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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 (<25 m deep) coral reef fish communities. 2. New/comparative dataset on shallow water (<25 m deep) coral reef benthic communities. Phase 2: Deep water reef communities – sampling of new sites, in deeper waters, to provide new data on East Africa’s deeper reef areas: 3. New baseline dataset on deep water (25 – 100 m deep) coral reef fish communities. 4. New baseline dataset on deep water (25 – 100 m deep) coral reef benthic communities. 5. Exploration of the sub-photic zone (>100 m deep). Phase 3: In conjunction with Phases 1 and 2, which are aimed at quantifying fish biomass, Phase 3 seeks to assess the suitability of these fish for human consumption: 6. Quantification of microplastic assimilation and toxicity levels in commonly eaten fish in East Africa. 2
2. Field sampling Sampling design
Within each coastal region, four discrete sampling
The expedition will span more than 3 500 km of the
locations will be identified, separated by ≥ 10 km.
East African coastline, from the north east of South
Within each of the four sampling locations, shallow
Africa, through Mozambique and Tanzania to
and deepwater sampling will be conducted as follows:
northern Kenya. This area will be divided into 15 PHASE 1: Shallow sampling (< 25 m): 1. Diver-operated stereo video for fish community x 4 locations per region
coastal regions, each spanning 100 to 200 km, or 1q1q30’ of latitude. Sampling for all methods will follow a fully replicated, nested sampling design.
x
4 spatially-segregated dive sites per location
x
12 transects (25 x 10 m) per dive
x
Total = 2 880 transects across 240 dive sites
2. Benthic photographs for reef community x 4 locations per region x
4 spatially-segregated dive sites per location
x
12 transects per dive
x x
5 benthic photographs per transect Total = 14 400 shallow benthic photographs
PHASE 2: Deep water sampling (25 – 100 m): 3. Baited remote underwater video for deep water fish x
4 locations per region
x x
3 depth-segregated strata per location 3 video deployments per depth stratum
x
Total = 540 video deployments
4. Remote drop cameras for benthic reef community x
4 locations per region
x
3 depth-segregated strata per location
x x
3 drop camera transects per depth stratum 10 photographs per transect
x
Total = 5 400 deep benthic photographs
5. ROV for deep water exploration Deep water reefs in selected regions will be explored by ad hoc ROV survey dives, to identify geophysical features, rare or endangered fish species, and to photograph the benthic community. PHASE 3: Microplastics assimilation analysis: 6. Microplastics analysis x Triplicate Biological tissue samples from selected locations, from different species (to be determined).
Figure: East African Marine Transect Expedition study area and coastal regions that will be surveyed.
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3. Sampling technologies Underwater videography and photography are powerful tools for assessing marine resources. Objectives 1 through 5 (Phases 1 and 2) will be achieved using a suite of diver-based and remote underwater videography and photography technologies. Digital footage and photographs provide permanent records that can be archived (Cappo et al. 2006), analysed in a laboratory and re-analysed if necessary, for example for species identification (Harvey et al. 2001, Langlois et al. 2010). In addition, the use of video and photographic cameras in stereo allows for accurate and precise estimates of fish length and position, and sizes of census areas (Harvey and Shortis 1996, Harvey et al. 2002, Cappo et al. 2006). This provides accurate estimates of the sizes, density and biomass of fish species (Cappo et al. 2003), as well as sizes, percentage cover and size distributions of invertebrates, such as corals (Harvey and Mladenov 2001). They are also suitable for marine protected areas (MPAs) or sensitive areas due to their non-destructive nature (Mallet and Pelletier 2014).
Phase 1 Component 1 – Diver-operated stereo video transects for assessment of shallow coral reef fish communities Shallow water coral reef ecosystems fringe much of the tropical shorelines of many continents. As a result, they are easily accessible and some of the most heavily fished marine ecosystems, which has major impacts on their fish communities. Gaining information on the health, trends, threats and impacts on these ecosystems is essential to ensure their persistence. Technology SCUBA-based, diver-operated stereo video technology (stereo DOV) is a robust tool for assessing these shallow reef fish communities. Stereo DOV transects allow large areas of reef to be censused using a standardised methodology, and allow for objective, accurate estimates of numerical and gravimetric fish density (Harvey et al. 2002, Watson et al. 2005). DOV has been used extensively for assessing spatial and temporal patterns of fish abundance, size composition and species composition (Mallet and Pelletier 2014). The expedition will use stereo DOV to survey the shallow water (<25m) coral reef fish communities throughout East Africa. The stereo DOV unit consists of two high definition digital video cameras. Each camera is housed in a custom built waterproof housing, and the two housings are mounted securely to a solid aluminium frame. The housings and frame are designed to maintain calibration integrity of the system. The cameras are positioned approximately 0.7 m apart, with the housings inwardly converged at an angle of eight degrees. This enables computer software to accurately locate an object in three dimensional space. The DOV base setup includes a synchronization diode, fixed 1 m in front of the cameras, along a perpendicular bar, where it is common to the fields of view of both cameras. The diode enables the synchronisation of the two video files (i.e. stereo imagery) recorded, which is necessary for accurate estimates of fish length.
