Scientific Literature: Searchable Database

A survey of the status of cetaceans in Senegal, The Gambia and Guinea-Bissau (Project WAFCET I) was undertaken in 1997-98 sponsored by UNEP/CMS to start a projected longterm international effort to stimulate broad regional involvement in research and conservation of West African cetaceans. Partners included, in Senegal, the Institut Fondamental d'Afrique Noire, Universit‚ Cheikh Anta Diop (IFAN-CAD) and the Centre de Recherches Oc‚anographiques de Dakar-Thiaroye (CRODT); in The Gambia, the Department of Parks and Wildlife Management (DPWM); and in Guinea-Bissau the Centro de lnvestiga‡ao Pesquero (CIPA) and IUCN-Bissau office; however field activities in GuineaBissau were abandoned due to the 1998 war. The status, distribution and biological characteristics of 24 species of dolphins and whales confirmed to occur in the study area were reviewed. The authors collected new biological voucher material, such as skeletal specimens, soft tissues, samples for genetic studies and photographic evidence of several dozens of individuals of 11 cetacean species. Included are the first recognized specimens of minke whale (Balaenoptera acutorostrata) and sei whale (Balaenoptera borealis) for Senegal, the first records of Clymene dolphin (Stenella clymene) and short-finned pilot whale (Globicephala macrorhynchus) for The Gambia and the first Fraser's dolphin (Lagenodelphis hosei) for mainland West Africa. Both long-beaked common dolphins (Delphinus capensis) and short-beaked common dolphins (Delphinus delphis) were shown to occur off Senegal, their intraspecific variability is under study. A total of 269 historical specimens, most of them skulls, were registered in a comprehensive review and rehabilitation of the IFAN cetacean collection curated at IFAN-CAD (73 specimens) and the Mus‚e de la Mer on Gor‚e Island (196 specimens): Balaenoptera acutorostrata (3), Balaenoptera borealis (1), Balaenoptera sp. (2), Delphinus capensis (83), Delphinus cf. capensis (17), Delphinus delphis (11), Delphinus cf. delphis (7), Delphinus sp. (43), Globicephala macrorhynchus (10), Orcinus orca (3), Phocoena phocoena (10), Physeter macrocephalus (2), Tursiops truncatus (34), Sousa teuszii (15), Stenella sp. (4), Steno bredanensis (14), Ziphius cavirostris (1), and material of unidentified cetaceans (7). Although no cetacean catch rates could be estimated, both empirical and circumstantial evidence was gathered for dolphin by-catches and direct takes in Senegal and The Gambia. Low to moderate mortality levels in fisheries seem to occur in most of the study area, except Guinea-Bissau for which there is no information. While there were no indications of substantial directed takes, these could occur covertly. Most fishermen are acutely aware of the legal protection of dolphins. Detection avoidance strategies include the hiding of fresh carcasses, burial on the beach or offshore dumping of butchered remains. Cetacean meat is a local commercial commodity and is consumed covertly in several places. Confirmed catches include Atlantic hump-backed dolphin (Sousa teuszii), bottlenose dolphin (Tursiops truncates) and a short-finned pilot whale. Circumstantial evidence from small boat surveys, stranded remains and fisheries monitoring, suggests that the Atlantic hump-backed dolphin has become fairly rare off Senegal and The Gambia. Only in Guinea-Bissau were hump-backed dolphins sighted with any regularity during boat sorties. Also, its range was found to be considerably more limited than previously assumed and does not seem to include true riverine habitat. Where occurring in outer estuaries, these had predominantly marine characteristics. All verifiable dolphin sightings and catches upstream of the estuary of the Gambia and Casamance rivers were identified as T. truncatus. Artisanal fishing effort has dramatically increased over the past decade both in the number of fishermen and the number of boats, and by-catches in artisanal fisheries continue to affect several species, especially bottlenose dolphins living near-shore and Atlantic hump-backed dolphins. Catches, in conjunction with expanding coastal development, may be fracturing the hump-backed dolphin's range. Reproductive isolation would be a serious threat to the species' long-term survival. The Saloum delta (including Sin‚, Saloum, Diombos and Bandiala), part of which constitutes Senegal's Parc National du Saloum, the adjacent waters of The Gambia's Niumi National Park and the outer estuary of the Gambia river constitute a major refuge area for Atlantic hump-backed dolphins and deserve the highest possible protection. If .further work confirms the precarious status of the species, an Appendix I listing on the CMS Convention will be necessary. Dedicated commercial dolphin-watching is firmly established only on the Gambia River; in Senegal's Saloum delta it is practised only incidentally. Although no current problems were noted, for an efficient regulation we recommend that a licensing system and an official code of conduct for tour operators be adopted, as well as an enforcement scheme. It is recommended also that The Gambia government would proceed with the ratification of the CMS Convention at its earliest convenience, as to ensure maximum protection for aquatic mammals and other wildlife in the region. The Tanji Bird Reserve with Bijol Islands and associated inshore waters, as well as the Kiang West National Park on the south bank of the Gambia River, are conservation areas which protect confirmed cetacean habitat. In November 1997 'Conservation and Research of West African Aquatic Mammals' (COREWAM) was launched, the first NGO of its kind in sub-Saharan West Africa. Principal aims are to stimulate local involvement at grass-roots level in: (1) the implementation of scientific research of cetaceans and manatees; (2) promotion of the conservation of aquatic mammals in the West African region; (3) organization of aquatic environmental education. The scope is long-term and regional via wide membership throughout West Africa.