recorded, The common octopus (Octopus vulgaris) is the octopoda most common off the coasts of the Azores. The species is highly appreciated and caught by ...
Higher Education Policy Vol. 8, No. 2, 1995
25
Marine Research: The Role of the Department of Oceanography and Fisheries of the University of the Azores Ricardo Serrão Santos, João Gonçalves and Eduardo Isidro INTRODUCTION
AZOREAN FISHERIES
The archipelago of the Azores, which defines around 60 per cent of
The most economically important fishery in the Azores besides the tuna fishery (Pereira, 1990, 1992), which supports the canfling industry, is the bottom longline and handline multi-specific fishery. Besides blackspot seabream (Krug, 1987, 1989, 1990; Krug and Silva, 1990), the most significant catches are the bluemouth rockfish (Isidro, 1987a, l987b, 1989), the forkbeard (Silva, 1985, 1986a, 1986b, l987b; Silva and Krug, 1992) and the conger eel. Longlines are mostly used by open-deck boats of lengths
the Portuguese Economic Exclusion Zone, or EEZ (the largest within the 12 EU countries), has been implementing strong efforts in view of developing its research on marine sciences, namely fish-
eries, based in the Department of Oceanography and Fisheries (DOP) at the University of the Azores. Since its foundation, the DOP has resorted to different kinds of external cooperation. The singular characteristics of the Azorean EEZ (with 1 million km2) and the marine environment of this archipelago determine the existence of specific problems in the sector of research, which implies an added effort (technical, scientific and financial) to guarantee the sustainable development of the fisheries through an adequate management of the resources (Martins, 1986; Alves, 1990, 1992; Silva, 1992). This sector is most important, since on
it depends the development of the fisheries industry, whose social and economic weight in the region is high. At the same time, it constitutes one of the few examples of diversification of the economic activity on the archipelago. Aware of this need, the DOP has developed the implementa-
tion of distinct interdisciplinary lines of fundamental and applied research in marine sciences since 1979 in the region of the Azores. It now boasts a staff of around 30 people (including scientists, technicians and administrators) working full time in the fields of marine ecology and biodiversity, behavioural ecology, fisheries biology and stock assessment, chemical and physical oceanography, marine chemistry and pollution (see Table 1). The 1980s defined a new dimension of scientific research in the Azores. At the University of the Azores, which was created by the end of the 1970s, scientists initiated their research into different areas of the natural history of the archipelago. The University also became a centre of attraction for reinforced scientific cooperation with other marine research institutions, both national and foreign. Scientific production (Martins, 1990) has also increased largely.
80 976: tjnivcreity ofihe Azores was created
70
Other srnhjeeto
60
Filn
greater than nine metres and larger cabinned boats. Smaller open-deck boats usually use handlines.
The annual landings in the Azores have been increasing since 1983, due to the progressive arrival of new, more efficient, covered-deck boats. The expansion of the fishing effort has been encouraged by better preservation plants and expanded export markets. Both old and new areas have been exploited. There has been a general tendency for the decrease of small open-deck boats and an increase of covered-deck boats. The increase in fishing effort and the greater distances being fished offshore have put considerable pressure on the demersal
fish assemblage. A variety of species (at least 30) are caught, including some less-favoured, low-price or 'trash' species. This fishing activity will probably restructure the benthic food web. Officially, fishing is confined to traditional lining, with the exception of large-mesh nets used for the deep-water shark. Much small-scale artisanal fishing exists in the Azores, and much of it is on a part-time or seasonal basis. This is also the case
of the exploitation of crustacea and molluscs, particularly the winter squid fishery (Martins, 1982; Martins and Porteiro, 1988; Porteiro, 1990; Porteiro and Martins, 1994).
SPECIES CONSERVATION AND LEGISLATION Azoreans have always heavily exploited their littoral and nearshore waters, posing considerable problems for both resource management and nature conservation in recent years (Martins and Santos, 1991; Santos, 1992). Their importance for the local economy is or has been significant in some cases. In general, exploitation pressure increased with the ready availability of cheap snorkelling gear in the 1970s. Collection using SCUBA (self-contained underwater breathing apparatus) gear is banned, except for scientific purposes by authorized personnel.