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Methodology and data analysis Diver-operated stereo video sampling will follow a fully replicated, nested sampling design. Four dives will be conducted at each of four locations, within each of 15 survey regions, for a total of 240 dives. Each sample will consist of 12 x 25-m transects, separated by 10-m buffers (transects will be pooled within each dive). Diver 1 will swim with the DOV at 0.5 m above the reef. Diver 2, attached to diver 1 by a graduated dive reel, will signal to the DOV diver the start and end of each transect. The approximate (within 10 m) location of the census area will be obtained by floating a GPS unit tethered to the reel diver. Each dive will take approximately 30 minutes.
The digital footage will be analysed in the software package EventMeasure (www.seagis.com.au). A background database is linked to the images, allowing the analyst to count, name and estimate lengths of every fish seen in the video footage. The analyst locates the tip of the snout and the caudal fork of each fish, using the cursor, on each of the left and right synchronized images, which the software then converts to fish length, and x, y and z coordinates of the position of the fish relative to the center of the cameras (i.e. the centre of the transect area). The 10-m transect width is maintained by excluding measurements obtained more than 5 m either side of the center of the cameras. Measurement accuracy is maintained by excluding measurements beyond 7 m from the cameras, where the calibration accuracy of the system is known to deteriorate (Harvey et al. 2002). Fish counted within the measured census area are then used to calculate abundance and density. Collaborations, links and data sharing x
Wildlife Conservation Society
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CORDIO (Coral Reef Degradation in the Indian Ocean, Kenya)
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University of Western Australia
Expected outcomes x
New dataset on shallow water coral reef fish communities in East Africa
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Assessment of MPA effectiveness in East Africa
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Identification of fish diversity hotspots, healthy reefs and overexploited reefs
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Comparative (time series) dataset for comparison with EAMT 1 DOV dataset to show temporal trends
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Oceanic basin-scale comparative dataset with Western Australia DOV
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A virtual medium by which East Africa’s reef community is accessible to an unlimited audience
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Component 2 – Photographic transects for assessment of shallow water benthic communities Coral reefs are directly threatened by ecological changes from overexploitation and physical damage from destructive fishing practices, such as drag nets and blast fishing (De’ath et al. 2012, Fenner 2014). These threats are exasperated by sea temperature rise and ocean acidification, which result in weaker coral skeletons, loss of coral cover and changes in species composition (Hoegh-Guldberg et al. 2007, Baker et al. 2008, Hughes et al. 2010). It is therefore essential to understand reef health and the potential threats to reefs, in order to maximise both conservation efficiency and recovery (Baker et al. 2008, Graham et al. 2008) and test the effectiveness of protection (Nadon and Stirling 2005, De’ath et al. 2012). However, there remains relatively little information on the status of coral reefs in many parts of the Indian Ocean (Ateweberhan et al. 2011). Technology High resolution photographic surveys are commonly and widely used for assessments of benthic communities, and can provide an accurate, precise, standardised and cost-effective method for determining benthic species compositions and diversity, and quantifying percentage cover of different species or functional groups (Jokiel et al. 2015). The digital imagery also provides a permanent, archived record. The sampling equipment for the benthic cover assessments will consist of a high definition photographic camera in a waterproof housing, securely mounted to a square quadrat frame. The quadrat will be 0.5 x 0.5 m, and provide a standardised census area. Using a standardised field of view in each photograph will provide a reference scale, allowing for measurement of individual organisms, and quantification of the area covered by each. This will also allow determination of the extent and quantification of the level of coral bleaching.
Methodology and data analysis Shallow water benthic communities will be surveyed and quantified using a series of high-definition photographs from each transect, taken during the dives for the DOV sampling. A third diver will accompany the DOV divers, swimming between them along the centre of the transect area. Within each 25-m transect, the diver will take at least 5 photographs, at random intervals. This will be done by gently lowering the camera and frame toward the reef, and positioning the camera perpendicular to the reef surface, without damaging the benthic cover. The diver will ensure that each photograph is suitably in focus. Completing this on each transect will give 60 benthic photographs per dive. This will be conducted on each of the 240 dive sites, which will provide in total 14 400 high definition images of the substrate.
