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Conservation status of shark species in West Africa: strategy for the preservation of shark species threatened
Dossa S. Justine, Diop Mika S., Harrison Lucy, Nicholas Dulvy - FIBA, CSRP, IUCN Shark Specialist Group2011
Poster présenté à la 15ème Conférence scientifique de l’Association Européenne des Elasmobranches (EEA), Berlin, octobre 2011 - Sharks and rays have faced uncontrolled exploitation in West Africa for many years. In 2004 we began promoting the sustainable management of shark populations in seven countries of the Sub-Regional Fisheries Commission (SRFC) - Gambia, Cape Verde, Guinea, Guinea-Bissau, Mauritania, Senegal and Sierra Leone. The intensive exploitation of sharks over the last thirty years has resulted in a number of threatened populations. Some species are already extinct locally, as it is the case for Pristidae (sawfish). The Rhynchobatidae (guitar-rays) have also virtually disappeared throughout the Sub-Region, except on the Banc d'Arguin, Mauritania. Other species, like the great hammerhead shark Sphyrna mokarran and the lemon shark Negaprion brevirostris are also threatened. In the sub-region, the number of many shark species has decreased in all large species. In general, there is a deterioration of the status of all species and clear risks for the larger species. The update of the IUCN Red List for the Sharks in West Africa in 2006, thanks in part to the project results from PSRA Requins, shows that species that still seemed to have a reasonable overall status are already Endangered or Critically Endangered with extinction in the region. Thus, 35% of them are threatened - 5% are Critically Endangered, 7% are endangered and 23% are Vulnerable. This work provides an analysis of the situation of threatened species in order to offer a better strategy for their conservation.
pdf (411,35 ko)
Preliminary Results of Elasmobranch bycatch in Sub regional Fisheries Commission region, West Africa
Diop S. Mika, Dossa Justine - Sub Regional Fisheries Ccommission, FIBA2011
Poster présenté à la 15ème Conférence scientifique de l’Association Européenne des Elasmobranches (EEA), Berlin, octobre 2011 - In the Sub-Regional Fisheries Commission (SRFC) region - Cape Verde, Gambia, Guinea, Guinea-Bissau, Mauritania, Senegal and Sierra Leona - the declared shark landings are estimated from less than 1000 tons to more than 30 000 tons between 1995 and 2005. After this period, an important decline was observed. Meanwhile the industrial fleets catch a significant numbers of pelagic and demersal species as bycatch. Resting on this, it was deemed necessary to evaluate these incidental captures to establish how much they contribute to the shark fishing pressure in the region. According to estimates, bycatch reached a maximum of approximately 12,000 tons in 1996 in all SRFC countries and are stabilized about 10000 tons for the rest of the period under review (even though some figures are missing for Guinea-Bissau from 1995 to 1999). For the remaining period, Mauritania, Guinea and Cape Verde contributed the bulk of the catch with more than 95% of the total.
pdf (663,77 ko)
Sharks conservation in the seven Countries of Sub-Regional Fisheries Commission, West Africa: do we have any evidence of overexploitation
Diop Mika, Dossa Justine - FIBA, Sub Regional Fisheries Commission (SRFC)2011
Poster présenté à la 15ème Conférence scientifique de l’Association Européenne des Elasmobranches (EEA), Berlin, octobre 2011 - In West Africa, the intensive exploitation of shark populations since the 1990s has resulted in the collapse of the fisheries, the loss of biodiversity and dwindling of shark resources. Hence the Sub-Regional Action Plan for conservation and sustainable management of shark populations (PSRA-Requins) project was launched in 2004 to promote a sustainable shark resource management strategy within the Sub-Regional Fisheries Commission (SRFC) region-Cape Verde, Gambia, Guinea, Guinea Bissau, Mauritania, Senegal, Sierra Leone.The project contributes towards the establishment of the status of shark conservation, and show increase in landings in all countries across the region. This poster presents some preliminary signs that could arise from serious threat of sharks and rays in the region
pdf (452,60 ko)
Colloque international sur les Requins : Résumé des communications/Book of abstracts
Mika Diop, Justine Dossa, Hamady Diop - CSRP, FIBA, PRCM2011
Résumés des communications faites lors du "Colloque international sur la conservation et la gestion durable des populations de Requins en Afrique de l'Ouest : Bilan et perspectives ", qui s'est tenu à Dakar (Sénégal) du 25 au 27 juillet 2011.
pdf (2,97 Mo)
Cryptic vicariance of Northeastern Pacific and Gulf of California angel shark (Squatina californica) populations. Evidence from Mitochondrial sequences.
Ramíez-Amaro, S.R.; R. Vázquez-Juárezand F. Galván-Magaña. - Departament of Fisheries, Centro Interdisciplinario de Ciencias Marinas, Laboratory of Biotechnology of Marine Organisms, Centro de Investigación Biológica del Noroeste2011
Poster présenté lors du colloque international sur la conservation des Requins en Afrique de l'Ouest (Dakar, 25-27 juillet 2011).
pdf (1,38 Mo)
