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Document prepared by: Dr Rhett Bennett: ƌŚĞƚƚΛŵŽǀŝŶŐƐƵƐŚŝ͘ĐŽŵ Mike Markovina:ŵŝŬĞΛŵŽǀŝŶŐƐƵƐŚŝ͘ĐŽŵ
African Marine DĞŐĂTransect ǁǁǁ͘ŵŽǀŝŶŐƐƵƐŚŝ͘ĐŽŵ
1. Rationale Coral reefs Coral reefs are highly diverse, highly productive ecosystems (Done et al. 1996, Moberg and Folke 1999, Graham et al. 2008). They are able to support huge, intricate food webs, from tiny microorganisms that live within and build the reef, to top level predators, thereby supporting a high biomass. In so doing, coral reefs contribute an estimated US$ 375 billion annually, in terms of their value to the biosphere (Souter and Lindén 2000). Coral reefs also provide a wealth of functions, ecological services and goods to people in coastal areas (Cesar 2000), including food security for millions of people in coastal communities (Obura and Grimsditch 2009). As a result, they are considered “one of the essential global life support systems necessary for food production, health and other aspects of human survival and sustainable development” (UNEP/IUCN 1988). Owing to their valuable resources, coral reefs support vast fisheries in many parts of the world. However, as the global human population continues to rise, particularly in coastal areas, harvesting effort on coral reefs is increasing at an unsustainable rate (Hodgson 1999, Fenner 2014). In addition, coral reefs face severe threat from climate related sea temperature rise and ocean acidification (Donner et al. 2005). Consequently, many coral species face a high risk of extinction (Carpenter et al. 2008). By 2008, an estimated 19% of the world’s coral reefs had already been ‘effectively lost’, meaning that they are comprised of few live corals, and have been seriously overfished, with few large predators and algal grazing fish (Wilkinson 2008). A further 15% is thought to be in a ‘critical’ state, and may become ‘effectively lost’ within the next two decades, while 20% is considered to be in a ‘threatened’ state, with potential loss in the next 20 to 40 years (Wilkinson 2008). The East African coral reef ecosystem The coral reefs of East Africa contribute significantly to coastal productivity in the south Western Indian Ocean (Lindén et al. 2002). These reefs have long provided valuable resources for coastal communities, including a rich source of food and foreign currency generation through tourism, and a large number of people depend on these resources for their livelihoods (Bergman and Öhman 2001, Lindén et al. 2002). Coral reefs support an estimated 7 million people in coastal communities in Mozambique, as well as major artisanal fisheries and tourism industries in Tanzania and Kenya (Muthiga et al. 2008). However, East Africa’s coral reefs have suffered high levels of bleaching and are under severe threat, with some of the greatest proportions of “critical stage” coral reefs worldwide (Wilkinson 2008). East African coral reefs have exhibited widespread damage since the early 1980s (UNEP 1992), and since then the condition of these reefs has further deteriorated (Lindén et al. 2002, Graham et al. 2008). Overfishing and destructive fishing can have detrimental impacts on coral reef ecosystems. Major ecological impacts can occur through overfishing, such as changes in community structure where the removal of algal grazers can result in coral communities being replaced by algae (Wilkinson et al. 2003). Destructive fishing practices, such as blast fishing and netting, can have devastating effects on the fish community and on the coral reef itself (Souter and Lindén 2000, Wilkinson et al. 2003). These activities have resulted in severe reductions in biomass (sizes and numbers) and changes in fish community structure in this region (Wagner 2004).
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Despite the high value and high level of dependence on these resources, little scientific work has focussed on quantitative assessment of the effects of human activities on these coral reefs, and the magnitudes and effects of such impacts remain largely unquantified (Bergman and Öhman 2001). Furthermore, fisheries management efforts in East African countries are hindered by a lack of accurate catch data (FAO 2005), and monitoring and assessments of coral reefs are often based on data collected on small geographic areas that are not representative of the entire region (Wilkinson 2008). The first step to assessing the status of these ecosystems is to obtain baseline data of the resources present, and their distributions (Wilkinson et al. 2003). East African Marine Transect Expedition 1 In 2012/2013, the East African Marine Transect Expedition (EAMT), a freelance research expedition, was undertaken to survey the shallow coral reef fishes and benthic communities along the East African coastline. This expedition surveyed 208 sites, from southern Mozambique to central Kenya. The expedition revealed incredible insights into the status of coral reef communities in East Africa. Five years later, the same team will undertake a follow-up expedition. This expedition will i) replicate the data collected in 2012/2013, thus providing a temporal comparison with the 2012/2013 data, and ii) include greater geographical coverage (KwaZulu-Natal in South Africa to central Kenya) and improved sampling technologies that will allow data to be collected from both shallow and deep reef ecosystems (max depth 100 m). East African Marine Transect Expedition 2: Aims and objectives Considering the poor status of the coral reef ecosystems in East Africa (Pereira et al. 2014), the number of people whom rely on these ecosystems for food or income, and the lack of relevant data throughout much of East Africa’s coastline, the EAMT 2 expedition aims to survey shallow and deep water coral reefs and coral reef fish communities, to provide a dataset that spans much of the East African coastline. The objectives are split into three phases, with different end goals, but sampling for the three phases will be conducted concurrently. The three phases, their end goals and objectives are as follows: Phase 1: Shallow water reef communities - repeat sampling of 2012/2013 expedition sites, for temporal comparison, as well as expansion of geographic coverage of sampling in shallow waters by surveying a number of new sites: 1. New/comparative dataset on shallow water (