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Photographs will be analysed using the software CPCe (Coral Point Count with Excel extensions, Kohler and Gill 2006). For each photograph, only the area within the quadrat frame will be analysed. During digital processing, a grid will be overlaid onto each image, and 50 points marked using a random stratification process. The taxon of the organism (or the substrate type) underlying each point will then be identified to Genus level (or species level where possible). Each organism in the frame can also be measured, and its surface area calculated, using the functionality within the CPCe software. The area (proportion of quadrat) occupied by each taxon can then be calculated, to provide data on the geographic distributions, size compositions and relative coverage compositions of each taxon, and benthic community composition in each region. Screenshot of CPCe software, showing points randomly overlaid onto benthic photograph (taken from Kohler and Gill 2006). Taxa represented under each point are identified, recorded and automatically saved to a spreadsheet Collaborations, links and data sharing x
CORDIO (Coral Reef Degradation in the Indian Ocean, Kenya)
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Oceanographic Research Institute (South Africa)
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Reef Check (http://www.reefcheck.org)
Expected outcomes x
New dataset on shallow water coral reef fish communities in East Africa
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Dataset to assess the impacts of sea temperature rise and ocean acidification on benthic (particularly coral) communities
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Assessment of MPAs in East Africa for the protection of the benthic (reef) community
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Identification of coral diversity hotspots, pristine reefs and highly damaged reefs
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Benthic data as a factor for explaining shallow water reef fish community observations
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Comparative dataset for comparison with EAMT 1 benthic community dataset to show temporal trends
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Geographically widespread dataset on East Africa’s corals, for comparison with previous studies
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Phase 2 Component 3 – Remote underwater video for assessments of deep water fish communities Deep water reefs in East Africa are extensive and there is evidence that the fish communities associated with these deeper reefs differ considerably from the shallow reef communities; however, these deep water reef fish communities have been the focus of little research, and much of the reef fish community below 25 m remains unexplored, albeit extensively fished (Bernard et al. 2014). While diver-operated video provides a robust technique for sampling shallow water fish and benthic communities, the method is not suitable at depths that exceed safe diving limits (>25 m). Baited remote underwater video (BRUV) provides a robust, cost-effective, standardised means for quantifying fish communities, and can be used in deep water (well beyond SCUBA limitations) (Cappo et al. 2006). BRUVs require no divers, require little manpower and multiple sites can be sampled simultaneously by a small team (Langlois et al. 2010, Harvey et al. 2012). As with stereo DOV, the use of BRUVs is non-destructive, and can be used in sensitive areas such as MPAs. BRUVs have been employed for rapid assessments, long-term monitoring and MPA assessments throughout the world (Cappo et al. 2006, Harvey et al. 2012). BRUVS are currently being used in a dedicated global assessment of reef-associated shark and ray populations (https://globalfinprint.org) and numerous southern African MPA monitoring programmes (Bernard et al. 2014); however, they have been used little in East Africa. As with the stereo DOV, stereo BRUV systems allow the accurate measurement of fish lengths, and thus provide valuable information on community structure and length-frequency compositions of the different species. Stereo BRUVS will be used in the expedition to provide quantitative data on deep water reef fish communities (25 – 100 m). Technology The construction of the stereo BRUV units includes two HD digital video cameras, in waterproof housings, mounted onto a solid stainless steel frame (cameras inwardly converge as for the DOV). The frame is weighted at the bottom and designed for minimum hydrodynamic resistance, to prevent the unit moving when deployed in strong current. The unit is connected to the surface by a rope and a float, to allow retrieval from a vessel.
Methodology and data analysis Contrary to diver based video transects, which cover large areas of reef, BRUV samples are based on stationary cameras. A bait canister is suspended along an arm, 1 m in front of the cameras. The canister is filled prior to each deployment with 800 g of bait, which acts as an attractant for fishes (Bernard and Götz 2012).
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Stereo BRUV stations will be conducted in a fully replicated, nested sampling design. Sites within each region will be randomly selected, ensuring deployment on reef substrate (which will be determined using digital benthic maps, and verified by the vessel’s echo-sounder) and stratified by depth. BRUV recordings will be made at depths from 25 to 50 m, 50 to 75 m, and 75 to 100 m. Three BRUV replicates will be conducted in each depth stratum, in each of four locations, in each of the 15 coastal regions, giving a total of 540 deployments. BRUV units will be deployed from a vessel by a winch and davit arm. A number of units will be deployed concurrently at several sites, to increase the efficiency of sampling. Each sample is based on 1 hour of footage at that site.
Video footage will be analysed in the software EventMeasure (www.seagis.com.au). As the BRUV camera setup remains stationary throughout the sample, abundance cannot be estimated in the same way as for the DOV (which records cumulatively each individual encountered in the transect census area). For the BRUV samples, the relative abundance of each species will be estimated using the MaxN approach (maximum number, Priede et al. 1994), which is based on the frame in which the maximum number of individuals of that species is recorded within the video field of view (Cappo et al. 2003). This value gives a minimum estimate of individuals, as it does not include individuals present that may have been outside of the field of view during that frame, but is the preferred method as it prevents the counting of a single individual more than once (Cappo et al. 2006). Collaborations, links and data sharing x
South African Institute for Aquatic Biodiversity/South African Environmental Observation Network
x
Oceanographic Research Institute (South Africa)
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Australian Institute for Marine Science Global FinPrint Project
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University of Western Australia
Expected outcomes x
First deep water reef fish dataset spanning much of East Africa’s coastline
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Information for assessment of East Africa’s MPAs for protection of deep water fish communities