Oilier ir,vertelnn InICO
j
30
(2g-n u lu e e u
20
Molcrcu
Limpets (lapas): Two species of limpets occur in the Azores: lapa
w Algue
0L o'
o' o'
o' o'
o
Figure 1. Publication profile for the Department of Oceanography and Fisheries
MOLLUSCS AND CRUSTACEA brava, the 'wild limpet', and lapa mansa, the 'tame limpet' (Hawkins et al, 1991). Lapa mansa inhabits the inter-tidal zone, occasionally being found sub-tidally, while lapa brava occurs low on the shore and in the upper sublittoral to six metres deep, very exceptionally reaching 15 metres. Both species occur together in the upper and lower limits of their distribution. Lapa mansa is mainly exploited on a subsistence or recreational basis, while lapa brava has been exploited mainly by both licensed and unlicensed
skin divers, depending on the island concerned. A full-time
26
Marine Research
Table 1: Abstracts of some of the research projects at the Department of Oceanography and Fisheries at the University of the Azores Project
Time Period
Coverage
Parameters
Summary
Database of the Azorean fisheries
Landing
Azorean EEZ
Nominal landings (biomasa) of the Azorean fisheries, by species, island, harbour, boat with fishing methods and effort. Fisheries statistics (catch and effort), biological statistics on size frequencies and other biological parameters. Catch and effort statistics, morphometric statistics (length, weight), reproduction, trophic habits, growth, tagging experiments Oceanographic and biological conditions associated with catches.
Biological and statistical data of the swordfish fishery in the Azores Biology and fisheries of the
From 1980 Azorean EEZ onwards (catch); from 1984 to present (biological) Since 1982 Azorean EEZ
most important sharks Checklist of the marine fish of the Azores
To present
The pelagic fishery of tunas and horse mackerel and demersal fishery are the two main groups in the Azorean fisheries. The landings of demersal fishery have been increasing in recent years, reaching almost 4,000 metric tons (MT). This increase is due to the effort made in the development and modernization of the fleet. Fisheries statistics (catch and effort), biological statistics on size frequencies and other biological parameters for the main Azorean exploited species (pelagic and demersal fish, and some invertebrate species) are collected in the major landing ports. Other biological data (morphometric, reproductive and alimentary) are available for some of the species in a monthly base. Tunas represent the main fishery in the Azores, with annual catches from 12,000 to 15,000 MT. Biological sampling started in 1980; data are regularly collected. Swordfish is a recent and growing fishery in the Azores, with annual catches around 500 MT. Biological sampling and fishery data are regularly collected. Collection of data includes other billfishes. Growth, reproduction and assessment of the Azorean stock of kitefin shark, Dalatias licha, was studied in most detail. The study of blue shark, Prionace glauca, was initiated in 1993. A complete catalogue of the marine fish of the Azores, with general information of each family and each species given. All references regarding species location in the Azores are given. Original drawings and photographs are presented. Study of seasonal, sexual and ontogenetic variations of energy allocation on organs and tissues. Reproductive strategies, individual differences, behavioural effort, ethogram, homing and Orientation, mobility and the use of space. Studies mostly concentrate on blennies, gobies, clingfish and wrasses. The study of the limpets (Parella spp.) was developed to evaluate the state of the populations of limpets on the archipelago of the Azores. The clam population (Rudirapes decussatus) of the coastal lagoon of 'SantoCristo' on S. Jorge Island is exploited artisanally, being of high local importance. Data on the morphometry and reproduction of this species have been regularly recorded, The common octopus (Octopus vulgaris) is the octopoda most common off the coasts of the Azores. The species is highly appreciated and caught by diving. Maturation and spawning occur all year round, with two peaks: a lower in May and a higher in September. Crustacea, mainly crabs, are the most important food items in the diet. The sea urchin, Sphaerechinus granularis, is a common species, in the littoral area of the Azores, between the 10 to 40m depth. The colour,
statistics: since 1972 Biology: since 1979
36N-41°N;
Catch and effort statistics, morphomemc statistics (length, weight), reproduction, trophic habits, growth. Length, sex ratio, reproduction, age and growth, catch data, fishing gears.
23°W-32°W
Taxonomic species, distributions, biology and ecology.
Ethogram, home ranges and territories, homing ability, gai, hsi, condition factors, feeding.
Biology and behavioural ecology of littoral fish
Since 1984
Coasts of the Azorean islands
Biology, ecology and exploitation of selected coastal invertebrates with commercial value: molluscs (limpets, clams and octopus), crustacea (locust lobster) and others (eg, sea urchins)
Since 1985.
