MEPS 168:1-11 (1998)  -  doi:10.3354/meps168001

Clustering and aggregations of minke whales in the Antarctic feeding grounds

Fujio Kasamatsu1,*, Paul Ensor2, Gerald G. Joyce3

1Marine Ecology Research Institute, 3-29 Jinbo-cho, Kanda, Chiyoda, Tokyo 101-0051, Japan
2Governor¹s Bay, Lyttelton RD1, New Zealand
3Moon Joyce Resources, 11740 Exeter Avenue, N.E., Seattle, Washington 98115, USA

ABSTRACT: Information on the degree of clustering and aggregation behavior of whales is extremely limited. To obtain such information within various survey areas would not only be of help in understanding cetacean ecology, but also in optimizing the survey design in order to obtain abundance estimates with minimal variance. The clustering and aggregation patterns of minke whales Balaenoptera acutorostrata were examined using the data derived from systematic sighting surveys in 3 major feeding grounds in Antarctic waters. Distribution patterns showed that minke whales clustered in the Antarctic feeding grounds but were relatively randomly distributed within the aggregations, with the possibility that schools within the aggregation tend to avoid each other. Higher clustering was observed in areas within bays (Ross Sea and Prydz Bay) than in areas of open water (Weddell Sea). Mean school sizes were positively correlated with density. Aggregation patterns in relation to density and abundance in Antarctic waters are presented.

KEY WORDS: Minke whale · Distribution · Aggregation · Clustering · Antarctic · Ross Sea · Weddell Sea · Prydz Bay · Sighting survey

Full text in pdf format