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Exponentially increased geographical coverage of existing BRUV datasets in the East African region
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Complement to reef fish community dataset obtained during the DOV surveys (± 8 to 100 m deep)
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Complement to current research on MPAs and fishery species in southern Africa using BRUV sampling
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Complement to global BRUV dataset on sharks, collected for Global FinPrint Project 9
Component 4 – Drop camera photographic transects for assessment of deep water benthic communities Deep water reefs in many areas may cover considerably greater area than adjacent shallow coral reef. These reefs provide the necessary structure that supports important fish species and communities, and damage to or deterioration of these reefs and their benthic communities may have severe negative impacts on the species they support. However, due to the logistical complexities of surveying these deep reef habitats, they have received relatively little research attention (Shortis et al. 2008, Smale et al. 2010). There is, thus, also a lack of information on the impacts of sea temperature rise and associated bleaching on deep water benthic communities (particularly corals), and their resilience to such disturbances. Geo-referenced photographic or video images can provide fine-scale, detailed information on deep benthic communities (Shortis et al. 2008). Drop cameras (photographic or video cameras lowered from a vessel at a series of grid points or along a transect) can provide a robust, cost effective and time efficient tool for assessing benthic communities in shallow and deep water (Cole et al. 2001, Rooper and Zimmerman 2004). They have been used widely to collect quantitative data on habitat classifications and benthic cover, and have provided much information on rare species and unknown faunal-habitat associations (Shortis et al. 2008, Smale et al. 2010). Drop cameras allow for the remote sampling of the benthos, deeper than safe diving depths. Technology Drop cameras will be used at a series of points at each site, to collect photographic data on benthic communities, and obtain data particularly on coral, sponge and algal cover. The drop camera system consists of a steel frame that houses a GoPro camera. As the drop cameras are intended for deep deployments, the frame is equipped with two waterproof lights, to provide light onto the field of view, to ensure that images are in focus and of a suitable quality for taxon identification. Methodology and data analysis Drop cameras will be deployed from a vessel, equipped with a davit arm and winch for retrieval. A transect of 10 benthic photographs, taken 30 m apart, will be conducted alongshore, in association with each BRUV deployment, following the same nested design as the BRUV sampling. This will give three drop camera transects in each of the three depth strata (25 – 50 m, 50 – 75 m, 75 – 100 m), in each of the four locations, in each of the 15 survey regions. This will provide a total of 5 400 deep benthic photographs. At each station, a depth reading and GPS coordinate will be taken, to georeference each image. The camera will be set to take one photograph every 2 seconds.
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Once deployed, the system will be lowered to the substrate. The unit will be left on the substrate, stationary, for a period of 8 – 10 seconds to ensure that at least one suitable image is captured. After this, the unit will be raised roughly 5 m above the sea floor whilst the boat moves to the next drop point, and the process is repeated until the transect is complete. The photographs will be analysed in the same way as the diver-captured benthic photographs, using CPCe software, with a set of grid points overlaid onto each image, and the taxon underlying each point identified.
Collaborations, links and data sharing x
CORDIO (Coral Reef Degradation in the Indian Ocean, Kenya)
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Oceanographic Research Institute (South Africa)
Expected outcomes x
First deep water coral reef benthic community dataset spanning much of East Africa’s coastline
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Information on latitudinal and depth gradient distributions of corals, sponges and other benthic species
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Information for assessment of East Africa’s MPAs for protection of deep water coral communities
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Benthic reef data as a factor for comparison with deep water reef fish community data
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Complement to benthic reef community data obtained during the shallow-water photographic transects, to provide a comprehensive benthic community assessment from ± 8 to 100 m deep
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Component 5 – Remotely operated vehicle for exploration of deepwater environments The advent of remotely operated vehicles (ROVs) has vastly increased the depth capabilities of marine research and exploration, allowing scientists to explore new depths, new communities and new ecosystems, that were previously out of reach (Bachmayer et al. 1998, Angeletti et al. 2010). ROVs have been responsible for numerous discoveries, such as historical shipwrecks, and new coral and fish species (Giusti et al. 2012), and allowed researchers to gain valuable information on rare species such as the coelacanth. A number of studies have even utilised ROV-based video techniques to determine fish density, size and community composition (Patterson et al. 2008, Andalora et al. 2012). However, to date, very little information exists on the deepwater communities of East Africa, and little ROV work has been done in this region. Technology The proposed ROV for the expedition is the Seaeye Falcon. This ROV is designed to dive to a maximum depth of 300 m. The onboard video links directly to a surface monitor, providing the ROV pilot with a realtime visual of where the ROV is heading, and the underwater environment which the ROV is surveying. The ROV has onboard videography and photography capabilities, allowing the capture of images and video footage of animals or the benthos. The ROV is equipped with powerful lights, to provide light and thus visibility in the deepwater environment. Methodology The expedition will provide an opportunity to explore the deepwater reef ecosystems of East Africa by ROV. This will be an exciting component of the expedition, as exploration, particularly deepwater exploration by ROV, constantly reveals new data, new information, new distributions, and even new species. The expedition will make use of diver-operated stereo video and benthic photographs to survey the shallow (< 25 m deep) reef fish communities, and baited remote underwater video and drop camera photographs to sample deep communities (25 m to 100 m), i.e. within the photic zone, within which sunlight penetrates. The ROV will allow sampling into deeper water, to provide insights into and photographs and video footage of the deeper reef habitats and organisms, beyond 100 m and thus in the sub-photic zone (deeper than sunlight penetrates). The ROV will be deployed at selected sites, to explore the deep East African reefs, in search of endangered species, rare species and important ecological phenomena such as spawning aggregations and deep water corals.
