American Elasmobranch Society meets in New Orleans

The American Elasmobranch Society recently met in New Orleans for their annual meeting, attended by an international collective of shark and ray scientists to discuss current and ongoing work in this very eclectic field. The Cape Eleuthera Institute was represented by Oliver Shipley and Dr. Owen O’Shea of the Shark Research and Conservation Program, both giving oral presentations to a wide range of scientists from all over the world. Oliver’s presentation focused on novel methods for post-capture release of a small bodied deep-sea shark – the Cuban dogfish – and how novel approaches may increase survivorship during by-catch events. Owen spoke of the recently ‘re-discovered’ Caribbean whiptail stingray and discussed its contemporary distribution in The Bahamas and implications for management.

Dr, Owen O'Shea during his presentation on Caribbean whiptail stingrays
Dr. Owen O’Shea during his presentation on Caribbean whiptail stingrays

The week spent in New Orleans was a huge success, with the convening of several meetings and discussions pertaining to the global fin print project and a whole day dedicated to a global sawfish research symposium. Among some of the other stand out talks were the very first satellite tracking of manta rays conducted in Sudan, juvenile white shark movement in California and challenges for management of large ranging sharks, such as the great hammerhead and oceanic whitetip. It was a fantastic week with many old relationships rejuvenated, and the fostering of new ones cemented, with collaborative studies already having been discussed.

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Operation Wallacea

During the course of a six-week program, three students representing Operation Wallacea (Marcus Griffiths of the University of Nottingham, Rob McCalman of the University of Portsmouth and Lucy Arrowsmith of the University of Cardiff) have teamed up with Dr. Owen O’Shea at The Cape Eleuthera Institute to investigate the benthic habitat diversity of various creek systems around Eleuthera, The Bahamas. This project aims to establish the relationships between environmental and physical characteristics of the recently ‘re-discovered’ Caribbean Whiptail Stingray, Himantura schmardae.  As a meso-predatory species, these stingrays provide an important link between apex predators and the benthic organisms they prey upon. An abundance of this species within creek systems provides a good indication of ecosystem health.

The Ray team surveying Deep Creek - A very large and biologcally rich ecosystem bordering the deep Exuma Sound
The Ray team surveying Deep Creek – A very large and biologcally rich ecosystem bordering the deep Exuma Sound

The team are currently in the process of completing benthic habitat analysis on four sites: Deep and Wemyss Bight Creek (Atlantic/Exuma Sound) and Kemps and Starved Creek (Grand Bahama Bank). This project is collecting data using a 1m2 quadrat to assess the percentage cover of flora and fauna species found in these locations, so far completing a total of 274 quadrats over a 2.6Km2 combined study area. In addition, sediment cores; sediment depth; water salinity; dissolved oxygen and water temperature are being collected at each location to gather a broader insight into the habitual preference of juvenile Himantura schmardae that appear to be utilizing these creeks on a long term basis.

The Caribbean whiptail stingray - specimen from Deep Creek
The Caribbean whiptail stingray – specimen from Deep Creek

The aim of the investigation is to determine the relationship between the creek environments and the presence or absence of this relatively elusive stingray. Additionally the morphological, sexual and feeding characteristics will provide insight into the potential role of these marine systems as possible nursery sites. As a relatively new re-discovery for The Bahamas, this research could provide critical information towards development of successful conservation plans, and fine-tuning the coverage of marine protection areas (MPAs) as declared by The Caribbean challenge for the Bahamas in 2008.

