Sharks and rays
With more than 400 million years, sharks coexisted with dinosaurs and as a group they survived mass extinction, diversifying into more than 1000 species of sharks and known rays, with new species discovered every year. Sharks and rays are part of a group called elasmobranchs, consisting of sharks with gill openings on the sides of the head and rays with gill openings under the head.
Elasmobranchs have a essential role in ecosystems, keeping the entire food chain healthy for removing sick / weak animals. They thus serve as indicators of the health status of our Oceans. As a group, they are extraordinarily diverse, varying between 18 meters in size and 20 cm and living from deep seas and abyssal plains to shallow coastal areas. As top predators in ecosystems, they are versatile and efficient animals, feeding on both fish and turtles, seals, whales and dolphins. Its sensory systems are refined for detecting prey. Smell is usually the first way to alert the shark to potential prey, especially if it is injured. The most sensitive species can detect the equivalent of 1 drop of fish oil in an Olympic swimming pool!
Unfortunately all shark and ray populations are rapidly declining. They are species sensitive to human action because they grow at a slow pace, take many years to reach adulthood and give rise to few offspring. For this reason, they are particularly vulnerable to fishing overexploitation. The shark fin trade is estimated to kill 100 million sharks annually, including the iconic whale shark. In national waters there are several species of sharks, Cape Verde being an important place for its life cycle. In our country, the unregulated dynamics of shark fishing by national and foreign vessels, imposed the need to adopt conservation measures, and fishing in Cape Verde is prohibited. 9 species of shark.
The work of the Biosphere
Several national and international partners participate in the work of the Biosphere with sharks and rays to gather essential information about the species. At the technical level, we can highlight the support of Dalhousie University, ShARCC, OTN and GEOMAR. In 2015 we started work on the Santa Luzia Marine Reserve, focusing mainly on the shark, Glaucostegus cemiculus, in “Danger of Extinction” and in Tubarão doninha do Atlântico, Paragaleus pectoralis, with “Deficient data” according to the Red List of the IUCN.
Species studied by the project: Glaucostegus cemiculus, Paragaleus pectoralis, Ginglymostoma cirratum, Carcharhinus limbatus, Carcharhinus brevipinna, Carcharhinus sp., mustelus, mustelus, Sphyrna sp., Galeocerdo cuvier, Taeniura gragata and Mubula tarapacana.