulf region. In the present study, the reproductive cycle of C. arel in coastal waters of Bandar Abbas was determined for the first time with regard to the fish reproduction, which is controlled by environmental factors such as temperature and photoperiod. We investigated whether the timing of spawning is linked to sea temperature and photoperiod. A total of 493 females specimens were collected from the coastal waters of Bandar Abbas, south coast of Iran (27˚17’, 56˚26’E), from October 2009 to September 2010, and collated with photoperiod and sea surface temperature (SST). Total length and body weight were recorded in laboratory, while gonads were removed and weighted. The timing and duration of the spawning season was determined from the monthly evaluation of the gonadosomatic index (GSI). GSI values in females were higher between January and April, with the highest mean in February (6.01±0.52) and declined between May and July. There seems to be a resting period from July to September; after this period the gonad weight increased continuously in relation to body weight, with some acceleration around February. The spawning season in Bandar Abbas lasts from February to June 2010, with peak spawning activity from February to March. Five maturity Session VII Responses of marine fish to multiple environmental stressors

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classes were described using ovarian histology throughout the annual cycle to classify the ovaries based on the macroscopic maturity class and external appearance. Comparison of changing SST and photoperiod with fluctuations in GSI showed that in the long warm season of this area, with a late winter and early spring, time of spawning started as SST and photoperiod increased, until it reached its end in late spring (May).

Behavioural changes in response to temperature and CO2 in Polar cod Matthias Schmidt1*, Daniela Storch1, Christian Bock1, Gabriele Gerlach2, Philip L. Munday3 and Hans-Otto Pörtner1 1

Alfred Wegener Institute for Polar and Marine Research, Bremerhaven, Germany Department of Biology and Environmental Sciences, Carl von Ossietzky University Oldenburg, Oldenburg, Germany 3 ARC Centre of Excellence for Coral Reef Studies, and School of Marine and Tropical Biology, James Cook University, Australia *corresponding author: [email protected] 2

Key words: Ocean acidification, temperature, behaviour, fish, polar Since the beginning of the industrial era the concentration of the greenhouse gas CO2 has increased in the atmosphere from preindustrial 280 ppm to current 400 ppm. The Intergovernmental Panel on Climate Change predicts a further increase to 7301020 ppm CO2 till the year 2100 which will lead to a severe change of the worlds` climate. Additionally to the predicted warming, 26% of anthropogenic CO 2 dissolves in the oceans leading to a reduction of 0.2-0.4 pH units till the year 2100 with so far scarcely investigated effects on marine ecosystems. Fish were expected to be resistant against changes in the Pco2 of the ambient seawater as they exhibit an effective acid-base regulatory system. However, recent studies detected drastic CO 2induced behavioural changes in tropical marine fish species. These include impairments in the perception or processing of sensory cues as well as changes in food preference, boldness and lateralization leading to a strongly increased mortality of CO2-treated animals in their natural environment. The physiological causality of these changes remains unknown, but first studies stress that altered functionality of neuroreceptors may play a role in this context. Nevertheless, there is still no information on how ocean acidification will affect the behaviour of cold-water adapted fish species whose slow life cycle may limit their potential for intergenerational adaptation. First results on the behavioural effects of combined CO 2 and temperature in a factorial approach on the Polar cod Boreogadus saida will be presented. Emphasis will be placed on key neurological and behavioral parameters such as lateralization, (re-)activity and aggression. Furthermore, a possible interaction between these two stressors will be discussed. Addressing polar fish species Session VII Responses of marine fish to multiple environmental stressors

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regarding the effects of CO2 together with temperature is crucial as polar regions will experience in the future the greatest increase in both of these factors.

Natal elemental signatures in the otoliths of Lipophrys pholis (Pisces: Blenniidae) Henrique Queiroga1*, Stephen E. Swearer2, Nicole C. Barbee2, Alberto T. Correia3, Roxana Vasile4 1

Centro de Estudos do Ambiente e do Mar (CESAM) and Departamento de Biologia, Universidade de Aveiro, Campus Universitário de Santiago, 3810-193 Aveiro, Portugal 2 Department of Zoology, University of Melbourne, Parkville, 3010 Victoria, Australia 3 Centro Interdisciplinar de Investigação Marinha e Ambiental, Laboratório de Ecofisiologia, Rua dos Bragas, 289, 4050-123 Porto, Portugal 4 EMBC, Université Pierre et Marie Curie - Paris VI, 4 Place Jussieu, 75252 Paris, France *corresponding author: [email protected] Key words: elemental fingerprinting, otolith chemistry, connectivity, larval dispersal This study is part of the broader project LarvalSources which aims to assess the connectivity patterns within the Portuguese network of marine protected areas (MPAs) and between these protected areas and the adjacent coast, using elemental fingerprinting as a mean to validate and refine biophysical individual-based models. Larval dispersal is a fundamental form of connectivity in the marine environment but in spite of its importance to biogeography, population dynamics and resilience, it is little studied and poorly estimated due to the complexity and variability of the multitude of processes involved. One important gap in our efforts is the lack of means to track planktonic propagules back to their origins. In the present study we show that embryonic otoliths of the blennid fish Lipohrys pholis retain natal geochemical signatures that can be used to identify the potential source populations of dispersing larvae. Using laser ablation - inductively coupled plasma - mass spectrometry (LAICP-MS), we measured the concentration of 12 elements (Li, B, Mg, P, S, K, Mn, Cu, Zn, Sr, Ba, Pb) in the embryonic otoliths of L. pholis from 20 sites within 3 regions of the Portuguese coast. We found significant spatial variation in otolith geochemical signatures and showed that these elemental fingerprints can be used to discriminate with a high degree of confidence between sites separated by 10s to 100s of km. The atlas of natal geochemical signatures in the otoliths of L. pholis generated in this study will be used in the construction of empirical connectivity matrices by assigning the recruits of this species to their correspondent natal populations based on the match of their otolith core signatures to the embryonic otolith signatures.

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Molecular signatures of cold-adaptation in the Antarctic eelpout (Pachycara brachycephalum) Heidrun Windisch1*, Magnus Lucassen1 and Stephan Frickenhaus1 1

Alfred Wegener Institute Bremerhaven, Am Handelshafen 12, 27570 Bremerhaven, Germany *corresponding author: [email protected] Key words: codon usage, amino acid usage, flexibility hypothesis, evolution of thermal adaptation, cDNA libraries Evolutionary adaptation and the connected acclimation capacity of species to changing environmental conditions represent key factors in the composition and dynamics of any ecosystem. In marine environments temperature is one of the major driving forces defining the plasticity of the aquatic fauna. Species adapted to stable environmental conditions seem to be especially vulnerable as a trade-off for being specialized to certain conditions. To characterize molecular trends in thermal adaptation, the cold-stenothermal Antarctic eelpout Pachycara brachycephalum was studied by means of sequence analysis of a normalized cDNA library. DNA/RNA sequences and respective translations were compared to orthologs from a eurythermal congener, the Northsea eelpout Zoarces viviparus. Besides a different repertoire of genes in normalized transcriptomes, position-specific interchanges in the amino acid sequence highly conform with the flexibility hypothesis. According to this hypothesis, a protein may be destabilized in its three-dimensional structure by minimal changes within the amino acid sequence. This destabilization sustains reaction kinetics in the cold. In addition, differences were noted in the encoding of amino acids at DNA level. Within homologous proteins of both zoarcid fish, amino acids of P. brachycephalum are encoded with a preference for AT-richer triplets on the third codon position. This trend promotes less stable transitional states at this level, too, as the base pairing of AT is less stable than that of GC. This may facilitate transcription and translation in the cold and thus constituting an adaptation to the cold habitat conditions of the Antarctic eelpout. The observed trends in fish transcriptomes resolve molecular adaptations that differ significantly on the scale of a whole transcriptome even since the mean annual habitat temperature of both fish differ only by 10°K. Such adaptation may also limit cold-stenothermal organisms in their capacity to successfully acclimate to higher temperatures that are nowadays expected also in the Antarctic realm.


