Social organization of female sperm whales and their offspring: constant companions and casual acquaintances

Research paper by Hal Whitehead, Susan Waters, Thomas Lyrholm

Indexed on: 01 Dec '91Published on: 01 Dec '91Published in: Behavioral Ecology and Sociobiology


Associations among female sperm whales, Physeter macrocephalus, and their dependent offspring, off the Galapagos Islands were studied between 1985 and 1989. The whales were found in groups containing about 23 individuals, with each individual having approximately 12 constant (over years) companions. These permanent units associated with one another for periods of ≅6.5 days, although the rate and duration of these associations seemed to vary between years, perhaps because of differences in the food supply. The principal function of the closed units may be care of the offspring, and units in the same general area may derive benefit from feeding in a coordinated manner.