Lagenorhynchus obscurus
The Dusky Dolphin (Lagenorhynchus obscurus), belongs to the
Delphinidae Family which includes all dolphin species. Its
length does not exceed 2.1 meters and it can reach 90 kg in
weight.
It is often mistaken for the Peale's Dolphin (Lagenorhynchus
australis), but it is possible to distinguish between them
by observance of the the Dusky Dolphin's white grayish band
on both sides that forms two forward pointing blazes. Also,
the Dusky Dolphin has a lighter colored face, whereas the
Peale's Dolphin's face is dark, and the posterior part of
its fin is light colored.
Its habitat is limited to the the Southern Hemisphere, and
the Dusky Dolphin can be observed in South America, New Zealand,
the Kerguelen Islands (in the Indic Ocean) and South Africa.
In South America, it is most commonly found between the Península
Valdés and the Province of Buenos Aires in the Atlantic
Ocean and from Valparaíso (Chile) to Peru in the Pacific
Ocean.
It is a highly gregarious species and lives in coastal areas.
It is extremely acrobatic, leaping over 4 meters high, and
has been observed repeating these jumps various times (up
to 15 consecutive leaps). These leaps are either of a headfirst
reentry or salmon leaps (This type of leaps are named as "salmon
leaps" because when the dolphin performs these kind of
breaches, it reminds of a salmon making leaps in the water.).
Dusky Dolphins are seen associated with other cetacean species
such as the Southern Right Whale and Common Dolphin, as well
as with the Southern sea Lion and various species of birds.
Dusky Dolphin has been captured accidentally in fishing nets.
Fundación Cethus has participated of a Pilot Project
to study this species of dolphin in Golfo Nuevo, Península
Valdés, at the end of 1998 and the begining of 1999.
The responsible researches of this project were: Bernd Würsig
(Marine Mammal Research Program, Texas A&M University,
USA); Kathleen Dudzinski (Faculty of Bioresources, Mie University,
Japan) and Alejandro Acevedo (Institute of Marine Sciences,
University of California, USA).
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