Kemps Creek on the Banks side - a smaller, mangrove fringed creek
Kemps Creek on the Banks side – a smaller, mangrove fringed creek
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CEI scientists present research at the 13th International Coral Reef Symposium

written by Dr. Jocelyn Curtis-Quick

The International Coral Reef Symposium (ICRS) is the olympics of marine biology and is only held every four years. It is the primary international meeting focused on coral reef science and management. The 13th symposium was the biggest yet, bringing together some 2,500 coral reef scientists, policy makers and managers from 97 different nations. This meeting is very important because it provides the international science community with a platform to:

  • Increase global knowledge and interest in coral reefs, including sustainable use and conservation strategies;
  • Showcase successful science, conservation and management efforts;
  • Develop collaborations and partnerships to increase international capacity to address coral reef issues; and
  • Increase global awareness of reef degradation and possible solutions by extensive promotion in the media.
CEI scientists Zach Zuckerman, Dr Aaron Shultz and Dr Jocelyn Curtis-Quick present their parrotfish research
CEI scientists Zach Zuckerman, Dr Aaron Shultz and Dr Jocelyn Curtis-Quick present their parrotfish research

Dr Jocelyn Curtis-Quick wrapped up her time with CEI by presenting on the lionfish feeding studies and the summary of the 5-year culling program along with a collaborative project with Zach Zuckerman and Dr Aaron Shultz on the impacts of CO2 on the grazing and metabolic rates of parrotfish.  Jocelyn was not alone – many researchers that conducted fieldwork at CEI, CEI intern alumni and ex-Island School faculty were also in attendance!

Dr Jill Harris (Island School faculty 05) recently completed her PhD in marine biology at Scripps Institution of Oceanography, where she was happy to keep running into Island School student and faculty alums. Now she works for the World Wildlife Fund in Washington, DC, studying how to make MPAs more effective and presented on this work at the symposium. Jill’s job is mostly about scuba diving and statistics, just like at The Island School!

ICRS was attended by a number of the Island School community. Dr Curtis-Quick met Island School faculty alums Jill Harris and Kim Falinski along with numerous CEI visiting researchers and CEI intern alum Jason Selwyn.
ICRS was attended by a number of the Island School community. Dr Curtis-Quick met Island School faculty alums Jill Harris and Kim Falinski along with numerous CEI visiting researchers and CEI intern alum Jason Selwyn.

Dr Kim Falinski (Island School faculty 06) began an MSc in Agricultural Engineering at Cornell University, specializing in recirculating aquaculture systems after leaving The Island School.  Kim’s thesis brought her to Waimanalo, HI, to work at Oceanic Institute on scaling up microalgae production for copepod feed.  Kim then worked as a professor at the local community college before starting her PhD at the University of Hawaii at Manoa. Kim’s specialty is land based source pollutants – sediments from poor land management practices and nutrients from wastewater and inorganic fertilizers.  Today Kim works at The Nature Conservancy in Honolulu as a water quality scientist on the Marine team, which she presented on at ICRS. In her free time free time, Kim races big sail boats and run triathlons. “The Island School most certainly sent me on this path” says Kim.

The symposium covered an array of topics including coral reefs and climate change, cutting edge technology in coral science, community-based management, coastal pollution and the role of Marine Protected Areas. The main goal of the symposium wasbridging science to policy to inform and increase the effectiveness ofcoral reef conservation worldwide.  The week was huge success – we all look forward to the next meeting in 4 years’ time.

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The Bahamas National Trust Co-hosts Caribbean Shark Conservation Symposium

The Bahamas National Trust (BNT) joined the Government of St. Maarten, St. Maarten Nature Foundation, and The Pew Charitable Trusts as hosts of the Caribbean Shark Conservation Symposium, which took place from Tuesday, June 13 through Thursday, June 16.  The gathering of Caribbean island government officials, environmental NGOs, and global shark conservation experts was coordinated to discuss the future of shark conservation in the region.

As the first Caribbean country to establish a shark sanctuary and a leader in the region, the voice of the The Bahamas was represented at the meeting by Eric Carey, Executive Director of BMT.

