Abstract: A cetacean line-transect survey was conducted in the eastern Caribbean Sea and the adjacent southwestern North Atlantic Ocean from 17 April to 14 May 2004 to obtain information on cetacean distribution and density. The survey area was divided into coastal and offshore blocks; the coastal blocks contained the insular continental shelf. A total of 2,273 nmi (4,210 km) was searched (1,528 nmi [2,830 km] in coastal blocks and 745 nmi [1,380 km] in offshore blocks) with 76 cetacean sightings (64 and 12 for the coastal and offshore blocks, respectively). Twelve species were identified (number of individuals/groups observed in coastal blocks-offshore blocks): 4/4(2/2) Bryde’s whale (Balaenoptera edeni), 7/5(2/1) humpback whale (Megaptera novaeangliae), 5/5(0/0) sperm whale (Physeter macrocephalus), 32/3(0/0) short-finned pilot whale (Globicephala macrorhynchus), 132/4(0/0) melon-headed whale (Peponocephala electra), 1/1(0/0) Risso’s dolphin (Grampus griseus), 42/6(0/0) bottlenose dolphin (Tursiops truncatus), 30/1(0/0) Fraser’s dolphin (Lagenodelphis hosei), 505/9(33/3) pantropical spotted dolphin (Stenella attenuata), 35/1(35/1) Atlantic spotted dolphin (S. frontalis), 35/1(0/0) spinner dolphin (S. longirostris), and 90/1(0/0) striped dolphin (S. coeruleoalba). Additionally, 28 groups were sighted for which the species could not be identified: 5/5(2/2) large whales, 11/5(0/0) Mesoplodon spp., 1/1(0/0) ziphiid whale, 5/1(0/0) Stenella spp., and 39/11(10/3) dolphins. Due to the low number of sightings on account of the poor sighting conditions during the survey, abundance of cetaceans could not be estimated.

Key Words: cetacean, whale, dolphin, distribution, density, Caribbean Sea, Lesser Antilles, North Atlantic, sighting survey

Document Type: Research article

DOI: 10.1578/AM.36.2.2010.154

Page Numbers: 154-161