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Effect of Heavy metals on blood metabolic parameter of Liza klunzingeri in the Persian Gulf A. Khazaali1* Yung Researchers Club, Islamic Azad University, Bandar Abbas Branch, Bandar Abbas, Iran. P.O.Box:79159-1311 *corresponding author: [email protected] 1

Key words: Heavy metals, metabolic parameter, Liza klunzingeri, Hormoz strait, Persian Gulf. In this study Heavy metals pollution were measured and assessment effect on blood metabolic factors of L.klunzingeri from the coastal water of Persian Gulf. A total of 60 individual Liza klunzingeri were collected from three sites in continental waters around in north of Hormoz strait in November 2011. Samples were used for determining the heavy metals (Zn,Cu,Pb) and blood metabolic parameters. Serum biochemistry determinations included cholesterol, total protein and glucose. The result of this study was show the highest levels of Zn and Pb observed in Boustano Estuary (St3). Total concentration of Zn in Liza klunzingeri of Bandae abbas is very high than of Cu and Pb was showed. In the present study, serum blood total protein and glucose levels of the fish L.klunzingeri exposed to heavy metal pollution station showed increasing. Also, metal exposure caused decreased serum cholesterol concentrations, indicating hypocholesteremia.


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Stressing coral reefs - Combined effects of organic pollutants and ocean warming Pia Kegler1*, Gunilla Baum1, Lisa F. Indriana2, Andreas Kunzmann1 1

Leibniz- Center for Tropical Marine Ecology (ZMT), Fahrenheitstr. 6, 28359 Bremen, Germany 2 Mataram Marine Bio Industry Technical Implementation Unit, Research Centre for Oceanography, Indonesian Institute of Sciences (LIPI), Teluk kodek, Malaka, Pemenang, Lombok Utare, West NusaTengara, Indonesia *corresponding author: [email protected] Key words: Indo-Pacific, reef fishes, climate change, physiological response Coral reefs are ecosystems highly vulnerable to climate change and other anthropogenic impacts. Within the past 50 years global sea surface temperature was increasing steadily, while growing human populations are further stressing reefs around the world. Originating from settlements close to the coast, organic pollutants such as oils and detergents are transferred to the sea. We tested how these pollutants, combined with an increase in temperature, affect coral reef organisms in Indonesia. Experiments were performed on fish (Amphiprion ocellaris and Siganus guttatus) and coral (Pocillopora damicornis) species to measure their physiological responses to the different treatments. The main focus was to identify these responses in the organisms, and to detect possible synergistic effects from the combined stressors. Response parameters in fish included standard and maximum metabolic rates, as well as biochemical indicators such as fatty acid composition, enzyme activities and total lipid and protein levels. In corals respiration, photosynthesis rates and zooxanthellae density were analysed. This study aims to identify the potential threat posed by combined stressors and to give recommendations for future management plans of coral reefs and surrounding areas.


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Session VIII How to integrate blue biotechnology in food industry and medicine Lars Lüllwitz1* and Yvonne Rössner2 1

Fraunhofer EMB Lübeck, Paul-Ehrlich-Str. 1-3, 23562 Lübeck

2

GMA Büsum mbH, Hafentörn 3, 25761 Büsum

Blue biotechnology is, amongst a plethora of other topics, concerned with the application of cellular and molecular biological methods to marine and freshwater organisms. It involves the use of these organisms, and their produced metabolites, for multiple purposes, for example the identification of known and new active ingredients and bioactive compounds from marine origin for the pharma or food industry or the development and use of cell cultures from aquatic organisms for medical or ecotoxicological research. However, the potential for developing products from aquatic life remains mainly undiscovered, due to the enormous diversity of aquatic organisms (many of them unexplored yet). This session aims to shed light on the intriguing diversity of blue biotechnology and its future applications with special emphasis on food industry and medicine. Submissions of abstracts are welcome which deal with any biotechnological method or process related to freshwater or marine organisms. Direct associations with application possibilities for the industry would be advantageous.

Contents Talks [time slot] Straumer et al. [12.9.2013; 12.45 pm] The ACE inhibitor peptide LKPNM in fish Poster [ID] Reichel et al. [VIII.1] Cytotoxicity and antioxidant activity of an extract from brown algae Schwartz et al. [VIII.2] Why are aliens so successful?

Session VIII How to integrate blue biotechnology in food industry and medicine 1

The ACE inhibitor peptide LKPNM in fish K. Straumer1, S. Wittke1*, J. Eysturskarđ2, I. J. Jensen3, A. Kiehne4 1University

of applied Sciences Bremerhaven, An der Karlstadt 8, 27568 Bremerhaven, Germany

2Fiskaaling

F/P, Við Áir, 430 Hvalvík, Faroe Islands

3Norwegian 4

College of Fishery Science, University of Tromsö, Norway

Bruker Daltonik GmbH, Fahrenheitstr. 4, 28359 Bremen, Germany

*corresponding author: [email protected] Key words: LKPNM, antihypertensive peptides, ACE-inhibition, HPLC-DAD, mass spectrometry, fish Background: According to the World Health Organization (WHO), cardiovascular diseases are the number one cause of deaths in Europe. One of the major risk factors is arterial hypertension. Angiotensin converting enzyme (ACE) plays an important role in regulating blood pressure by converting inactive angiotensin I into the potent vasoconstrictor angiotensin II. ACE inhibitors are traditionally used to treat hypertension, but often serious side effects occur. This has raised the issue of natural ACE inhibitors derived from different food sources as a possible alternative to the traditional treatments. One of these natural ACE-inhibitors is the peptide LKPNM extracted from the tuna fish Katsuwonus pelamis [Yokoyama et al. 1992]. Objective and methods: The aim of the study was to detect new natural sources for ACE-inhibitory peptides. Thus, freeze dried muscle tissues of Atlantic salmon Salmo salar, cod Gadus morhua, turbot Scophthalmus maximus and a positive control of the ”Bonito” Katsuwonus pelamis were investigated with regards to their LKPNM content. Syntheticallyproduced LKPNM was used as internal and external standard for identification and quantification by RP-HPLCDAD and RP-HPLC-MSMS after sample preparation. Results: Crude muscle samples of all organisms showed ACE-inhibitory effectiveness already after thermolysin digestion. The analysis of purified, fractionated and freeze-dried samples by LC/MS and LC-MSMS confirmed the presence of LKPNM in all samples, respectively. ACE-inhibitory tests of these fractionated samples are ongoing. In summary new potential natural sources for the ACE-inhibitory peptide LKPNM have been identified. Literature: Yokoyama et al.; Peptide Inhibitors for Angiotensin I-Converting Enzyme from Thermolysin Digest of Dried Bonito; Biosci. Biotech. Biochem., 56 (10), 1541-1545, Japan; 1992


Cytotoxicity and antioxidant activity of an extract from brown algae REICHEL A.*, TWESTEN J., STIEBER R. Fraunhofer Research Institution for Marine Biotechnology, Paul-Ehrlich Str. 1-3, 23562 Luebeck, Germany *corresponding author: [email protected] Key words: Fucus vesiculosus, fucoidan, cytotoxicity, cell culture, antioxidant capacity The brown algae Fucus vesiculosus is one of the main sources for fucoidan. This sulfated polysaccharide is known for various fascinating bioactivities, like antithrombotic, antiviral, antibacterial and antioxidative effects. Fucoidan is also known for causing apoptosis in several cancerogene cells. Therefore, extracts of Fucus species are of significant interest to the pharmaceutical and nutritional industry. While in most studies purified fucoidan extracts have been investigated, we here present the impacts of an unpurified total extract from Fucus vesiculosus (FREEMB) on different cell cultures. To analyse in vitro effects, a standard mouse fibroblast cell line (NIH 3T3) and a long-term cell culture from rainbow trout skin-derived cells (OMYsd1x) were treated with various extract concentrations. Dose-response curves were measured over time using the RTCA xCELLigence ® system (real-time cell analysis). Furthermore morphological differences between these two cell lines after treatment with the extract were determined by microscopy. First results showed cell specific effects caused by extract exposure. Compared to NIH 3T3 cells, OMYsd1x cells reacted very sensitive to the treatment, shown by a decrease in the cell index and by the formation of intracellular vacuoles. In order to determine the mechanisms that led to the observed reactions, two genes were analysed for their expression level in OMYsd1x cells using qRT-PCR. Furthermore the subsequently performed photometric TAA- assay confirmed antioxidative activities in the FRE EMB. Therefore applications of this Fucus vesiculosus extract as an antioxidative additive in food industry is currently under investigation.