Caribbean Reef Sharks - photo by Jim Abernethy
Caribbean Reef Sharks – photo by Jim Abernethy

Carey said: “The Bahamas National Trust has been promoting shark conservation for many years. Our efforts to secure the longline ban nearly 30 years ago, presented an incredible opportunity to protect intact shark populations. Our being asked to cohost this meeting is a clear indication that the actions taken by The Bahamas to protect our sharks, has distinguished us as a leader in ocean conservation in the Caribbean. BNT is proud to have played a part in this.”

Also in attendance was Virgin Group Founder Sir Richard Branson, who has been supportive of establishing regional shark protections throughout the Caribbean, and cohosted a similar meeting in Bimini, The Bahamas in 2015.

During the meeting, four Caribbean governments committed to help reverse this trend by fully protecting sharks in their waters. St. Maarten and the Cayman Islands announced that their economic zones (EEZs) are completely closed to commercial shark fishing.   Additionally, Curacao announced that they will establish legislation this year that will protect sharks in their waters, and Grenada is considering measures that would safeguard sharks within the country’s EEZ. Together, the two new sanctuaries cover a total of 119,631 square kilometers and raise the total number of Caribbean sanctuaries to seven.

The findings of a study of the economic impact of sharks on The Bahamas’ tourism industry were also released at the meeting. Lead investigator, Dr. Edward Brooks from the Cape Eleuthera Institute, was in attendance to discuss the study, which found that sharks generate US$113 million annually in direct expenditure and value added through tourism to the Bahamian economy.

Lemon Shark - photo by Jim Abernethy
Lemon Shark – photo by Jim Abernethy

Brooks said: “The results of our study illustrate the importance of the ongoing stewardship of sharks and rays demonstrated by The Bahamian Government over the last 25 years, for which they are now reaping the economic rewards.  However, despite the actions of The Bahamas and the other Caribbean nations who protect sharks within their waters, more work is needed on a regional basis in order to effectively manage many of these economically important species which call the entire North West Atlantic and Caribbean home.”

Sharks play a vital role in the Caribbean, both to the health of the ocean and to a countless number of people whose livelihoods are directly connected to these animals.  With at least 100 million sharks killed each year, establishing additional meaningful and lasting protections in the Caribbean will ensure a healthy shark population for future generations.

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Stingrays: Whiptail Genetics

Volunteers Dan and Stand Displaying the tow highly agile and toxic barbs from a juvenile whiptail ray from Samson Cay
Volunteers Dan and Stand Displaying the tow highly agile and toxic barbs from a juvenile whiptail ray from Samson Cay

Recently, the Cape Eleuthera Institute’s Stingray Research Group mounted its final expedition to remote cays in the Exumas Islands, to finalize the collection of genetic information from the rare, elusive and recently ‘re-discovered’ Caribbean whiptail stingray, Himantura schmardae. Led by Dr. Owen O’Shea, the team comprised of interns, Rob Hallinan and Miguel Furtado, Newcastle University Graduate Student, Dan Montgomery and Education Program leader, Stan Burnside. The aim of this particular study is to assess the genetic connectivity of this batoid across multiple spatial scales, yet restricted temporal scales. Therefore, generations of parentage and sibling relationships are examined, rather than analyzing the connectivity through an evolutionary perspective.

The smallest whiptail of the trip, seeking shelter in isolated tidal pools of Banshee Creek, Warderick Wells
The smallest whiptail of the trip, seeking shelter in isolated tidal pools of Banshee Creek, Warderick Wells

After crossing the Exuma Sound, the team first arrived at Little Creek in Guana Cay where the first whiptail stingray was located – a tiny female in shallow water as the tide ebbed. A further three more were sampled from Sampson Cay to the north, making the first day a success. The team was able to select their very own island for the night’s camping before readying the equipment for day two of three. The second day was even more successful; the team found and caught eight of these stingrays as they continued to move north. Three were found in the mangroves of Pipe Cay, two within the Compass Cay marina, and three found from a dry creek at Warderick Wells Cay. The little rays were the smallest of the project so far (228, 229 and 232 mm wide) but were also located in very small, very hot tidal pools scattered throughout a desert dry Banshee creek. Day three was more challenging as the team investigated several creeks from Shroud and Hawksbill Cays, that appeared promising, indicated by the presence of dozens of ray feeding pits. However, no whiptails were seen. With only two samples left to meet the minimum requirement for sample size, the team explored the flats of Highbourne Cay and the mouth of Ship Channel Cay where three more whiptail stingrays were sampled, and therefore bringing the total for the trip to 15, five more than our target.

