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.
Dr Steven Kessel gained his PhD in marine ecology and biology from Cardiff University, UK, conducting his field work at the Bimini Biological Field Station in The Bahamas. Following the completion of his degree in 2009, he spent two years at Cardiff University as a postdoctoral fellow, acting as the principal investigator for the Jupiter Large Coastal Shark Species Study, which investigated the biology and ecology of large coastal shark species resident off the eastern seaboard of the USA. Since then, Steven has worked for the University of Windsor Great Lakes Institute for Environmental Research as the principal...
Dr Kevin Feldheim received his PhD in 2002 from the University of Illinois at Chicago. He has been working at the Field Museum in Chicago as the A. Watson Armour III manager of the Pritzker Laboratory for Molecular Systematic and Evolution since 2001. His work entails using genetic markers to examine the mating system and population genetics of elasmobranchs. One of his main projects is leading the genetic studies of lemon sharks from Bimini. This project encompasses a 25-year sampling period that has provided insight into several aspects of elasmobranch mating biology.
To describe the population connectivity of the Endangered Caribbean reef shark at both fine and large scales throughout its range and to inform the development of effective conservation management to ensure the species’ survival and recovery.
In 2021, the Caribbean reef shark was designated Endangered on the IUCN Red List, with the overall population found to be decreasing. Targeted and caught as bycatch in areas without protection, populations have declined by up to 99% over the past three generations. Where effective protection measures exist, however, populations have remained stable since the 1980s, demonstrating the potential for stabilising decreasing populations and promoting recovery by implementing appropriate conservation measures.
The Caribbean reef shark Carcharhinus perezi is a Carcharhiniform that grows to about three metres (10 feet) in total length and functions as a key mid- to upper-level predator in coral reef ecosystems through the tropical and subtropical western Atlantic. Abundant on healthy reefs, it is considered to have a strong controlling influence on ecosystem balance and health. In addition to its value in maintaining ecosystem health, it has a high ecotourism value as one of the most common species associated with shark dive tourism in the Caribbean region, particularly in The Bahamas. Unfortunately, it is also valued for its meat, fins, skin (leather), liver (oil) and carcass (fishmeal) and in many areas has been commercially exploited and taken as bycatch in gill-net and longline fisheries. In areas without protection, Caribbean reef shark populations have declined by up to 99% over the past three generations (about 29 years). This led to the species being classified as Endangered on the IUCN Red List in 2021, highlighting the need for increased conservation management intervention to ensure its persistence and recovery. A growing body of literature provides important life history, spatial ecology and regional abundance data, but a critical missing piece of the puzzle is an extensive analysis of population genetics throughout the species’ known range. Many researchers in the field of shark science have been sampling Caribbean reef sharks and stockpiling tissue samples for future analysis. This project provides the opportunity for these samples to contribute to the shark’s long-term conservation. With the samples already committed, this would constitute the most geographically expansive (and collaborative) genetic investigation of the species – an investigation that would lead to a comprehensive understanding of population genetics throughout the Caribbean reef shark’s range in terms of variability, recruitment potential for depressed areas and effective population size.
The overall aim of the project – to describe the population connectivity of the Caribbean reef shark throughout its range as it relates to its conservation – will be achieved through the following objectives:
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.
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.
Ramón is combining modern (environmental DNA, BRUVs and UAVs) and traditional methods to search for sharks and rays in two coastal nursery areas in Mexico. He wants to find essential shark areas on the Mexican Caribbean coast that can feed into the IUCN’s Important Shark and Rays Areas (ISRAs) process, putting key habitats on the map with the information needed to protect them. To do so, he’s reconstructing the past use of these coastal nurseries and comparing how sharks are using them now. Then he can see what’s changed, and decipher why that could be vital information to champion the restoration of Mexico’s shark nurseries.