Why are aliens so successful? Nicole Schwartz1, Prof. Dr. Peter Schupp1, Prof. Dr. Sergey Dobretsov², Dr. Sven Rohde1 1ICBM, Carl-von-Ossietzky Universität, Carl-von-Ossietzky-Straße 9-11, 26129 Oldenburg

²Marine Science and Fisheries Department, College of Agricultural and Marine Sciences, Sultan Qaboos University, PC 123, Muscat, Sultanate of Oman

corresponding author: [email protected] Key words: biological invasion, invasive traits, secondary metabolites, fouling, algae, feeding deterrence Biotic invaders are species that establish a new area in which they proliferate, spread and persist to the detriment of the environment. In addition to climate change and habitat loss invasive species are considered as one of the greatest threats to local communities and global diversity. Especially invasive algae are of global concerns since over 400 introductions have been reported worldwide. Algae produce a very large variety of chemically active substances that protect them from fouling organisms, deter herbivores or displace competitors. The success of marine bioinvasions may depend on the establishment of chemical defences by the introduced organism. In the present study specific invasive traits should be identified to enable a targeted monitoring and adaptive management. The chemical defense abilities of one invasive species and close, non-invasive relatives were compared by extracting the freeze-dried algae samples and testing their activity in variable assays. The antibacterial activity was tested by measuring bacteria growth in a plate reader and by performing anti-quorum sensing assays. The effectivity of defense mechanisms against other fouling organisms like cyprids, bryozoan larvae, algae gametes and diatoms were compared in different settling experiments. In feeding assays the ability of herbivore deterrence of invasive algae and non-invasive relatives was tested. There were no significant differences in antibacterial activity, but one invasive species inhibited quorum sensing and deterred herbivores more than its non-invasive relatives. In further experiments the compounds responsible for antifeeding and anti-quorum sensing activity should be determined with bioassay guided fractionation and by using TLC, HPLC and GC-MS techniques.


Session IX What’s up with coral reefs? JOOST DEN HAAN1* AND HANNAH J. BROCKE2 1

Aquatic Microbiology Department, Institute for Biodiversity and Ecosystem Dynamics (IBED), University of Amsterdam, Science Park 904, 1098 XH Amsterdam, the Netherlands 2 Max Planck Institute for Marine Microbiology and Leibniz Center for Tropical Marine Ecology GmbH, Celsiusstrasse 1, D-28359 Bremen, Germany *Corresponding author: [email protected] Keywords: coral reef, phase shift, key players, algae, bacteria, sponge It is well known and well documented that coral reefs around the world are degrading (Bellwood et al., 2004; Hughes et al., 2007; Cheal et al., 2010). Human alterations to the ecosystem including eutrophication, chemical pollution, overfishing and coastal build-up can lead to coral reefs becoming overgrown with algae and/or bacteria (McCook et al., 2001), which is often referred to as a phase-shift (Done, 1992). On such reefs, natural competition for space between corals, macroalgae, turfalgae, benthic cyanobacteria and sponges is unbalanced (Fabricius, 2005). Simple topdown and bottom-up studies have in the past provided useful insight into these competitive relationships, but cannot explain the whole story. What actually causes this phase-shift towards algal and bacteria dominated coral reefs? Is it the lack of herbivores that cannot keep algae in check, hence algae can more easily overgrow the reef (Miller et al., 1999; Bellwood et al., 2006; Sotka and Hay, 2009), or is it the increased activity of microbes due to nutrient enrichment (i.e. nitrogen and phosphorus) that promote coral diseases (Bruno et al., 2003), hence corals cannot outcompete algae for space anymore simply because they are sick? It likely is not an or/or scenario, but a combination of both, and possibly more key-players will be unraveled as we increase our knowledge to this ecosystem. It will even be different between various regions around the world, as it is difficult to compare a coral reef in the Great Barrier Reef with for example a reef in the Caribbean. Though our understanding to the functioning of coral reef ecosystems has vastly increased over the last fifty years, new research still stuns scientists on how complex yet fascinating the ecosystem is. For instance, last year Science published a paper by Dixon and Hay (2012) that showed how the hard coral Acropora nasuta calls for help from goby fishes (i.e. Gobiodon histrio and Paragobiodon echinocephalus) once in direct contact with the toxic green macroalga Chlorodesmis fastigiata. As it turns out, A. nasuta releases a specific odor attracting these goby fishes, which then graze upon C. fastigiata. This significantly decreases damage to the live tissue of A. nasuta. Additionally, gobi fishes become more toxic themselves by feeding on C. fastigiata, rendering them less attractive to larger piscivores. Another example of ingenious studies showing the complexity of the systems can be found in the early life stages of coral reef larvae that are trying to find a suitable settlement substrate. Larvae respond to reefs sounds (i.e. from fish and crustaceans) to facilitate detection of Session IX What’s up with coral reefs?

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suitable habitat where they will settle for the rest of their life (Vermeij et al., 2010). Additionally, larvae can detect chemical compounds produced by the benthos to find suitable substrate (Gleason et al., 2009). Conclusively, larvae hear and smell where to settle! These examples indicate the detail of current research on coral reefs, which is vital to properly understand the ecosystem. Early studies focused on a much larger scale using merely taxonomy, ecology and physiology to understand coral reefs, but as the SCUBA industry developed and more marine laboratories were established, research expanded towards reproductive processes, animal-algal symbioses, molecular genetics, ecotoxicology, ecological modeling, calcification, cellular biology and biogeochemistry (Richmond and Wolanski, 2011). Going more into detail vastly increased our knowledge, yet we are still unsuccessful in halting the worldwide coral reef declines (Gardner et al., 2003; Hughes et al., 2003; Mumby et al., 2007; Cheal et al., 2010). Why is that the case? Management and education are one thing but the other could be that we simply do not understand the coral reef ecosystem thoroughly enough yet. Hence, we are often unsuccessful in designing effective management practices. Finding the new key-players will be the challenge of the coming years. Literature Bellwood. D.R., Hughes, T.P., Folke, C., Nyström, M., 2004. Confronting the coral reef crisis. Nature 429, 827833. Bellwood, D.R., Hughes, T.P., Hoey, A.S., 2006. Sleeping functional group drives coral-reef recovery. Curr. Biol. 16, 2434-2439. Bruno, J.F., Petes, L.E., Harvell, C.D., Hettinger, A., 2003. Nutrient enrichment can increase the severity of coral diseases. Ecol. Lett. 6, 1056-1061. Cheal, A.J., MacNeil, M.A., Cripps, E., Emslie, M.J., Jonker, M., Schaffelke, B., Sweatman, H., 2010. Coral macroalgal phase shifts or reef resilience: links with diversity and functional roles of herbivorous fishes on the Great Barrier Reef. Coral Reefs 29, 1005-1015. Dixson, D.L., Hay, M.E., 2012. Coral chemically cue mutualistic fishes to remove competing seaweeds. Science 338, 804-807. Done, T.J., 1992. Phase shifts in coral reef communities and their ecological significance. Hydrobiologia 247, 121132. Fabricius, K.E., 2005. Effects of terrestrial runoff on the ecology of corals and coral reefs: review and synthesis. Mar. Pollut. Bull. 50, 125-146. Gardner, T., Côté, I., Gill, J., Grant, A., Watkinson, A., 2003. Long term region-wide declines in Caribbean corals. Science 301, 958-960. Gleason, D., Danilowicz, B., Nolan, C., 2009. Reef waters stimulate substratum exploration in planulae from brooding Caribbean corals. Coral Reefs 28, 549-554. Hughes, T.P., Baird, A.H., Bellwood, D.R., Card, M., Connolly, S.R., Folke, C., Grosberg, R., Hoegh-Guldberg, O., Jackson, J.B.C., Kleypas, J., Lough, J.M., Marshall, P., Nyström, M., Palumbi, S.R., Pandolfi, J.M., Rosen, B., Roughgarden, J., 2003. Climate change, human impacts, and the resilience of coral reefs. Science 301, 929-933. Hughes, T.P., Rodrigues, M.J., Bellwood, D.R., Ceccarelli, D., Hoegh-Guldberg, O., McCook, L., Moltschaniwskyj, N., Pratchett, M.S., Steneck, R.S., Willis, B., 2007. Phase shifts, herbivory, and the resilience of coral reefs to climate change. Curr. Biol. 17, 360-365. McCook, L., Jompa, J., Diaz-Pulido, G., 2001. Competition between corals and algae on coral reefs: a review of evidence and mechanisms. Coral Reefs 19, 400-417. Miller, M.W., Hay, M.E., Miller, S.L., Malone, D., Sotka, E.E., Szmant, A.M., 1999. Effects of nutrients versus herbivores on reef algae: a new method for manipulating nutrients on coral reefs. Limnol. Oceanogr. 44, 1847-1861. Mumby, P.J., Hastings, A., Edwards, H.J., 2007. Thresholds and the resilience of Caribbean coral reefs. Nature 450, 98-101. Richmond, R.H., Wolanski, E., 2011. Coral research: past efforts and future horizons.In:Dubinsky Z, Stambler N (eds) Coral reefs: an ecosystem in transition. Springer, pp 3-10. Sotka, E.E., Hay, M.E., 2009. Effects of herbivores, nutrient enrichment, and their interactions on macroalgal proliferation and coral growth. Coral Reefs 28, 555-568.

