The occurrence and distribution of dolphins in Zanzibar, Tanzania, with comments on the differences between two species of Tursiops
2005 (English)In: Western Indian Ocean journal of marine science, ISSN 0856-860X, Vol. 4, no 1, 85-93 p.Article in journal (Refereed) Published
Incidental catches (bycatch) in gillnet fisheries off Zanzibar (Unguja Island), as asource of mortality among several species of dolphins, were reported in a questionnaire surveyconducted in 1999. As a follow-up to that survey, from January 2000 to August 2003, wemonitored the incidental catches of dolphins collected from 12 fish landing sites. Six species ofdolphins were recorded from 143 specimens retrieved from bycatches in drift- and bottom setgillnets. Of these, 68 (48%) were Indo-Pacific bottlenose dolphins (Tursiops aduncus), 44 (31%) spinner dolphins (Stenella longirostris), 12 (8%) Risso’s dolphins (Grampus griseus), 11 (8%) Indo-Pacific humpback dolphins (Sousa chinensis), 6 (4%) Pan-tropical spotted dolphins(Stenella attenuata) and 2 (1%) common bottlenose dolphins (Tursiops truncatus). Most of thebycatches (71%) were in nets set off the north coast of Unguja Island. In this paper, bycatchrecords are examined to describe the occurrence and distribution of dolphin species in UngujaIsland coastal waters. The relatively large numbers of bycatch dolphins recorded indicate thatbycatch may be a potential threat to local populations that need to be addressed in futureconservation and management efforts in the region.
Place, publisher, year, edition, pages
2005. Vol. 4, no 1, 85-93 p.
incidental catch, occurrence, distribution, dolphins, Unguja Island, Zanzibar
Research subject Animal Ecology
IdentifiersURN: urn:nbn:se:su:diva-34438OAI: oai:DiVA.org:su-34438DiVA: diva2:284796
ProjectsSustainable dolphin tourism in east Africa