Spectacled porpoises are found only in the temperate and sub-Antarctic
waters of the Southern Hemisphere. Although the distribution
of spectacled porpoise in these waters is beleived to be circumpolar
in nature (see map), reliable sightings have only been made
at these locations: Heard Island, Kerguelan Island, Macquarie
Island, South Georgia, the Falkland Islands and Tierra del
Fuego. Spectacled porpoises appear to prefer cold (5.5 °
C to 9.5 ° C), open oceanic waters.
Spectacled porpoises are uniform black on their dorsal and
dorso-lateral surfaces which are separated from the lighter
ventral and ventro-lateral surfaces by a distinct line. They
have a black eyepatch which is usually outlined with white,
providing the basis for their common name (derived from the
Greek word diopter = spectacled). The dorsal fins of spectacled
porpoises are triangular in shape and are greatly enlarged
in males. Males are, in general, larger than females. Very
little is known about the ages of sexual maturity for this
species; based on a very small sample size it has been estimated
at around 4 years for males, and 2-3 years for females. Almost
nothing is known about the food preferences of spectacled
porpoises. A single stranded animal in Argentina had anchovy
and small crustaceans in its stomach.
There are no abundance estimates available for spectacled
porpoises and IUCN lists it as a Data Deficient species in
the Red List of Threatened Species.
Spectacled porpoises are taken in some fisheries including
gillnet fishereies in Tierra del Fuego and southeastern Chile.
They are also taken in some bottom and mid-water trawls in
Argentina. The magnitude of the above listed bycatch is not
Brownell Jr., & Clapham, P.J. 1999. Spectacled porpoise
(Phocoena dioptrica) In S.H. Ridgeway & R. Harrison [eds.],
Handbook of Marine Mammals, Volume 6: The Second Book of Dolphins
and Porpoises. Academic Press. San Diego.
Jefferson, T.A. et al. 1993. Marine Mammals of the World.
FAO Species Identification Guide. United Nations Environment
Perrin, W.F., Donovan, G.P. and Barlow, J. 1994. Gillnets
and Cetaceans. Report of the International Whaling Commission,
Special Issue 15. Cambridge.