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The Seaeye Falcon in operation underwater. The video and stills cameras provide the opportunity to record and capture footage and photographs of marine organisms, while the lights allow the ROV to “see” in deep water, beyond the photic zone where light does not penetrate. Photo courtesy of ROV pilot Ryan Palmer
Furthermore, recent fisheries compliance expeditions have revealed that Tanzania is a hotspot for blast fishing. But what effect is blast fishing having in deep water? Similarly, what effect is overexploitation having on threatened and endangered species on deep reefs? The expedition will thus use the ROV to help to determine how deep the impacts of blast fishing extend, and whether deep water reefs offer a refuge for threatened species. Collaborations, links and data sharing x
South African Institute for Aquatic Biodiversity
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South African National Biodiversity Institute
Expected outcomes x
Novel data on East Africa’s deep benthic communities and fish communities
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Exploratory research for rare or endangered species (distributions)
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Exploratory observations to identify aggregations of fish or invertebrates
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Assessment of whether East Africa’s MPAs provide refuges for old, mature fish or endangered species
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Identification of dynamite scars to determine depth range of blast fishing (focus on Tanzania)
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Phase 3 Component 6 – Quantifying microplastics assimilation within commonly eaten fishes in East Africa Quantifying ingestion and assimilation rates of microplastics in marine food webs presents fascinating analytical and ecological questions. Analytical approaches to date have focused on direct detection of microplastics in gastrointestinal tracts or tissue (Vandermeersch et al. 2015, Duis and Coors 2016), biomarkers analysis (Fossi et al. 2015), or inferences drawn from concentrations in seawater (Bouwmeester et al. 2015). These approaches have been valuable in establishing that microplastics are ingested but they do little to contribute to our understanding of overall ingestion and assimilation rates. This gap in our understanding leaves us with an incomplete understanding of the physiological and ecological impacts of microplastics. One potential solution to this problem is to integrate conventional gut and inferential measures with stable isotope analyses (SIA) that rely on the unique chemical signature of various assimilates to determine the relative impact of alternative food sources. This approach has been widely used in ecology and forensics but to our knowledge this would be the first time it has been used to assess the impacts of microplastic pollution. Microplastics assimilation and ingestion analysis Boecklen et al. (2011) reviewed the progress and opportunities to use SIA in trophic ecology and showed how the refinement of isotope mixing models, physiological incorporation models, and compound specific isotopic analysis have lead to an exponential increase in the use of this method to understand ecological processes. Fundamentally, SIA requires distinctive isotope signatures for the various materials ingested. This requires variation in the
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C/12C,
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O/16O, or
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N/14N between the natural and anthropogenic materials in the diet.
Fortunately, the chemical synthesis process for plastics provides microplastics with an isotopic signature that is chemically distinct from planktonic sources. A leading SIA instrument producer has recently developed a protocol for distinguishing between corn-based plastics, with a C isotopic value of -11‰, and fossil fuel derived plastics which have a C isotopic value of -30‰. In marine systems, distinguishing between natural C sources and fossil fuel derived sources should be even easier, as phytoplankton has a C isotopic value of ca. -5‰. Methodology Understanding the assimilation of microplastics into tissues of commonly eaten fishes along the East African coastline will provide valuable evidence regarding possible plastic contamination in fish, which in turn will indicate possible health threats to the current coastal population of East Africa. For isotopic analysis, fin clip samples will be taken from fish found in local fish markets, from across the sampling area. Samples will be collected from at least three individuals, at several localities, from at least five of the most common, broadly distributed species that are often consumed by humans. Fin clips will be dried or frozen, and then transported to Utah for analysis at the SIRFER laboratory (Stable Isotope Ratio Facility for Environmental Research). Collaborative links, data analysis and sharing x
SIRFER lab, Stable Isotope Ratio Facility for Environmental Research, Brigham Young University
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Associate Professor, John S.K. Kauwe
Expected outcomes: x
Microplastic contamination levels in commonly eaten marine fishes in East Africa
x
Geographical representation of fish with microplastic contamination 14
4. Expected outcomes There will be a host of scientific and ecological outcomes from the expedition: Scientific outcomes x
The data collected during the expedition will be made openly accessible.
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New high-definition stereo DOV datasets on shallow water coral reef fishes of a major portion of the East African coastline
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New dataset of high-definition photographs of the shallow water benthic communities of a major portion of the East African coastline
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Datasets for temporal comparison with EAMT 1, a previous expedition
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New dataset from the BRUV deployments, on deep water reef fish communities
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East African compliment to the Global Finprint Project global shark datasets
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Extension of BRUV data for MPA assessments from South Africa and southern Mozambique
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New dataset on the deep benthic reef communities
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New data on fish microplastics assimilation
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Updated information on fish and invertebrate species distributions in the East African region
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Exploratory data and possible new distribution data for rare and endangered species from ROV dives
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New data regarding the geographical identification of microplastic polluted areas
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Multiple collaborations and increased data sharing at local and international levels
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Numerous scientific publications, student projects, popular articles and conference presentations
Social/institutional outcomes 1. Research: Raw and processed data will be made available to researchers or research institutions that wish to utilise the dataset, or parts thereof, for comparative research, or for further analyses that may lead to improved management or conservation. 2. Management: The results of the analyses and recommendations for improved management or conservation will be made available to the relevant management authorities in each region. The results and their consequences will be interpreted in terms of the management requirements in each area, from which informed decisions can be made, and strategic plans formulated for improved management. It is also hoped that the results will highlight and provide empirical evidence that MPAs are providing effective protection for coral reef fishes, and the potential for seeding of adjacent unprotected areas, hopefully thereby improving local fishers’ attitudes towards, and support for, MPAs. 3. Education: The results will be available to tertiary academic institutions in the study region that wish to utilise the data for the training or teaching of students, and for the advancement of marine ecological knowledge at the tertiary level. The processed data and results will also be made available to primary and secondary educational institutions and, where possible, localised results and the overall goals and rationale of the expedition will be presented to local educational institutions during the expedition, to forge improved understanding of the value of marine resources, and the need for conservation thereof.