Session IX What’s up with coral reefs?

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Vermeij, M.J.A., Marhaver, K.L., Huijbers, C.M., Nagelkerken, I., Simpson, S.D., 2010. Coral larvae move toward reef sounds. PLoS ONE 5:e10660.

Contents Talks [time slot] Delvoye [13.9.2013; 3.30 pm] INVITED SPEAKER Coral diseases: A story about coral pathology Hassenrück et al. [13.9.2013; 3.45 pm] Effect of ocean acidification on biofilm formation on tropical coral reefs Putchim et al. [13.9.2013; 4 pm] Review of coral reef status in the Andaman Sea, Thailand Robitzch et al. [13.9.2013; 4.15 pm] Genetic Connectivity of the Reef Building Coral Pocillopora sp. in the Red Sea Mes et al. [13.9.2013; 4.30 pm] Light harvesting strategies of benthic cyanobacteria on a coral reef on Curacao Posters [ID] Winkler et al. [IX.1] Influence of bathymetry on macroepibenthic communities associated with the hydrocoral Errina antarctica Brunner et al. [IX.2] Who benefits the most? - Photosynthetic response to light and nutrient enrichment Göhlich et al. [IX.3] Can H S seeps cause death of coldwater corals in Patagonian Fjords, Chile? 2 Bleyenberg et al. [IX.4] Nutrient uptake rates of benthic communities in the Caribbean


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Coral diseases: A story about coral pathology LAURENT DELVOYE1* 1

Carmabi Foundation, Piscaderabaai z/n, Willemstad, Curaçao *corresponding author: [email protected] Key words: coral reef, coral disease, necrosis, apoptosis Educated as a medical biologist at the University of Utrecht, the Netherlands, Drs. Laurent Delvoye specialized in cell biology and microscopical pathology. He worked in the fields of chemical mutagenesis, radiation biology, and oral pathology, and retired several years ago. Since 1980, Drs. Delvoye pursued a parallel career in coral reef biology at the CARMABI Institute on Curaçao, Southern Caribbean, with contributions in the study of coral sexual reproduction, endolithic algae in living coral skeletons, coral tissue fluorescence, and coral diseases. After his retirement, he continued in coral reef science, and specialized in coral histology (i.e., microscopic anatomy of cells and tissues). Coral diseases are a major cause of reef declines worldwide. In the Caribbean for example, coral diseases caused extensive mortality in Acropora palmata and A. cervicornis in the 70s and 80s, causing these species to now be on the IUCN Red List of Threatened Species. In his talk, Drs. Delvoye will explain basic concepts of coral diseases, such as necrosis and apoptosis. He will illustrate common coral diseases including White Band Disease in A. palmata and Montastrea annularis, White Plague in Agaricia lamarcki, and Black Band Disease in Diploria strigosa. Furthermore, he will explain the possible infectious agents that cause them, their etiology, and their role in coral mortality. Many factors in relation to coral diseases are still not well understood, however, despite the present concerns about the future of coral reefs, there is still reason for optimism about the chances of their survival.


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Effect of ocean acidification on biofilm formation on tropical coral reefs CHRISTIANE HASSENRÜCK1*, KATHARINA FABRICIUS2, ANTJE BOETIUS1 AND ALBAN RAMETTE1 1

Max Planck Institute for Marine Microbiology, Celsiusstrasse 1, 28359 Bremen, Germany 2 Australian Institute of Marine Science, PMB 3, Townsville 4810, Queensland, Australia *corresponding author: [email protected] Key words: ocean acidification, coral reef, biofilm, microbial community, settlement Microbial biofilms are a crucial component of coral reef ecosystems. One aspect of their importance is their role in mediating the settlement of higher organisms on previously unoccupied areas and thus in influencing reef community development. Given the threats, especially ocean acidification, coral reefs are subjected to, a better understanding of how microbial diversity and functions may be affected is essential. In this project, settlement tiles were deployed on coral reefs in Papua New Guinea that are characterized by natural CO 2 vents. The location represents an in situ laboratory to study the effects of ocean acidification. Microbial biofilms on the upper and lower sides of these tiles were sampled four and twelve months after deployment. Changes in bacterial community structure were analyzed molecularly using Automated Intergenic Spacer Analysis (ARISA). Preliminary data showed significant microbial community differences between high CO 2 sites and control sites (i.e. sites without the influence of CO 2 vents; ANOSIM, p 35%) at all recording sites. The Ross seal vocal repertoire composition differed between the three recording sites and on a synoptic scale when compared to recordings from other basins. Our findings suggest leopard seals belong to the same ‘vocal clan’ on a regional scale, likely reflecting the spatial scale of distribution during the vocally active period. Ross seals may be more stationary during the breeding season, restricting the spatial scale over which vocal interactions occur, which may result in vocal variation over smaller geographic scales.

