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Carvalho, I., Brito, C., Reiner, F. and dos Santos, M. E., "Records of cetaceans around Ilhéu das Rolas, S.tomé and Príncipe ", 17th Conference of the European Cetacean Society. Abstract: Ilhéu das Rolas is a small equatorial Atlantic island located in the south part of the S. Tomé and Príncipe archipelago. This area has been considered a breeding ground for the humpback whales (Megaptera novaeangliae), who have been the target of a whale hunt from the XIX century until late XX century. In the last years the sightings of humpback whales have increased in S. Tomé (information from fishermen and personal observations in 2001) which may indicate that the whales are returning to this breeding ground. In 2002, between August and December, boat-based surveys were conducted in order to study the occurrence of cetaceans off Ilhéu das Rolas. Sightings of humpback whales, bottlenose dolphins (Tursiops truncatus), pantropical spotted dolphins (Stenella attenuata) and orcas (Orcinus orca) were recorded, as well as the stranding of a dead sperm whale (Physeter macrocephalus). Data on the cetaceans’ relative abundance and distribution, their group composition, habitat use and acoustic emissions were obtained to investigate their ecology and behaviour, and stock affiliation in the case of the humpback whales. This oceanic island seems to be an important area for cetaceans, probably due to large concentrations of prey as well as the existence of several small bays and shallow waters that constitute preferred rest areas. Efforts are being made to establish a careful and sensible whale watching program. |
