Dwarf Sperm Whale
and dwarf sperm whales are two little known deep ocean
dwelling cetaceans. Their habit of lying motionless near the
sea surface far from shore makes them difficult to detect.
Pygmy sperm whales are though to be more pelagic and dwarf
sperm whales more coastal (Reeves et al. 2002). Pygmy sperm
whales have been seen from Japan, Hawaii, Washington State
south to Chile and the Tasman Sea (Reeves et al. ). Dwarf
sperm whales are recorded from Japan to British Columbia south
to New Zealand and Chile.
usually occur alone or in groups of up to ten animals
(Caldwell and Caldwell 1989). Females are sexually mature when
they are 2.7 meters long, gestation in 9-11 months, calves are
1.2 m long at birth and nurse for a year (Wilson and Ruff
1999). It has a spermaceti organ. Stranded animals often have
plastic bags in their gut likely as a result of their
similarity to their squid prey. Both species have a unique
defense. Upon attack they evacuate dark red-brown syrupy
liquid into the water which when stirred up with the flukes,
conceals their presence to predators (Scott and Cordaro 1987,
Long 1991). The total length is about 2.7 meters and weight is
about 320 to 400 kilograms. They have ten sharp teeth on the
lower jaw and lack teeth on the upper jaw (Caldwell and
Caldwell 1989). Pygmy sperm whales utter clicks to communicate
(Santoro et al. 1989).
Length: 3 meters
Weight: 400 kg
Food: squid and octopus
Social Status: Commonly found
in groups of 3 - 5
annually to 1 calf
Gestation: 11 months
Newborn: 1.2 meters long
IUCN Red List Status: Lower
Sperm Whale Distribution Map
D. K. and M. C. Caldwell. 1989. Pygmy sperm whale Kogia
breviceps; dwarf sperm whale Kogia simus.
Pp.235-260 in (S. H. Ridgway and R. Harrison (eds.). Handbook
of marine mammals: river dolphins and the large toothed
whales. Academic Press, London.
Long, , D.
J. 1991. Apparent predation by a whale shark on Carcharodon
carcharias on a pygmy sperm whale Kogia breviceps.
Fisheiry Bulletin 538-540.
Reeves, R. R. B. S.
Stewart, P. J. Clapham and J. A. Powell. 2002. Guide to marine
mammals of the world. National Audubon Society, New York.
K. I. Marten, and T. W. Crawford. 1989. Pygmy sperm whale
sound Kogia breviceps. Pp. 59 in Abstracts of the 8th
Biennial Conferenc eon the Biology of Marinn Mammals. Pacific
Grove, CA, USA.
D. and J. G. Cordaro. 1987. Behavioral observations of the
dwarf sperm whale, Kogia simus. Marine Mammal Science