Session XII Operational Oceanography

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Session XIV Cephalopods and jellyfish as key species in marine ecosystems: a spatio-temporal multi-scale approach AUGUSTO CRESPI1* and STEFANIE KELLER2 1

Centro Nacional Patagònico (CONiCET), Boulevard Brown 2915, Puerto Madryn (9120), Chubut, Argentina 2

Instituto Español de Oceanografía, Centre Ocenogràfic de les Balears, Mol de Ponent, 07015 Palma de Mallorca, Spain *corresponding author: [email protected] Cephalopods and jellyfish represent an important part of the marine food web, and fluctuation in their abundance will influence other trophic levels directly and indirectly, possibly leading to changing ecosystems. On one hand, many cephalopod species hold relevant fisheries around the world, and changes in their populations therefore additionally have implications for the commercial fishery. With many fish stocks being overexploited nowadays, cephalopods become an even more important resource, also in countries where they have little or not been commercially used before. To avoid a similar overexploitation of these species, which are very short living and often dependent on the recruitment success of only one reproduction season, more knowledge about these animals is needed. Furthermore, in the times of climate change, it is essential to gather time series data of present and past status of abundances and distribution, to be able to compare these baselines with future data. On the other hand, evidence is accumulating that gelatinous zooplankton populations have increased recently in many regions of the world. In many of the world’s oceans and seas, large gelatinous zooplankton such as scyphomedusae and hydromedusae represent a conspicuous component of the plankton, especially during the productive summer months. Over the last decades, there has been a substantial interest in the role that these predatory organisms play in marine ecosystems, especially their effects on lower trophic levels. Generally, jellyfish are detrimental to fisheries because they feed on zooplankton and therefore are both predators and potential competitors of fish and cephalopods, and also because they interfere directly with fishing activity (i.e. saturating bottom trawl gears). The effects of jellyfish population outbursts on ecosystems and the economies that depend on them can be profound, and many factors including climate change, overfishing, eutrophication, and species introductions have been suggested to favour jellyfish populations. In this session, we invite researchers to present studies on several aspects of cephalopods or jellyfish biology, especially those that have considered several scales on space (i.e. variations in biological parameter in different habitats) and time (i.e. population fluctuations related annual fluctuation of environment conditions).

Session XIV Cephalopods and jellyfish as key species in marine ecosystems: a spatio-temporal multi-scale approach

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Contents Talks [time slot] Schröder et al. [12.9.2013; 11.10 am] Would be jellyfishes a new fishing target off south Brazil? Keller et al. [12.9.2013; 11.25 am] The influence of environmental parameters on the abundance of western Mediterranean cuttlefish Crespi et al. [12.9.2013; 11:40 am] Northern Patagonian gulfs (Argentina) as spawning grounds of squids Poster [ID] Crespi et al. [XIV] Young Cephalopod Researchers (YCR)

Would be jellyfishes a new fishing target off south Brazil? RAFAEL SCHROEDER1*, THAÍS RUTKOWSKI1, AND CHARRID RESGALLA JUNIOR1 1

Centro de Ciências Tecnológicas, da Terra e do Mar, Universidade do Vale do Itajaí, Caixa Postal 360, Itajaí, SC, CEP 88.302-202 Brasil. Key words: jellyfish, Rhacostoma atlanticum, south Brazil The jellyfish seems to be common inhabitants of the pelagic marine ecosystem off south Brazil presenting a great interaction to the fishing activity. Itajaí fishing harbor in south Brazil is the main fishing port of the country and the close proximity of the landing sites makes it suitable for a daily fishing monitoring program. Data collection conducted by interviews with the skippers at landing in 317 fishing trips included the fishing area and effort, production of the landed species and an estimative of the jellyfish. For the identification of jellyfish a field guide previously constructed was used and all comments related were also registered between February and June of 2013. Jellyfishes were present in 66 % of the fishing trips and 10 species were recognized by fishermen being Rhacostoma atlanticum the most frequent specie comprising 85% of the cases. Positive Session XIV Cephalopods and jellyfish as key species in marine ecosystems: a spatio-temporal multi-scale approach

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jellyfish records varied between 12-420 meters depth, but were more concentrated around 60m. Qualitative abundance registers varied from "fill up the vessel", "impossible to count", "more than fish" to "seldom", "rare" or "none" or were either quantified in weight according to a common measurement used by fisherman like number of boxes or the capacity of the codend. Impressive values such as 100kg of R. atlanticum per minute were observed in a mid-water trawler. This hydromedusae also presented great interaction with other fishing gears, like other trawlers, bottom gill-nets and purse-seiners. Such interaction was greater during the summer, as corroborated by most of the reports of well experienced fishermen. Most of them said too that jellyfish abundance was so high between 2012/2013 that they need to change the area or operate at night, to avoid large concentrations of jellyfish. Abundance records observed in this year shall be used as reference to verify the fluctuations in the populations of these gelatinous organisms.

The influence of environmental parameters on the abundance of western Mediterranean cuttlefish Stefanie Keller1*, Maria Valls1, Manuel Hidalgo1 and Antoni Quetglas1 1

Instituto Español de Oceanografía, Centre Oceanogràfic de les Balears, Moll de Ponent s/n, 07015 Palma de Mallorca, Spain * Corresponding author: e-mail: [email protected] Key words: Sepia officinalis, life history, environmental factors, Western Mediterranean The cuttlefish Sepia officinalis constitutes an important fishery resource in the Mediterranean, where it is exploited by both the bottom trawl and small-scale fleet. However, there is currently scarce information on the Mediterranean stocks, since most studies on the population dynamics of this species have been undertaken in the northeast Atlantic. In this work we first analyzed different aspects of the cuttlefish life-history from the western Mediterranean such as population structure and reproduction. Secondly, we investigated the effects of different environmental parameters (e.g. climate indices, sea surface temperature (SST), rainfall, chlorophyll-a concentration (Chla) and moon phase) on these populations analyzing several landing time series at different temporal scales. Our results revealed that Mediterranean cuttlefish populations exhibit strong seasonal variations owing to a reproductive migration towards coastal waters. Despite the putative high sensitivity of cephalopod populations to external abiotic factors, our results showed that Mediterranean cuttlefish populations were not affected by most of the environmental parameters investigated. Significant effects were only found for SST and a local climatic index, but no influences were evident for other parameters such as large-scale climatic Session XIV Cephalopods and jellyfish as key species in marine ecosystems: a spatio-temporal multi-scale approach

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phenomena (e.g. North Atlantic Oscillation, Mediterranean Oscillation) or other locallyrelated variables (e.g. rainfall, Chlorophyll a). The moon cycle affected cuttlefish abundances exclusively during the reproduction period, suggesting higher sensitivity during such stressful period as has been reported in many taxonomical groups. Our results also revealed a shift in the cuttlefish population dynamics at the early 1980s, which would be related to important changes in the local hydroclimatology reported by previous authors.

Northern Patagonian gulfs (Argentina) as spawning grounds of squids CRESPI-ABRIL, A.C. Centro Nacional Patagónico (CONICET), Bvd. Brown 2915, Puerto Madryn (9120), Chubut, Argentina. Correspondign autor: [email protected] Key words: Northern Patagonia, sea-water temperature, tidal currents, reproductive areas The spatial distribution of squid paralarvae was studied in waters of San José (SJG) and San Matias gulfs (SMG). SJG is a shallow basin opening to SMG through a narrow mouth located at its northwestern margin, characterized by a remarkable tidal circulation pattern providing contrasting hydrodynamic conditions on its western and eastern domains. During each tidal cycle, SJG ejects 15% of its total volume of water to SMG. This causes that water jets of SJG influence the southern part of SMG. Zooplankton tows (105 in total) and depth-temperature profiling (70 in total) were conducted on a monthly basis at fixed stations forming a regular grid in SJG from October (mid spring) 2011 to March (late summer) 2012. IN SMG, a total of 28 zooplankton net tows were conducted in a regular grid in November 2009 and temperature profiles were conducted in each station. In SJG, temperature-depth profiles showed that while the western domain seawater column stays well mixed by tidal currents during the whole period, stratification develops from November to March at the eastern domain. Positive zooplankton tows were for paralarvae of Doryteuthis sanpaulensis and Illex argentinus. The last were found almost exclusively in the western domain and those from D. sanpaulensis were mainly sampled in the eastern domain. Low abundance of I. argentinus paralarvae in the eastern domain suggests that buoyant egg masses of this squid are not released in SJG; instead they, or the hatching paralarvae emerging from them, could be sequentially advected from and expelled to SMG by tidal currents. On the other hand, the spatial distribution of paralarvae from D. sanpaulensis suggests that those hatching on the shallow marginal bottoms of the eastern domain are retained in this region while those hatching at the western domain are flushed out to SMG by tidal currents.


