Date of Award

1989

Degree Type

Major Paper

Degree Name

Master of Arts in Marine Affairs

Abstract

This paper reports original research from two recent studies in the Antarctic Peninsula area, reviews past sighting information and policies affecting mysticete whales, and recommends future research. Due to poor management by the International Whaling Commission, mysticete whales are among the most severely depleted species groups in the Antarctic. The combined total Antarctic harvest from 1920 to 19867 for blue Balaenoptera musculus, fin B. physalus, sei B. borealis, minke B. acutorostrata and humpback Megaptera novaeangliae whales was over one million animals. The effect of this hunting pressure is the dominant factor determing the present status of Antarctic mysticete whales and has probaly altered the trophic relationships of these and other Antarctic fauna. Dramatic changes, probably resulting from over-hunting, may have occurred in the species compositon of mysticete whales of the Peninsula area. Published estimates of abundance for mysticete whales of Antarctica do not agree with recent sightings data from the Antarctic Peninsula area. Fin, blue and sei whales were not seen and there are no records of these species from the Peninsula area during reent years. Humpback and right whale Eubalaena australis abundances appear greater than published estimates predict. New threats to whale populations are emerging as a result of growing interest in the Antarctic krill Euphausia superba fishery. The Antarctic Peninsula area is one of the primary sites of this krill fishery. the 1982 Convention for the Conservation of Antarctic Marine Living Resources (CCAMLR) rquires signatory nations to manage living resources from an ecosystem perspective, to maintain ecological relationships between harvested, dependent and related species and to restore depleted populatins. Mysticete whales prey on krill in the Antarctic and will be a key compenent in ecosystem models. Considering the uncertain status of mysticete whale populations, the emrging krill fishery, and the needs of the CCAMLR scientifi committee, additional surveys are needed in the Antarctic Peninsula area to provide current information on the composition, relative abundances and trophic relationships of these cetaceans for managementand ecosystem monitoring purposes.