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5. Literature cited Andalora F, Ferraro M, Mostarda E, Romeo T, Consoli P (2012) Assessing the suitability of a remotely operated vehicle (ROV) to study the fish community associated with offshore gas platforms in the Ionian Sea: a comparative analysis with underwater visual censuses (UVCs). Helgoland Marine Research 66(3): DOI 10.1007/s10152-012-0319-y Angeletti L, A Ceregato, Ghirelli M, Robomar S, Gualandi B, Lipparini E, Malatesta D, Sperotti A, Taviani M (2010) ROVSCUBA integrated survey of the Montecristo Island Nature Reserve (Tuscan Archipelago National Park, Mediterranean Sea). International Journal of the Society for Underwater Technology 29(3): 151-154. doi:10.3723/ut.29.151 Ateweberhan M, McClanahan T R, Graham NAJ, Sheppard (2011) Episodic heterogeneous decline and recovery of coral cover in the Indian Ocean. Coral Reefs 30:739. doi.org/10.1007/s00338-011-0775-x Bachmayer R, Humphris S, Fornari D, Van Dover C, Howland J, Bowen A, Elder R, Crook T, Gleason D, Sellers W, Lerner S (1998) Oceanographic Research Using Remotely Operated Underwater Robotic Vehicles: Exploration of Hydrothermal Vent Sites On The Mid-Atlantic Ridge At 37°North 32°West. Marine Technology Society Journal 32(3): 37-47 Baker AC, Glyn PW, Riegl B (2008) Climate change and coral reef bleaching: An ecological assessment of long-term impacts, recovery trends and future outlook, Estuarine, Coastal and Shelf Science 80(4): 435-471. doi:10.1016/j.ecss.2008.09.003 Bergman KC, Öhman MC (2001) Coral reef structure at Zanzibar Island, In: Richmond M, Francis J (eds) Marine Science Development in Tanzania and Eastern Africa Proc 20th Ann Conf Adv Mar Sci Tanzania: 263-275 Bernard ATF, Götz A (2012) Bait increases the precision in count data from remote underwater video for most subtidal reef fish in the warm-temperate Agulhas bioregion. Marine Ecology Progress Series 471: 235-252 Bernard ATF, Götz A, Parker D, Heyns ER, Halse SJ, Riddin NA (2014) New possibilities for research on reef fish across the continental shelf of South Africa. South African Journal of Science 110(9/10): Art. #a0079, 5 pages. http://dx.doi.org/10.1590/sajs.2014/ a0079 Boecklen WJ, Yarnes CT, Cook BA, James AC (2011) On the Use of Stable Isotopes in Trophic Ecology. In D J Futuyma, H B Shaffer, and D Simberloff, editors. Annual Review of Ecology, Evolution, and Systematics, Vol 42. Annual Reviews, Palo Alto: 411-440 Bouwmeester H, Hollman PCH, Peters RJB (2015) Potential Health Impact of Environmentally Released Micro- and Nanoplastics in the Human Food Production Chain: Experiences from Nanotoxicology. Environmental Science and Technology 49:8932-8947 Cappo M, Harvey E, Malcolm H, Speare P (2003) Potential of video techniques to monitor diversity, abundance and size of fish in studies of Marine Protected Areas. pp. 455-464. In: Beumer JP, Grant A and Smith DC Aquatic Protected Areas what works best and how do we know? World Congress on Aquatic Protected Areas proceedings, Cairns, Australia, August 2002. Australian Society of Fish Biology Cappo M, Harvey E, Shortis M (2006) Counting and measuring fish with baited video techniques – an overview. pp. 101 – 104. In: Lyle, J.M., Furlani, D.M., & Buxton, C.D. (Eds.). 2007. Cutting-edge technologies in fish and fisheries science. Australian Society for Fish Biology Workshop Proceedings, Hobart, Tasmania, August 2006, Australian Society for Fish Biology. Carpenter KE, Abrar M, Aeby G, Aronson RB, Banks S, Bruckner A, Chiriboga A, Cortés J, Delbeek J, DeVantier L, Edgar G, Edwards AJ, Fenner D, Guzmán HM, Hoeksema BW, Hodgson G, Johan O, Licuanan WY, Livingstone SR, Lovell ER, Moore JA, Obura DO, Ochavillo D, Polidoro BA, Precht WF, Quibilan MC, Reboton C, Richards ZT, Rogers AD, Sanciangco J, Sheppard A, Sheppard C, Smith J, Stuart S, Turak E, Veron JEN, Wallace C, Weil E, Wood E, Elizabeth (2008) One-Third of Reef-Building Corals Face Elevated Extinction Risk from Climate Change and Local Impacts. Science 321(5888): 560563 Cesar HSJ (2000) Coral Reefs: Their Functions, Threats and Economic Value. In: Cesar HSJ (ed.) Collected Essays on the Economics of Coral Reefs. CORDIO, Kalmar University, Sweden: 14-39 Cole R, McComb P, Sait J (2001) Use of Drop Video to Map Habitats in a High Energy Shallow Reef Environment. Pp. 74 – 80. In: Harvey ES and M Cappo (2001). Direct sensing of the size frequency and abundance of target and nontarget fauna in Australian Fisheries - a national workshop. 4-7 September 2000, Rottnest Island, Western Australia. Fisheries Research Development Corporation. 187 pp, ISBN 1 74052 057 2.