Banshee Creek, Warderick Wells- there are two tiny whiptails in this tidal pool!
Banshee Creek, Warderick Wells- there are two tiny whiptails in this tidal pool!

This study is the first sine 1968 to document this species of stingray in The Bahamas, and a manuscript detailing their contemporary distribution in The Bahamas is currently under review. Now, with genetic information pertaining to 68 individuals sampled throughout the course of this study, spanning from Hummingbird Cay in the southern Exuma Cays to Hartford Creek, in the east end of south Eleuthera, Dr. O’Shea and his team can begin to analyze the relative relationships among these stingrays and determine their connectivity, along with possible migratory corridors, adding to the paucity of information not only about this species, but the habitats that support them. Interestingly, on this voyage, no mature stingrays were seen, potentially indicating a partitioning of spatial resources between juveniles and adults. Where juveniles were more often seen in shallow creek systems, larger adults tended to occupy areas of deeper water, potentially highlighting the importance of creeks as nursery grounds for juvenile Caribbean whiptail stingrays. Continuing this research this summer, Dr. O’Shea will begin to assess the significance of these shallow, warm-water creek systems on the life-history of these juvenile Caribbean whiptail stingrays.

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Lionfish Day and Jewelry Workshop with The Blue Seahorse

On Saturday, May 7th, the Reef Ecology and Restoration team at the Cape Eleuthera Institute (CEI) partnered with The Blue Seahorse gift shop in Rock Sound for a day of lionfish festivities. The afternoon was centered around different crafts and foods people can make with this invasive species. Delicious lionfish burgers were served at The Blue Seahorse and the reef team was able to demonstrate different aspects of lionfish research by teaching how to dissect and properly fillet a lionfish while handling the 18 venomous spines. A main goal of the reef team is to debunk the myth that lionfish are poisonous or deadly. The team even brought a live lionfish in a display tank to show how lionfish use their pectoral fins to herd juvenile fish for consumption.

Reef team members Helen Conlon and Pauline Navaez educate visitors about invasive lionfish, how to properly fillet them, and how their fins can be used for jewelry. Photo courtesy of The Eleutheran.
Reef team members Helen Conlon and Pauline Navaez educate visitors about invasive lionfish, how to properly fillet them, and how their fins can be used for jewelry. Artwork by Blue Seahorse owner Holly Burrows. Photo courtesy of The Eleutheran.

Along with the current threats posed by the lionfish in the Caribbean, visitors also learned about the use of the beautiful lionfish fins for jewelry. Customers were even able to purchase lionfish earrings and necklaces that artist and owner Holly Burrows made. On Thursday, May 19th, Holly came down to CEI to host a lionfish jewelry making workshop. Participants picked their fins, taken from harvested lionfish, and with the guidance of Holly created beautiful sets of earrings and necklaces. Lionfish jewelry is a fantastic way to profit from the invasion, while also helping to create a demand for lionfish–and not to mention makes for a great gift for loved ones.

Lionfish earrings made by Helen Conlon during the jewelry workshop put on by Holly Burrows.
Lionfish earrings made by Helen Conlon during the jewelry workshop put on by Holly Burrows.

Invasive lionfish in the Caribbean have a spawning rate of 30,000 eggs every four days, while having no predators in their invasive range. They also have the potential to reduce the abundance of fish on a reef by over 80%. The Slayer Campaign, established by CEI, encourages the fishing and spearing of lionfish by local fisherman by paying fishermen for their catch efforts ($11/lb of lionfish fillet). Removing lionfish from local reefs not only benefits the coral ecosystem but, also provides CEI and the reef team with more lionfish to dissect for research. Discussing and displaying this ongoing research and effort with tourists and locals made lionfish day at The Blue Seahorse a huge success!

