blue whale, Balaenoptera musculus, is the largest
of all the cetaceans, averaging 26 m in length and weighing
up to 136 MT. The body is bluish gray in color and often mottled
with white spots. The dorsal fin is quite small (<30 cm)
and is located further down the back than in other whale species
(Leatherwood et al. 1976).
whales are planktivorous, feeding on dense patches of krill,
often lunging or rolling at the surface when consuming their
prey. The gestation period is about 12 months, and females
calve every 2-3 years. Calves are 7-8 m in length and can
weigh up to 3.6 MT. Three subspecies have been described to
date: B.m. intermedia, from the southern hemisphere,
B.m. musculus, from the northern hemisphere Atlantic
and Pacific oceans, and B.m. brevicauda, the pygmy
blue whale (Yochem and Leatherwood 1985).
north Pacific blue whale population is estimated to number
between 1400-2000 individuals (Mizroch et al. 1984,
Yochem and Leatherwood 1985, Barlow 1994). Recent studies
indicate the number of animals found along the coast of central
California appears to be increasing (Calambokidis et al.
1990, Barlow 1994.