Revista de biología marina y oceanografía
versión On-line ISSN 0718-1957
AGUAYO-LOBO, Anelio et al. Southern right whales, Eubalaena australis (Desmoulins, 1822) off Chile: analyses of records from 1976 to 2008 . Rev. biol. mar. oceanogr. [online]. 2008, vol.43, n.3, pp. 653-668. ISSN 0718-1957. http://dx.doi.org/10.4067/S0718-19572008000300024.
Sighting data of Eubalaena australis from Chilean waters from 1964 to 2008 were analyzed. During these 44 years, 124 sightings of 232 whales were recorded, including 39 calves. Whales were sighted in three main areas: i) north of 47°S, ii) Magellan Strait and Beagle channel, and iii) Drake Passage and Antarctica. A higher frequency of sightings occured between August and October. Most of calves were recorded north of 41°S, being concentrated between 23°S and 25°S, and also between 32° and 36°S. Group sizes ranged from 1 to 7 whales, in the area north of 47°S pairs were more common, while for the two areas south of 47°S, whales were most commonly sighted singly. The population trend, considering only whales north of 47°S, showed an increase (although not statistically significant) between 1976 and 2008, but when only calves were considered, there was no increase, suggesting that both rates would be underestimated. We highlight the need for an increase in sighting effort for southern right whales as well the development of a systematic program for monitoring, photo-identification and molecular study. These measures would improve the demographic knowlegde and therefore provide a sound basis for evaluation of the status of this species, which is currently considered as `In Critical Risk' in Chilean waters.
Palabras clave : Sightings; distribution; reproduction; population trend; Chile.