 

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Sea turtle adventures in Savannah Sound with Fishbone tours

Last week the CEI Sea Turtle Research Team had the opportunity to collaborate for the third time with Julius Rankine, who operates Fishbone Tours in Savannah Sound. Julius offers interactive expeditions including fishing, snorkeling, and learning about local wildlife conservation. For the last six years, he has also offered a turtle catching experience, contributing data to our sea turtle database. After hundreds of turtle chases, he has gained extensive knowledge of the turtles’ habitat and behavior, and the best ways to catch them.

The sea turtle team and Julius aboard his boat in Savannah Sound.
The sea turtle team and Julius aboard his boat in Savannah Sound.

Our day was spent getting to know the area, learning about where each species of turtles can be found, and practicing the Bahamian method of catching a turtle. Julius was entertained by our official method of jumping off the side of the boat and swimming after the turtle, but didn’t think we would ever catch it. Instead, members of the team tried diving off the bow to get our hands on the turtle when they came up for air to avoid the tiring swim. The team caught and tagged eight new green sea turtles with his method, but the ninth proved too smart to let the boat get close. Finally, one of our interns jumped in the water, swam, and dove to capture the individual, proving that sometimes it takes more than one method to catch a turtle.

Interns prepare to tag one of the nine new juvenile green sea turtles.
Interns prepare to tag one of the nine new juvenile green sea turtles.

Julius was able to teach us a great deal about Savannah Sound and the local turtle populations, while we shared more of our methods and research background with him.  Tagging in Savannah Sound would present the opportunity to catch a new group of green sea turtles, as well as hawksbills and loggerheads, which are much more rarely caught and tagged around Eleuthera.

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Global Fin Print: Southern Bahamas

On May 6th, Associate Research scientist Dr. Owen O’Shea and Shark Research and Conservation Program (SRCP) intern Nicole Firing from The Cape Eleuthera Institute (CEI) headed to San Salvador Island and Conception Island to start continue the Global Fin Print project in collaboration with The School of Marine and Atmospheric Science (SoMAS) at Stony Brook University, New York.  Global Fin Print is an initiative that brings together elasmobranch researchers to help understand and fill knowledge gaps in the relative abundance of shark populations globally. Collaborators and researchers from multiple institutions world-wide have joined forces to better understand the influence of elasmobranchs on reef systems. Global Fin Print’s goal is to implement conservation efforts in areas where shark populations seem to be diminishing and provide an open-access database to the public for scientific and educational purposes. CEI partnered with SoMAS in to sample different parts of The Bahamas including Andros, Nassau, Conception Island, San Salvador Island and the Exuma Cays.

A nurse shark (Ginglymostoma cirratum) attempting to take a bite from the bait cage while a Caribbean reef shark (Carcharhinus perezi) and bar jack (Carangoides ruber) swim behind during a baited remote underwater video (BRUV) off of San Salvador Island, the Bahamas.
A nurse shark (Ginglymostoma cirratum) attempting to take a bite from the bait cage while a Caribbean reef shark (Carcharhinus perezi) and bar jack (Carangoides ruber) swim behind during a baited remote underwater video (BRUV) off of San Salvador Island, the Bahamas.

San Salvador saw a total of 50 baited remote underwater video (BRUV) deployments across a spatial scale of almost 20 miles along the shelf reefs of the western side of the island. Each deployment ‘soaked’ for 90 minutes resulting in in 75 hours of footage. With over 50 world class dive sites located off the coast of San Salvador, this sampling area has been drawing divers in for many decades because of the steady population of reef sharks. Common species recorded were the Caribbean reef shark, nurse shark, Nassau grouper, red hind grouper, mutton snapper, bar jack and yellow tailed snapper.

