Elasmobranch (sharks, skates and rays) landings in recent years have increased significantly, mainly the result of greater interest and valorization of some products such as fins in the Asian markets, but also due to the by-catch in many fisheries around the world targeting other species. Yet, not much is known about most of these elasmobranch species biology, and many populations may be currently facing serious threats/declines.
Oceanic pelagic sharks pose a particular difficult problem when it comes to fisheries management and conservation, as they migrate between territorial waters of different countries and international waters, between continents and hemispheres. On the other hand, these sharks are regularly caught by different fishing gears and during different fisheries in a more or less targeted way.
Not only these species are extremely vulnerable to fisheries, but they are also very poorly known, and it is therefore urgent to carry out more biological research to allow for enlightened fishery management and conservation. Such better and improved data has been requested by the International Commission for the Conservation of Atlantic Tunas (ICCAT), the international management body of these species in the Atlantic Ocean.
Pelagic sharks are commonly caught as by-catch in the tuna and swordfish longline fishery that takes place along the Atlantic Ocean. Those pelagic sharks are highly migratory. An integrated inter-continental and inter-hemispheric approach is needed for their efficient study, management and conservation.
To study the biology, population dynamics, population genetics, movement patterns and habitat use of pelagic sharks in the Atlantic Ocean.
The current focus of this research initiative has been on the pelagic species that are impacted by long-line fisheries, and include:
- Blue shark, Prionace glauca
- Mako shark, Isurus oxyrhynchus
- Bigeye thresher, Alopias superciliosus
- Smooth hammerhead, Sphyrna zygaena
- Oceanic whitetip shark, Carcharhinus longimanus
- Crocodile shark, Pseudocarcharias kamoharai
The data is being collected by fishery dependent sampling by fishery observers on board commercial long-line vessels.