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De’ath G, Fabricius KB, Sweatman H, Poutinen J (2012) The 27–year decline of coral cover on the Great Barrier Reef and its causes. Proceedings of the National Academy of Sciences 109(44): 1795-1799 Done TJ, Ogden JC, Weibe WJ, Rosen BR (1996) Biodiversity and Ecosystem Function of Coral Reefs. In: Mooney HA, Cushman JH, Medina E, Sala OE, Schulze ED (eds). Functional Roles of Biodiversity: A Global Perspective. John Wiley & Sons Ltd, United Kingdom: 493 pp Donner S, Skirving WK, Little CM, Oppenheimer M, Hoegh-Guldberg O (2005). Global Change Biology 11: 2251-2265 Duis, K, Coors A (2016) Microplastics in the aquatic and terrestrial environment. Environmental Sciences Europe 28:1-25 FAO (2005) Review of the state of world marine fishery resources. FAO Fisheries Technical Paper 457. Food and Agriculture Organization of the United Nations, Rome Fenner D (2014) Fishing down the largest coral reef fish species. Marine Pollution Bulletin 84: 9-16 Fossi, M. C., L. Marsili, M. Baini, M. Gianne , D. Coppola, C. Guerran , I. Caliani, R. Minutoli, G. Lauriano, M. G. Finoia, F. Rubegni, S. Panigada, M. Berube, J. U. Ramírez, and C. Panti. 2015. Fin whales and microplastics: The Mediterranean Sea and the Sea of Cortez scenarios. Environmental Pollution 209:68-78. Giusti M, Bo M, Bavastrello G, Angiolillo M, Salvati E, Canese S (2012) Record of Viminella flagellum (Alcyonacea: Ellisellidae) in Italian waters (Mediterranean Sea). Marine Biodiversity Records 5(e34): 1-5 Graham NAJ, McClanahan TR, MacNeil MA, Wilson SK, Polunin NVC, Jennings S, Chabanet P, Clark S, Spalding MD, Letourneur Y, Bigot L, Galzin R, Öhman MC, Garpe KC, Edwards AD, Sheppard CRC (2008) Climate Warming, Marine Protected Areas and the Ocean-Scale Integrity of Coral Reef Ecosystems. PLoS ONE 3(8): e3039. doi:10.1371/journal.pone.0003039 Harvey E, Fletcher D, Shortis M (2001) A comparison of the precision and accuracy of estimates of reef-fish lengths determined visually by divers with estimates produced by a stereo-video system. Fishery Bulletin 99: 63-71 Harvey E, Fletcher D, Shortis M (2002) Estimation of reef fish lengths by divers and by stereo-video. A first comparison of the accuracy and precision in the field on living fish under operational conditions. Fisheries Research 57: 255-265 Harvey E, Mladenov P (2001) The Uses of Underwater Television and Video Technology in Fisheries Science: A Review. pp. 90 – 107. In: Harvey ES and M Cappo (2001). Direct sensing of the size frequency and abundance of target and nontarget fauna in Australian Fisheries - a national workshop. 4-7 September 2000, Rottnest Island, Western Australia. Fisheries Research Development Corporation. 187 pp, ISBN 1 74052 057 2. Harvey ES, Newman SJ, McLEan DL, Cappo M, Meeuwig JJ, Skepper CL (2012) Comparison of the relative efficiencies of stereo-BRUVs and traps for sampling tropical continental shelf demersal fishes. Fisheries Research 125-126: 108-120. doi:10.1016/j.fishres.2012.01.026 Harvey ES, Shortis M (1996) A system for stereo-video measurement of subtidal organisms. Marine Technology Society Journal 29: 10-22 Hodgson G (1999) A global assessment of human effects on coral reefs. Marine Pollution Bulletin 38(5): 345-355 Hoegh-Guldberh O, Mumby PJ, Hooten AJ, Steneck RS, Greenfield P, Gomez E, Harvell CD, Sale PF, Edwards AJ, Caldeira K, Knowlton N, Eakin CM, Iglesias-Prieto R, Muthiga N, Bradbury RH, Dubi A, Hatziolos ME (2007) Coral Reefs Under Rapid Climate Change and Ocean Acidification. Science 318: 1737-1742 Hughes TP, Graham NAJ, Jackson JBC, Mumby PJ, Steneck RS (2010) Rising to the challenge of sustaining coral reef resilience. Trends in Ecology and Evolution 25(11): 619-680 Jokiel PL, Rogers KS, Brown EK, Kenyon JC, Aeby G, Smith WR, Farrell F (2015) Comparison of methods used to estimate coral cover in the Hawaiian Islands. PeerJ 3:e954; DOI 10.7717/peerj.954 Kohler KE, Gill SM (2006) Coral Point Count with Excel extensions (CPCe): A Visual Basic program for the determination of coral and substrate coverage using random point count methodology. Computers and Geosciences 32: 1259-1269 Langlois TJ, Harvey ES, Fitzpatrick B, Meeuwig JJ, Shedrawi G, Watson DL (2010) Cost-efficient sampling of fish assemblages: comparison of baited video stations and diver video transects. Aquatic Biology 9: 155-168 Lindén O, Souter D, Wilhelmsson D, Obura D (2002) Coral Reef Degradation in the Indian Ocean. Status report 2002. CORDIO, Sweden: 276 pp Mallet D, Pelletier D (2014) Underwater video techniques for observing coastal marine biodiversity: A review of sixty years of publications (1952–2012). Fisheries Research 154: 44-62 Moberg F, Folke C (1999) Ecological goods and services of coral reef ecosystems. Ecological Economics 29: 215-233