The second sampling location was the stunning and uninhabited Conception Island – 42 miles south west of San Salvador. Conception Island is a plateaued island in the Southern Bahamas with an extensive mangrove creek system taking up a large majority of the island and a large lagoon on the windward side of the island. This land and sea park has been a no take marine reserve for 5 years, is an important nursery for juvenile green turtles and nesting grounds for a range of birds including the magnificent tropicbird. This island also has the longest continuous ‘Montastrea’ coral reef in The Bahamas. The team deployed 40 units totoalling 60 hours of footage and common visitors the cameras were Caribbean reef sharks, juvenile tiger sharks (Galeocerdo cuvier) and nurse sharks.

 A juvenile tiger shark (Galeocerdo cuvier, right) and a Caribbean reef shark (Carcharhinus perezi, left) swim by a baited remove underwater video (BRUV) off the coast of Conception Island, the Bahamas. Also pictured is a Nassau grouper (far left).
A juvenile tiger shark (Galeocerdo cuvier, right) and a Caribbean reef shark (Carcharhinus perezi, left) swim by a baited remove underwater video (BRUV) off the coast of Conception Island, the Bahamas. Also pictured is a Nassau grouper (far left).

The trip was hailed a success and will contribute to the growing knowledge base on our oceans top level predators. CEI would like to thank SoMAS and Stony Brook University for their continued partnership in ongoing research to understand the knowledge gaps of apex predators in The Bahamas.

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Ecosystem Based Management Tools Training

In April, Candice attended the Coastal-Marine Ecosystem Based Management (EBM) Tools Training in San Juan, Puerto Rico facilitated by Nature Serve. Thank you to Kinship Conservation Fellows for supporting Candice’s attendance to this event. EBM Tools Network, a global network of coastal-marine EBM practitioners, researchers, and tool developers, facilitated the training workshop. The session was designed to address the needs of coastal-marine conservation and management practitioners.

The marine spatial planning and marine protected area  planning and management group
The marine spatial planning and marine protected area planning and management group

Ecosystem-based management is an environmental management approach that recognizes the full array of interactions within an ecosystem, including humans, rather than considering single issues, species, or ecosystem services in isolation (Christensen et al. 1996, McLeod et al. 2005). Because humans depend on an array of ocean and coastal functions— including fish as food, for example — EBM recognizes that our welfare and the health of the environment are linked. Put another way, marine and coastal systems provide valuable natural services, or “ecosystem services”, for human communities. Therefore, to protect our long-term wellbeing, we need to ensure marine and coastal ecosystem functions and productivity are managed sustainably. This means managing them in a way that acknowledges the complexity of marine and coastal ecosystems, the connections among them, their links with land and freshwater, and how people interact with them (UNEP (2011): Taking Steps toward Marine and Coastal Ecosystem-Based Management – An Introductory Guide).

Candice chose to join the marine spatial planning (MSP) and marine protected area (MPA) planning and management theme for the training session. The group discussed stakeholder engagement and co-management strategies for MSP and MPA planning and management, learning from examples in Colombia and Grenada. The group was given an introduction and overview of the United Nations Environment Program (UNEP), Caribbean Marine Protected Areas Management Network and Forum (CaMPAM).

Dr. Martha Prada from UNEP gave a presentation on Design, Declaration and Implementation Strategies of the Seaflower MPA, a case of EBM in the Caribbean. This case study showed the complexities of MPA planning in Colombia and the need to engage all stakeholder groups, promote sustainable development in local communities, research & monitoring, environmental education, alternative livelihoods, licenses/permits, control pollution, and the implications of changing political climate.

