T. Tamura et al., DIET OF MINKE WHALES BALAENOPTERA-ACUTOROSTRATA IN THE NORTHWESTERN PART OF THE NORTH PACIFIC IN SUMMER, 1994 AND 1995, Fisheries science, 64(1), 1998, pp. 71-76
The forestomach contents of 114 minke whales Balaenoptera acutorostrat
a randomly sampled in the northwestern part of the North Pacific in th
e summer of 1994 and 1995 were analyzed. Twelve prey species consistin
g of 7 fishes, 4 euphausiids and 1 copepod were identified. Pacific sa
ury Cololabis saira was the most important prey species, occurring in
77.2% of the stomachs and composing 80.6% of the weight ingested, with
some spatial and temporal variation. Japanese anchovy Engraulis japon
icus was the next most important prey species, occurring in 14.0% of t
he stomachs and composing 6.7% of the weight ingested. Diurnal changes
in the mean forestomach content weight and in the relative freshness
of the forestomach contents showed little change between 06:00-18:00 h
. The minke whales fed mainly on pelagic schooling fishes at the surfa
ce in the daytime.