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Young Cephalopod Researchers Group A dynamic network to connect individual efforts of early career researchers into cephalopod science. Rigoberto Rosas Luis1, Silvia Lourenço 2, Stefanie Keller 3, Augusto C. Crespi-Abril4, Felipe Briceño5 1.- Institute of Marine Science, Barcelona Spain. [email protected] 2.- Centro de Oceanografia, Laboratório Marítimo da Guia, Faculdade de Ciências, Universidade de Lisboa,Avenida Nossa Senhora do Cabo 939, 2750-374 Cascais, Portugal. [email protected] 3.- Instituto Español de Oceanografía, COB, Muelle de Poniente s/n, 07015 Palma de Mallorca, Spain. [email protected] 4.- Centro Nacional Patagónico (CONICET). Boulevard Brown 2915, Puerto Madryn, Chubut, Argentina.Tel/fax: 0054 2965 451024. [email protected] 5.- Institute for Marine and Antarctic Studies (IMAS), University of Tasmania. Private bag 49, Hobart, Tasmania 7001, Tasmania, Australia. [email protected] The Young Cephalopod Researchers (YCR) group aims to improve communication between early career cephalopod scientists, establishing a network and the enhanced collaboration between researchers, and focuses on keeping the members updated on integrated cephalopod research an international level. This platform is led by an interdisciplinary group of young people involved in marine research and working in population ecology, molecular ecology, biological oceanography, physiology, modeling, fisheries, ecotoxicology, environmental pollution and climate change related to cephalopod species. In this context the members of the YCR group want to contribute with further knowledge or fields where cephalopod species are involved and also collaborating and proposing new projects with international participation. The main objectives of particular YCR members vary according to the key species and their distribution in the ocean but the YCR community is conducting research that has some direct connection with climate change, looking for effects of environmental variables in cephalopods. As a result of these initiatives, YCR group has increased the number of members to sixteen people, started cooperation between Argentina and Spain and plans new strategies to affront the development of cephalopod populations under realistic future ocean scenarios. YCR group wants to invite early career researchers to join us in this initiative and unified projects that help us to understand the cephalopod science better.


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Session XV Aquatic Microbes: citizens of a little big world between coast and deepsea Sven Breider and Paul G. Beyersmann Institute for Chemistry and Biology of the Marine Environment (ICBM), University of Oldenburg; P.O. Box 2503; 26111 Oldenburg, Germany Aquatic microorganisms are almost ubiquitous. They can be found either free-living in the water column or particle associated on biotic or abiotic surfaces. But they do not just cover outer surfaces, some organisms are dependent on the mutualism with a number of bacteria whereas other groups can cause fatal diseases. Their diversity is as huge as their impact on the ecosystems, carbon cycling or CO 2 absorption. Wherever they can be found, they are key players for synthesis, transformation and degradation of inorganic and organic matter. The range of microorganisms is extremely wide and varies between specialists for inhospitable environments to generalist, facultative or very adoptable organisms. Even though micro- and molecular biologists nowadays use highly sophisticated methodology and are logistically allowed to go almost anywhere on earth, they hypothesize a high number of bacteria being still not discovered. Therefore this session invites to present new methodological approaches or original research with focus on aquatic molecular biology, microbial ecology, bacterialcommunities, viruses, production of secondary metabolites and phylogeny.

Content Talks [time slot] Jaussi et al. [13.9.2013; 1.45 pm] INVITED SPEAKER Towards the Minimal Energetic Limit in Deep Sediments Lipsewers et al. [2 pm] Aerobic and Anaerobic Ammonia Oxidizers in the Oxygen Transition Zone of Coastal Marine Sediments – A Combined DNA/RNA & Lipid Approach Hoffmann et al. [2.15 pm] Sulfate-Reducing Microbial Community Composition in the Marine Deep Biosphere Wolter et al. [2.30 pm] Diversity and Distribution of Roseobacter clade Bacteria Affiliated with Macroalgae Wienhausen et al. [2.45 pm]

Session XV Aquatic Microbes: citizens of a little big world between coast and deepsea

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Competitive Colonization on Microalgae of Phaeobacter gallaeciensis and Derived Mutants Erler et al. [3 pm] Application of MALDI-TOF MS for Environmental Vibrio Surveillance Programs

Posters [ID] Steinert et al. [XV-1] Cultivation of novel sponge-associated bacteria by using the diffusion-growthchamber approach Ehsanpour et al. [XV-2] Investigation Bioactivity of a Sea cucumber, Stichopus hermanni from Persian Gulf Zorriezahra et al. [XV-3] Isolation and Identification of Yersini ruckeri as Causative Agent of (ERM) Disease in Iranian Rainbow Trout Farms Zorriezahra et al. [XV-4] Investigation on Mortality of wild Golden Grey Mullet associated with (VNN) Disease in the Caspian Sea

Towards the minimal energetic limit in deep sediments? Marion Jaussi1*, Hans Røy1, Kasper U. Kjeldsen1, Bo Barker Jørgensen1 1

Center for Geomicrobiology, Department of Bioscience, Aarhus University, Ny Munkegade 114, 8000 Aarhus, Denmark. *[email protected] Key words: mean cell-specific metabolic rate, microbial activities, limit of microbial life, North Atlantic Ocean, deep biosphere In marine systems, the fresh organic matter from the water column is mainly consumed near the surface of the sediment pile. Therefore the microbial communities living in deep sediments must rely on low amounts of recalcitrant organic matter. The abundance of microorganisms in deep sediments has been estimated to be 3 to 6 orders of magnitude lower than in the surface sediment and the biomass turnover could be as slow as 100 to 1000 years. In the same line, the metabolic activity per Session XV Aquatic Microbes: citizens of a little big world between coast and deepsea

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cell seems to decrease with depth, suggesting that deep microorganisms respire at lower rate than surface microorganisms. Those rates are extremely low compared to what we know from cultured organisms, implying that they possess likely specific physiological characteristics. The present study aims to compare the mean cell-specific metabolic rates from various locations, starting with two sites in North Atlantic Ocean. We measured the rates of community metabolism by reverse transport reaction modeling and quantified the number of extractible cells. The results showed that the total metabolic activities are lower in deep sediments than in the surface. However, the mean per cell metabolic rates do not differ greatly between the sites despite different sedimentation dynamics. Are we approaching the basal power requirement for life?

Aerobic and anaerobic ammonia oxidizers in the oxygen transition zone of coastal marine sediments – a combined DNA/RNA & lipid approach Yvonne A. Lipsewers*, N. Bale, E. Hopmans, S. Schouten, J.S. Sinninghe Damsté & L. Villanueva Department of Marine Organic Biogeochemistry. NIOZ – Royal Netherlands Institute for Sea Research * [email protected] Chemolithoautotrophic organisms make significant contributions to the global carbon cycle and to the availability of nitrogen and sulfur compounds in marine sediments. The present study aims to unravel the spatial/temporal variations in diversity and activity of ammonia oxidizers in marine sediments obtained in three seasonal sampling campaigns in a coastal shelf sea region. We focused on estimating abundance (quantitative PCR, qPCR of gene copies) and expression (qPCR of mRNA and rRNA transcripts) of 16S rRNA genes of Thaumarchaeota (aerobic ammonia oxidizers) and anammox bacteria (anaerobic ammonium oxidizers). Specific intact polar lipids of the target organisms were quantified to support the genetic approach. Results show that both microbes coexist and are active in the oxygen transition zone with seasonal and spatial shifts. The activity of Thaumarchaeota in anoxic layers suggests strategies to tolerate anoxic conditions. Pore water nutrient data (NH 4+, NO3- & NO2-) point to a possible competition for ammonia in the upper 5 cm of the sediment. This study uncovers coastal marine sediments as a potential niche for Thaumarchaeota and anammox bacteria, keyplayers in the marine nitrogen-cycle.


