Komunitas cetacea dan karakteristik habitatnya di perairan Selat Ombai

Abstract

As part of collaborative research INSTANT, this research aimed to explore spatio-temporal distribution of cetacean community observed in the Ombai Strait, as well as to study its biophysical characteristics, as the key to understanding cetacean habitat dynamics. During two research cruise in the Ombai Strait, December 2003-January 2004 and June-July 2005, cetacean community was assessed visually and resulted in consistent sightings of three apex predator cetacean species, e.g. Stenella longirostris, Pseudorca crassidens, and Physeter macrocephalus. The first two species were observed with large number of individuals, with foraging and feeding behavior. INSTANT Cruise I deployed 54 survey hours resulting in 5 positively identified cetacean species (Tursiops truncatus, Stenella longirostris, Pseudorca crassidens, Orcinus orca, Physeter macrocephalus), originated from 11 sightings, with estimated number of abundance 908 individuals; while INSTANT Cruise II resulted in 60 survey hours, 4 positive identification (Stenella longirostris, Pseudorca crassidens, Physeter macrocephalus, Kogia simus), 15 sightings, and 698 individuals. In general, 71.6% of cetacean sightings were at morning time (5:00-7:00 and 7:00-10:00 local time).