Claire is developing highly sensitive molecular (genetic) tools to help her detect the presence of five rare ‘rhino rays’ (sawfish, wedgefish and giant guitarfish) in West Africa. She wants to use these tools to find two sawfish, two wedgefish and one giant guitarfish species in Guinea-Bissau, Mauritania and Senegal and collect information about their distribution along the coast. With few confirmed records of rhino rays in this region but anecdotal evidence that there are declining populations there, Claire’s mission is to ensure that there is enough information to develop conservation and management plans for these Critically Endangered rays.
Having grown up in Malta, a tiny island in the middle of the Mediterranean, my heart is never far from the sea. I have been passionate about exploring other cultures for as long as I can remember, and have always sought opportunities to live, study and work somewhere new. Although I learnt to dive in Malta, it was while working as a scientific volunteer for Blue Ventures Madagascar that I met my first coral reef. I found the process of systematically collecting data for research purposes absolutely thrilling. Blue Ventures works very closely with the local fishing...
Our key objective is to improve the conservation of five imperilled rhino rays in West Africa by developing new molecular tools sensitive enough to detect these exceptionally rare species and collecting valuable data on their current distributions through surveys in Guinea-Bissau, Mauritania and Senegal.
Very few recent records exist for sawfish, wedgefish and giant guitarfish in West Africa, but anecdotal evidence suggests severe declines in their populations. Knowing where a species occurs, how it uses its habitat and how its populations are changing over time is often a prerequisite for effective conservation management. Greater understanding of the extent to which these species persist in Guinea-Bissau, Mauritania and Senegal, and the identification of any priority areas, could serve as a catalyst for conservation action.
Rhino rays are a group of bottom-dwelling shark-like rays that include sawfish, wedgefish and giant guitarfish. Out of the 21 assessed species in these three families, 18 are listed as Critically Endangered on the International Union for Conservation of Nature’s Red List of Threatened Species and a further two are listed as Endangered. There are several reasons for the increased vulnerability of this group. Firstly, rhino rays tend to inhabit the shallow coastal waters of the tropics, habitat that is prone to being degraded by human activities. Secondly, many rhino rays grow slowly, are late to mature and produce few offspring. And thirdly, these species are targeted by fishers for their meat for local consumption and their high quality ‘white’ fins that fetch a very high price. Because of their long, toothed rostrum, sawfish are unusually prone to getting entangled in fishing nets. Five species of sawfish, wedgefish and giant guitarfish have been present in West Africa in the past. However, their continued presence in this region is unclear, as very few recent records exist for these species, making it likely that severe population declines, or even local extinctions, have occurred. Traditional survey methods (like gill-netting) are generally ineffective, time-consuming and costly for exceptionally rare threatened species, since the animals occur in such low numbers. Using DNA collected from environmental water samples, a technique called ‘eDNA’, has two advantages: you do not need to locate or handle the target organism, and it can detect minute traces of DNA present in the sea water.
Outside the USA, The Bahamas is the only place where Critically Endangered smalltooth sawfish can reliably be found. Tristan wants to ensure that protection measures in The Bahamas are understood and enforced as far as sawfish are concerned to close the current gap between policy and the people. He’ll be using aerial surveys, sonar and BRUVs, combined with interviews that draw on local knowledge, to identify essential sawfish habitats that need protection. Engaging with the community through workshops and by training students and meeting with government, Tristan intends to advocate for smalltooth sawfish protection throughout The Bahamas’ territorial waters.
Steven and Kevin are using genetic techniques to understand how Caribbean reef shark populations are connected across the extent of their range. Populations of this Endangered shark are in decline generally, but where they are managed and there is effective protection, their numbers are stable. With the integration of the correct information, Steven and Kevin are convinced that we can give Caribbean reef sharks a better shot at recovery and population stabilisation. They will also explore any barriers to connectivity, looking to the future recruitment and recovery of these sharks.
With very little information available about Endangered sicklefin devil rays, their seasonal aggregations at sea mounts in the Azores give Sophie an opportunity to learn more about their lives. She will be collecting satellite-tracking data that show how they move in the Azores’ exclusive economic zone. The information she collects will be used to develop maps of how the rays are using the zone and to identify essential areas that multiple species use. With this information at hand, Sophie hopes her work can contribute to a network of marine protected areas.