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Sulfate-Reducing Microbial Community Composition in the Marine Deep Biosphere Katy Hoffmann1,2*, K.U. Kjeldsen1, M.A. Lever1, N. Rrisgaard-Petersen1, AND Bo B. Jørgensen1 1

Center for Geomicrobiology, Aarhus University, Ny Munkegade 114 Building 1540, 8000 Aarhus, Denmark 2

Present Address: HGF MPG Joint Research Group for Deep Sea Ecology and Technology, Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, Am Handelshafen 12, 27570 Bremerhaven, Germany *corresponding author: [email protected] Key words: Bering Sea, IODP Expedition 323, deep biosphere, sulfate-reducing microorganisms (SRM), dsrB and aprA genes Although sulfate-reducing microorganisms (SRM) are considered of key importance for anaerobic mineralization in marine sediments, little is known about their identity, diversity and abundance in the deep marine biosphere. Furthermore, we lack knowledge about how microbial community composition in general and SRM community composition in particular are influenced by organic matter availability in sediments and, thus, by the productivity in the overlying water column. In this study the abundance and diversity of SRM at two contrasting Bering Sea subseafloor sediment sites were analyzed and compared to a depth of 405 m below seafloor. Samples were obtained by drilling during the IODP Expedition 323 at water depths of 848 m (Bowers Ridge) and 1,986 m (Bering slope). The rates of water column productivity and sedimentation at these sites were very different. Total microbial abundances were determined by 16S rRNA gene-based qPCR, while SRM were quantified by qPCR of the marker genes dsrB (dissimilatory sulfite reductase βsubunit encoding gene) and aprA (dissimilatory adenosine-5′-phosphosulfate reductase α-subunit encoding gene). The SRM diversity was profiled by cloning and sequencing of the dsrB gene. The abundance and diversity data were evaluated in the context of sediment porewater chemistry as well as lithostratigraphic profiles and microbial activity in the water column. dsrB genes were detected by functional gene PCR far below the methane-sulfate transition zone. The SRM communities consisted of depth-specific clusters but also included phylotypes ubiquitously present across the sediment geochemical zones, thus appearing to be generalists. The results indicated that differences in community composition between sites were small and that community composition did not seem to be strongly related to productivity in the overlying water column.


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Diversity and distribution of Roseobacter clade bacteria affiliated with macroalgae Laura A. Wolter1*, Regina Gohl1, Marco Dogs1, Thorsten Brinkhoff1, Meinhard Simon1 1

Institute for Chemistry and Biology of the Marine Environment, CarlvonOssietzky Straße 9-11, 26111 Oldenburg, Germany *corresponding author. Email: [email protected] Key words: brownalgae surfaces, bacterial biofilm community, Roseobacter clade On a global scale bacteria are among the underestimated wealth of organisms important for life on earth. With their broad metabolic capacities they play a major role in the turnover of nutrients. In marine ecosystems the coastal regions bear the most nutrients as they are inhabited by ample primary producers like macroalgae. The surfaces of these photosynthetic active organisms are covered by a broad number of marine bacteria, often displaying an adapted symbiotic behavior. The bacteria inhabit a special ecological niche on the macroalgae surface and instead provide nutrient compounds suitable for the algae to take up. The αProteobacteria are a major bacterial group present on macroalgae surfaces next to Bacteriodetes and βProteobacteria. Within the αProteobacteria an interesting and abundantly present bacterial group is the Roseobacter clade with a close phylogenetic relatedness among species and on the other hand broad physiological capacities. Although the diversity of different Roseobacter species in macroalgae biofilms was investigated by means of several approaches like DGGE, no detailed phylogenetic study of associated Roseobacter species based on sequence data was performed until now. With our work we filled this gap by establishing Roseobacter specific clone libraries for seven different brownalgae, providing better insight into the different groups contributing to the surface associated community. Furthermore a pyrosequencing approach was used to compare the Roseobacter specific proportional outcomes of the different methods. Most notably a high contribution of four Roseobacter genera in nearly every algae sample was detected belonging to Octadecabacter, Loktanella, Sulfitobacter and Litoreibacter. This basic community of roseobacters was first observed by clone library approach but could be confirmed by use of pyrosequencing. The methods could therefore be assumed as comparable, although a higher diversity of Roseobacter species could be recovered by the pyrosequencing approach.


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Competitive Colonization on Microalgae of Phaeobacter gallaeciensis and Derived Mutants Gerrit Wienhausen1*, Paul Beyersmann1 , Meinhard Simon1 AND Thorsten Brinkhoff1 1

Institute für Chemie und Biologie des Meeres, Carl-von-Ossietzky-Straße 9-11, 26111 Oldenburg, Germany *[email protected] Key words: Phaeobacter gallaeciensis, surface colonization, green fluorescence protein (GFP), acylated homoserine lactone (AHL), tropodithietic acid (TDA) The Roseobacter clade is worldwide distributed, present in diverse habitats and physiological as well as metabolically versatile and therefore an important and intensively studied member of the marine bacterioplankton. Bacteria of the Roseobacter group are believed to be important primary surface colonizers of marine algae. Especially Phaeobacter gallaeciensis DSM17395 was often found in association with algae. Quorum sensing via acylated homoserine lactone (AHL) signaling is most probably influencing the biofilm formation and by the production of inhibitory compounds Phaeobacter is able to outcompete the growth of other bacteria. Plasmids encoding a green- and red-fluorescence gene were designed and introduced via conjugation into P. gallaeciensis wild type (WT) and antibiotic tropodithietic acid (TDA) and AHL production lacking mutants. Plasmid stability tests showed high stability rates after several days of repeating inoculation without selection pressure in P. gallaeciensis. Competitive biofilm formations of P. gallaeciensis WT and mutants will be performed on different microalgae to analyze the effects of the TDA and AHL production on the surface colonization.

Application of MALDI-TOF MS for environmental Vibrio surveillance programs R. Erler1*, A. Wichels1 and G. Gerdts1 Biologische Anstalt Helgoland, Kurpromenade 201, 27498 Helgoland, Germany

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*corresponding author: [email protected] Key words: MALDI-TOF, Vibrio, pathogens Three mesophilic Vibrio species pose a serious threat for humans: V. cholerae, V. parahaemolyticus and V. vulnificus. Due to Global Warming an increase of Vibrio infections is expected in Northern Europe. Hence a fast and cost-effective approach for the identification of those potentially pathogenic strains is needed to evaluate this Session XV Aquatic Microbes: citizens of a little big world between coast and deepsea

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risk. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) fulfills these requirements and is therefore a promising analytical tool for environmental surveillance programs. Creation of a MALDI-TOF MS database filled with 1000 Vibrio reference spectra was crucial for this application. These isolates were characterized simultaneously with approved rpoB sequence data analysis. A comparative examination was performed between rpoB and MALDI-TOF MS. Results reveal that species-specific groups found by the rpoB sequence analysis are equal to MALDI-TOF MS cluster. And congeneric species like V. vulnificus / V. navarrensis can clearly be distinguished from each other. Furthermore mass spectrometric peaks or proteins respectively are getting analysed which are significant for single species. Our goal is to implement this method in Vibrio surveillance programs. First applications show, that MALDI-TOF MS provides valid information about the species composition of environmental samples. However, isolation and cultivation conditions have to be optimized for general monitoring programs and risk evaluation studies.