Limpets: coastal Morphometry (length and weight), shores of all the reproduction (sex and maturity islands of the stages) and growth data on regulararchipelago of the ly sampled limpets (Patella spp.). Azores. Clams: Study of abundance and population 'Santo-Cristo' dynamics based on standardized coastal lagoon, sampling methods. Recruitment S. Jorge Island, and environmental conditions. Azores. Octopus: Azorean EEZ, mainly Faial and São Miguel. Locust lobster: coasts of the islands of Pico and Faial. Sea urchins:
Locust lobster: 1982 to 1990. Sea urchins: since 1991.
Faial and São Miguel.
diameter, wet weight, sex and gonad weight are recorded.
Biological data of the sea turtles of the Azores
From 1984 onwards
EEZ of the archipelago of the Azores
Tagging, morphometric and physiological data.
Ecological data of the seabirds of the Azores Diet items of large predators and mercury contents of muscle tissue Database of bibliographic references on marine biology of the Azores Database of bibliographic references on cephalopod documents available at DOP
Since 1989
Azorean EEZ
Distribution, abundance, conservation status, biology and
From 1981 to
Azorean EEZ
Diet items in the stomach contents of large predators, evaluation of mercury in the muscle tissue.
To present
Azorean EEZ
Bibliography.
To present
Worldwide references
Bibliography.
Juvenile loggerhead sea turtles found in the Azores are believed to be from the breeding colony that nests on the beaches of the south-east United States, primarily in Florida. Previously, there has been no systematic study of sea turtles in the pelagic habitat; 1,061 turtles have been tagged to date. Aspects of the biology and ecology of some species of seabirds of the Azores have been studied.
ecology. 1992
This study is the first attempt to obtain a detailed analysis of the oceanic food web near a mid-Atlantic island by studying the diets of a large section of the larger predators, many of which are commercially important pelagic fish. A list of 144 references to the marine fauna and flora within 200 miles of the Azores has been compiled. Papers concerning marine mammals, turtles, birds and large pelagic fish are not included. The biology and fishery of cephalopods (squid and octopus) are one of the main subjects in the research of the Marine Ecology section of DOP. Almost 2,000 documents on this subject have been stored in the DOP library during the last years. The references of those documents have been stored in a software database.
Ricardo Serrão Santos, João Gonçalves and Eduardo Isidro 27
professional fishery was present in Sâo Miguel until 1988 (Martins et al, 1987; Santos et al, 1990).
MARINE MAMMALS
Clams: Tapes decussatus is the only clam commercially exploited
in the Azores (Santos and Martins, 1987; Santos et al, 1989;
Occurrences
Gonçalves and Martins, 1991; Gonçalves et aI, 1993). It occurs only in a small lagoon on S. Jorge Island, which is a protected area. Its commercial importance was local until it gained a gastronomic status that also reached the other islands.
Nineteen to 21 species of cetacea are known in the Azorean waters, belonging to five families (Reiner, 1990; Reiner et al,
Crustacea: The locust lobster (locally called cavaco) is a highly esteemed crustacean in the Azores, where it is considered a delicacy (Martins, 1985). There is a closed season and size limit. The giant barnacle is a species highly appreciated locally as seafood.
Data on the fisheries' efforts and capture do not exist, as the exploitation is very artisanal and the barnacles are sold directly from the fisherman to the consumer.
Common octopus: Fourteen species of octopoda occur in the Azores (Gonçalves, 1991a). Due to the fact that the catches tradi-
tionally escape control of the authorities, very little is known about the actual level of exploitation (Gonçalves, l991b, 1993). There are reasons to believe, however, that the stocks are diminishing on the main islands. It is also likely that there has been a switch from limpet collecting to octopus collecting because of the ban introduced on collecting limpets in the central and eastern islands in 1989.
FISH
1993). Also, two species of pennipides have been recorded, Phoca
vitulina and Phoca hispida (LeGrand, 1981), but these are very exceptional. Of these sea mammals, ten are included in the Red Book of Portuguese Vertebrates.
EXPLOITATION AND CONSERVATION The 18th-century whaling around the Azores was practised by British ships based in New England (Clarke, 1954; Gaihardo, 1990). In the middle of the last century, whaling based in the Azores was initiated as a commercial activity. Up to 200 small boats were hunting the sperm whale at one time. Whaling in the Azores evolved as a near-shore activity. Methods were always tra-
ditional, using small, open boats. The contribution of Azorean whaling in the world context, solely concerning sperm whales, was always very low. In the 1960s, whaling started decreasing and commercial whaling ceased completely; after that, only two individuals were caught in 1987. At first the declining importance of whaling was mainly related to the growth of other fishing activities, like tuna fishing and demersal fishing.