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Muthiga N, Bigot L, Nilsson A (2008) EAST AFRICA: Coral reef programs of eastern African and Western Indian Ocean. In: Wilkinson C (2008) Status of coral reefs of the world: 2008. Global Coral Reef Monitoring Network and Reef and Rainforest Research Centre, Townsville, Australia: 296 pp Nadon M-O, Stirling G (2005) Field and simulation analyses of visual methods for sampling coral cover. Coral Reefs 2005; DOI 10.1007/s00338-005-0074-5 Obura DO, Grimsdith G (2009) Resilience Assessment of coral reefs – Assessment protocol for coral reefs, focusing on coral bleaching and thermal stress. IUCN working group on Climate Change and Coral Reefs. IUCN, Gland, Switzerland. 70 pages. Patterson WF, Dance MA, Addis DT (2008) Development of a Remotely Operated Vehicle Based Methodology to Estimate st Fish Community Structure at Artificial Reef Sites in the Northern Gulf of Mexico. Proceedings of the 61 Gulf and Caribbean Fisheries Institute, November 10 - 14, 2008, Gosier, Guadeloupe, French West Indies. pp. 263-270 Pereira MAM, Litulo C, Santos R, Leal M, Fernandes RS, Tibiriçá Y, Williams J, Atanassov B, Carreira F, Massingue A, da Silva IM (2014) Mozambique marine ecosystems review. Final report submitted to Fondation Ensemble. 139pp, Maputo, Biodinâmica/CTV Priede IG, Bagley PM, Smith A, Creasey S, Merrett NR (1994) Scavenging deep demersal fishes of the Porcupine Seabight, North-East Atlantic: observations by baited camera, trap and trawl. Journal of the Marine Biological Association of the United Kingdom 74: 481-498 Rooper C, Zimmerman M (2005) Using video to map distribution of habitat and fish in Alaska. pp. 2-3. In: Somerton DA, Glendhill CT (eds) (2005) Report of the National Marine Fisheries Service Workshop on underwater video analysis. U.S. Dep. Commerce, NOAA Tech. Memo. NMFS-F/SPO-68, 69 pp Shortis MR, Seager JW, Williams A, Barker BA, Sherlock M (2008) Using stereo-video for deep water benthic habitat surveys. Marine Technology Society Journal 42(4): 28-37 Smale DA, Kendrick GA, Waddington KI, Van Niel KP, Meeuwig JJ, Harvey ES (2010) Benthic assemblage composition on subtidal reefs along a latitudinal gradient in Western Australia. Estuarine, Coastal and Shelf Science 86: 83-92 Souter DW, Lindén O (2000) The health and future of coral reef systems. Ocean and Coastal Management 43: 657-688 UNEP (1992) Implications of Expected Climate Change in the East African Coastal Region: An Overview. Regional Seas Reports and Studies No.149, A.L Alusa and L.J.Ogallo. UNEP, Nairobi, Kenya UNEP/IUCN (1988) Coral reefs of the world. vol. 2: Indian Ocean, Red Sea and Gulf. UNEP Regional Seas Directories and Bibliographies. IUCN, Gland, Switzerland and Cambridge, United Kingdom. UNEP, Nairobi, Kenya: 389pp. Vandermeersch G, Van Cauwenberghe L, Janssen CR, Marques A, Granby K, Fait G, Kotterman MJJ, Diogène J, Bekaert K, Robbens J, Devriese L (2015) A critical view on microplastic quantification in aquatic organisms. Environmental Research 143:46-55 Wagner GM (2004) Coral reefs and their management in Tanzania. Western Indian Ocean Journal of Marine Science 3(2): 227-243 Watson DL, Harvey ES, Anderson MJ, Kendrick GA (2005) A comparison of temperate reef fish assemblages recorded by three underwater stereo-video techniques. Marine Biology 148: 415-425 Wilkinson C (2008) Status of coral reefs of the world: 2008. Global Coral Reef Monitoring Network and Reef and Rainforest Research Centre, Townsville, Australia: 296 pp Wilkinson C, Green A, Almany J, Dionne S (2003) Monitoring coral reef marine protected areas. Version 1. A practical guide on how monitoring can support effective management of MPAs. Australian Institute of Marine Science: 68 pp
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