Roland Baldeo, the National Marine Protected Area Coordinator for the Government of Grenada, discusses the need for co-management in conservation planning
Roland Baldeo, the National Marine Protected Area Coordinator for the Government of Grenada, discusses the need for co-management in conservation planning

Roland Baldeo, the National Marine Protected Area Coordinator for the Government of Grenada, gave an example of applied EBM by incorporating pig farmers into MPA management plans. This was achieved by educating farmers about the importance of safeguarding coral reefs and associated ecosystems through sustainable land management practices. By taking farmers on excursions to the areas of coral reef being damaged by pig waste run-off, they were able to demonstrate the linkages between sustainable land management practices and the health of marine ecosystems. This formed the Reef Guardian Farmers group, which recognizes and promotes practices such as proper fertilizer application and good water quality and soil management practices utilized by farmers.

Candice learning how to use Sea Sketch software
Candice learning how to use Sea Sketch software

Finally participants were trained to use Sea Sketch software by performing exercises from a MPA planning scenario in Barbuda using the program. This unique software enables users to not only incorporate biological data and habitat maps but also allows socio-economic data to be collected from stakeholders via an online link. This information is then visualized as a layer on the map. Fishermen in Barbuda were asked to identify their most important fishing sites, this allows for analytics to be run threw the software to quantify how many fishermen would be displaced based on various MPA placement scenarios, whilst also considering habitat and biological data.

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Shark Research and Conservation Program facilitates another successful year of Oceanic Whitetip (Carcharhinus longimanus) tagging at Cat Island

April saw the sixth successful annual research cruise to study oceanic whitetip sharks at Cat Island. Since 2011, the Shark Research and Conservation Program, along with long-term collaborators Microwave Telemetry Inc (www.microwavetelemetry.com), Stony Brook University, University of North Florida, and Florida International University, have worked closely to answer a number of questions pertaining to the life-history and behavior of a known oceanic whitetip shark aggregation at Cat Island, The Bahamas.  The project is supported and co-funded by Blue Ocean Institute, Save Our Seas Foundation, and the Moore Bahamas Foundation.

Working up an oceanic whitetip and attaching a satellite tag.
Working up an oceanic whitetip and attaching a satellite tag.

Historically, oceanic whitetip sharks were naturally abundant, and a common apex predator across the tropical and sub-tropical western Atlantic. However in the past 50 years, whitetip populations have come under severe threat as a result of the global fin trade. Oceanic whitetips are now categorized as ‘critically endangered’ in the Western Atlantic by the International Union of the Conservation of Nature (IUCN). Despite these pressures, the biology and ecology of this species remains highly elusive, highlighting a critical need for collection of these data from a management and conservation perspective.

The goals of the study are to:

  1. Determine generalized movements and determine high-use areas of sharks in relation to the Bahamas shark sanctuary.
  2. Examine diving behavior through high resolution temperature and depth data.
  3. Investigate potential hormone markers to identify reproductive cycles.
  4. Examine prey-preference potential seasonal diet switches through tracing relative concentrations of Carbon and Nitrogen isotopes.
  5. Gather baseline genetics data which will be incorporated into fin-trade management, and will detect fins from Oceanic whitetips found in the Western Atlantic.

This year, over a six day cruise, the team captured and released a total of 15 oceanic whitetips, and attached pop-up satellite tags (PSAT’s) measuring archived temperature, depth and light levels(used to define location) to 12 females. The tags are pre-programmed to record for a desired deployment duration ranging from 14 days to 12 months before detaching from the animal. Once the tag detaches, a sub-set of archived data is transmitted to a satellite system, meaning the tag does not need to be recovered.  The main focus of this year’s cruise was to tag confirmed pregnant (via ultrasound) and recaptured individuals, to identify hormone pregnancy markers, and potential pupping grounds.

The oceanic whitetip shark (Carcharhinus longimanus). Photo by Sean Williams.
The oceanic whitetip shark (Carcharhinus longimanus). Photo by Sean Williams.

Investigating these large knowledge gaps are intrinsic to the contemporary management of oceanic whitetip shark populations, and will provide novel insights into the biology and ecology of a severely threatened apex predator.

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