Dolphins were also hunted in the Azores, both for human consumption and fishing bait. This has stopped. In 1983 a law was approved in the Regional Parliament protecting four species
Coastal fisheries: There is considerable recreational and semisubsistence fishing using rod and line or handlines from the coast and close inshore from small boats. Furthermore, there is considerable spearfishing activity. The dusky perch is the only fish under special regulation in the Azores. Spear guns cannot be used to catch this grouper; however, traditional fishing using hooks is permitted. This species is still quite abundant, and the
catus and Grampus griseus. Total protection of sea mammals in the Azores was only defined in 1989 by a central government law which adopts and extends the Bern Convention to continental Portugal, the Azores and Madeira. Common dolphins (eg, D. delphis and T. truncatus) are, apparently, highly abundant in the
fishery is growing.
area.
Several other species of labrids, like moray eels, sparids, the red mullet and the parrot fish, are exploited. However, the most important of all species, habitually fished close to shore, is the juvenile of a pelagic fish, the blue jack mackerel, the most impor-
RESEARCH
tant commercial species in the Azores besides tuna. Despite growing exploitation, stocks were still good until recently (Isidro,
1988, 1990a, 1990b). Demersal fisheries constitute one of the most important commercial activities in the Azores. There are no special regulations such as minimum sizes or closed seasons for
exploited demersal species in the Azores, while in mainland Portugal, 25 demersal fish have special regulations. Officially fishing is confined to traditional lining, except for the case of the juveniles of the Pagellus species and Trachurus picturatus, used as live bait, and the deep shark Scymnorhinus (Silva, 1983, 1987a). Clearly, regulations need to be introduced on a species-by-species basis.
Marine turtles: Five species of turtle have been recorded in the Azores: loggerhead, green turtle, hawksbill, Kemp's ridley and leatherback, of which only the loggerhead is encountered frequently, the others being very rare (Bolten and Martins, 1990; Bolten et al., 1992, 1993). The Azores are particularly interesting for doing research on the loggerhead, the most common species. An important joint programme of research on pelagic turtles (mainly loggerheads) is being carried out by the University of the Azores' Department of Oceanography and Fisheries. Between 1984 and 1992, 1,061 turtles were tagged. They were captured at
sea by tuna boats and brought to the DOP, where they were tagged and then released again into the sea. The main threat for sea turtles at sea are oceanic pollution (like oil and tar) and floating rubbish (like plastics, polyethylene, styrofoam, etc), which they eat (Carr, 1987). Unfortunately, marine debris is common, even in the waters surrounding the Azores.
of cetaceans: Deiphinus delphis, Stenella coeruleoalba, Tursiops trun-
The first studies on sea mammals from the Azores were made by the research team of Prince Albert I of Monaco (Richard, 1910, 1936). Current research involves feeding habits, physiology and social behaviour. Since 1987, Jonathan Gordon (Gordon et al, 1987, 1988, 1989) and his team have been coming to the Azores every summer. Their research has greatly increased the know-
ledge on sperm whales' social behaviour and communication,
abundance and distribution of several species of cetacea, acoustics applied to cetacean detection and calculations of group size and individual size, plus photo identification. Another aim of the programme was to study the interest and biological feasibility of whale watching in the Azores (Henson et al, 1989). A
small, but active, enterprise is now established at Lajes (Pico Island).
CONCLUSION Much basic marine ecological, systematic and biogeographic research is required to place the Azores into its proper context in the north-east Atlantic. Some groups have been well studied (eg, algae, fish, amphipods, decapods, tunicates) and biogeographic conclusions can be made; in others, there are huge gaps. There is also a need for further basic survey work to describe major habitats and communities (biotopes) throughout the archipelago. Of particular interest are the various seamounts in the area. Some interesting communities surrounding volcanic springs and vents
were recently discovered at around 1,700 metres depth (Langmuir et al, 1992, 1993). The Azores also constitute an area with the best potential for studying both shallow and deep vents
28 Marine Research in the mid-Atlantic Ridge. Shallow-water hydrothermal vents are known on the João de Castro seaniount and at São Miguel (Zillig et al, in press).
NOTES Detailed information about references may be obtained from the authors at the Department of Oceanography and Fisheries, University of the Azores, 9900 Horta (Açores) Portugal.