Cultivation of novel sponge-associated bacteria by using the diffusion-growth-chamber approach Georg Steinert1*, Susanna Whitfield , Michael W. Taylor and Peter J. Schupp 2

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ICBM Wilhelmshaven, Environmental Biochemistry, CvO University of Oldenburg, Emsstraße 20, 26382 Wilhelmshaven, Germany 2 Marine Laboratory, University of Guam, Mangilao, Guam 96923 3 Centre for Microbial Innovation, School of Biological Sciences, University of Auckland, Auckland, New Zealand

*corresponding author: [email protected] Key words: culture-independent, in vivo cultivation, Rhabdastrella globostellata, sponge-specific bacteria, symbiosis Marine Sponges are well known to host dense and diverse microbialcommunities of both biotechnological and ecological importance. The associatedmicrobial community can comprise up to 35% of the total sponge volume. Moreover,some of these microbes appearing to be largely specific to their sponge hosts andseveral of the associated bacteria producing bioactive compounds that are ofpharmacological interest. Hence, the cultivation of associated microbes has been amain focus in search of novel marine products. However, the largest part of theassociated microbial community resist cultivation due to complex biochemical andmetabolic host-specific interactions that are not reproducible using commoncultivation techniques. To address this challenge we adopted the diffusion-growthchamber(DGC) technique to Session XV Aquatic Microbes: citizens of a little big world between coast and deepsea

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isolate possible uncultured and novel spongeassociatedmicrobes. By applying the DGC technique it was possible to cultivate invivo and subsequently isolate known and novel bacteria in vitro. We obtained morethan 260 16S rRNA sequences during this study. Blast analysis of sequences againstthe NCBI database resulted in identification 5 novel OTUs at 0.03 genetic distancecut-off and 97% 16S shared sequences identity with any previously culturedbacterium. Altogether, we cultivated strains which belong to four known phyla:Actinobacteria, Bacteroidetes, Firmicutes and Protebacteria (Alpha and Gamma).Furthermore, we assessed their possible monophyletic positions within spongespecificphylogenetic trees. Here, we present an analysis of DGC-derived bacterialstrains, and report evidence for sponge specificity of some strains.

Investigation Bioactivity of a Sea cucumber, Stichopus hermanni from Persian Gulf Maryam Ehsanpour *1, Majid Afkhami 1, Zahra Khoshnood2, Reza Khoshnood3 1

Islamic Azad University, Bandar Abbas Branch, P.O.Box:79159-1311, Bandar Abbas, Iran. 2

Islamic Azad University, Dezful Branch, Dezful, Iran.

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Islamic Azad University, Centeral Tehran Branch, Tehran, Iran.

*corresponding author: [email protected] Key words: antibacterial, antifungal, cytotoxic, Stichopus hermanni, Persian Gulf. Within the frame of a biodiversity and bioactivity study of marine macro organisms from the Persian Gulf, Stichopus hermanni a sea cucumber species extracts were investigated for cytotoxic, antibacterial and antifungal activities against five human pathogenic microorganisms. All concentrations of extracts showed no antibacterial activity towards the tested strains. In antifungal assays the sea cucumber extracts showed significant activity solely against Aspergilus niger with MICs ranging from 3 to 15 μg/ml. The highest antifungal activity was found in body wall (MeOH) extract with an inhibition zone of 38 mm against A. niger at 18 μg/ml extract concentration. Body wall and Cuvierian organ extracts of this species exhibited cytotoxic activities. It is important for future research to concentrate on finding the mechanisms employed by sea cucumbers to defend themselves against invasion, the mechanism of infections and the type of chemical compounds in S. hermanni extracts that inhibit antifungal growth or proliferation in less exploited areas such as the Persian Gulf.


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Isolation and identification of Yersini ruckeri as causative agent of (ERM) disease in Iranian rainbow trout farms Mohammad J. Zorriehzahra1*, Mehrdad Amirikar2, Abbas A. Motallebi1, Daryoush Azadikhah2, Shapour Kakoolaki1, Ali Nekouifar3 AND Nima Behoudi2 1

Iranian Fisheries Research Organization (IFRO), Hemmat highway, Paykan shahr, Sarve Azad, Ave., West 8th St., Botanical National Blvd. Tehran, Iran, 2 Islamic Azad University- Branch Uremia, Iran 3 Artemia References Research Center,Uremia, Iran *corresponding author: [email protected] Key Words: Iran, Coldwater fish, Enteric Redmouth Disease Coldwater fish products have been developed in recent decade and total rain bow trout fresh meat reached to 130 thousand MT in 2012. Infectious diseases with emphasis on viral and bacterial diseases are responsible of high mortality and economic lost in aquaculture. Enteric Redmouth Disease (ERM) has been reported as second important infectious bacterial disease in Coldwater fish farms according to recent official records of Iranian Veterinary Organization. In order to isolate and identify the pathogenic bacterium in affected farms during April- August 2012, sampling procedure was done from 285 rainbow trout weighing from 1-200 g up, from 18 coldwater farms that located in West-Azerbaijan province. Samples from the fish's mouth, kidney tissue, and the last third of intestine were cultured on Yersinia selective agar media and then plates were kept in the incubator at the 25°C for 48-72 hours using gram staining and biochemical tests in the laboratory experiments and PCR method for molecular study. Regarding to our findings about 110 samples were infected to Yersinia ruckeri in the intestine (With an average of 59/38% contamination), 76 in mouth (With an average of 25/66% contamination), and 25 in kidney tissue (With an average of 8/77% contamination). Moreover, from 5 farms out of 19 studied farms in West-Azerbaijan Yersinia ruckeri bacteria were isolated so the contamination about 36.84 percent was estimated. The results show that the average amount of contamination in West-Azerbaijan is higher than other provinces in the country. In conclusion, according to different weights, the samples in finger size weighing 1-20 g were the most infected ones, and the ones in market size weighing up to 200 grams had minimal contamination with bacteria Yersinia ruckeri. This result revealed that fish with low weights and small sizes are more sensitive than the others with high weights and large sizes.


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Investigation on Mortality of wild Golden Grey Mullet associated with (VNN) Disease in the Caspian Sea Mohammad J. Zorriehzahra1*, Mohaddes Ghasemi2, Maryam Ghiasi3, Alireza Nazari4, Somayeh H. Karisidani5, Giuseppe Bovo6, Hassan HJ. M. Daud 7, Mehdi Soltani8 AND M.S. Rohani1 1

Iranian Fisheries Research Organization, (IFRO), Tehran, Iran Inland Water Aquaculture Research Center, Bandar Anzali, Iran 3 Mazandaran Fisheries Research Center, Sari, Iran 4 Islamic Azad University, Falavarjan Branch, Isfahan, Iran 5 Sturgeon International Research Institute, Rasht, Iran 6 Instituto Zooprofilattico Sperimentale delle Venezie , Padova, Italy 7 Faculty of Veterinary Medicine, University of Putra Malaysia (UPM), Malaysia 8 Faculty of Veterinary Medicine, University of Tehran, Iran *corresponding author: [email protected] 2

Key Words: Iran, Viral Nervous Necrosis, Golden Grey Mullet, Caspian Sea

Unknown mortality had occurred in wild mullet in the Caspian Sea since 2003. About 322 moribund fish samples were collected in 2007 till 2010. Suspected fish revealed skin darkening, erratic swimming behavior such as spiral and belly-up at rest and high distention of swimming bladder. Brain and eye were removed in strile condition and then kept in -80oC frezzer for cell culture and Nested-RT-PCR. Tissue samples were taken and fixed in 10% buffer formalin and glutaraldehyde 3% for histopathology, IHC and EM respectively. CPE was observed six days in monolayers of SSN-1 cell line. It was characterised by thin or rounded, refractile, granular cells with vacuoles. Nested- RT-PCR was done on suspected tissue samples and supernatant of CPE positive samples and 21 tissue samples and all CPE positive samples were positive. IFAT as a confirmatory test for identifying viral strains replicating on cell cultures carried out with rabbit anti-betanodavirus serum on suspected tissue samples and some smears of CPE positive samples. Some bright points approved betanodavirus and confirmed findings. Widespread and massive vacuolation were observed in brain, spinal cord, retina and optical nerve. In confirmation of diagnostic findings, IHC was done with monoclonal antibody antibetanodavirus and some red-brown points were observed. Moreover, virus particles with 25-30 nm in diameter were visualized in infected brain and retina using positive staining in TEM. Also pathogenicity test was employed to confirm the obtained results. Guppy fish (Poecilia reticulata) were used instead of the experimental host due to ease of handling and susceptibility. After 15 days post infection, guppy bathed in VNN-infected tissue culture with 104 TCID50 showed clinical signs similar to naturally infected mullet, and the mortality rate reached up to 100% in 75 dpi. In conclusion, VNNV was the main causative agent for outbreak in Golden grey mullet in the Caspian Sea.


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