Lagenorhynchus albirostris
The white-beaked dolphin is dark grey to black dorsally, with
a lighter "saddle patch" just behind the dorsal
fin. There is a dark grey-white blaze from above the eye,
across the flanks to the anal arae. The rostrum is white to
light-grey. The body is very stocky and torpedo-shaped. The
beak is rather short and the flippers are broad. The dorsal
fin is tall and sickle-shaped. The tail stock is very thick.
The adult white-beaked dolphin is 2.5-2.7 m long and weighs
about 180 kg (maximum: 3 m and 275 kg (Peet et al, 1992)).
They have 22-28 pairs of small sharp-pointed teeth in each
jaw. They are fast swimmers, often creating so-called "rooster
tails" of water, like Dall's porpoises do.
The white-beaked dolphin can be found in the temperate and
sub-polar waters of the North Atlantic. They usually swim
in small groups of 6-10 animals, but occassionally aggregate
in groups of up to 1,500 animals (Minasian et al (1984, Klinowska
(1991)). They occassionally mix with Atlantic white-sided
dolphin groups.
Calves are born between June and September. At birth they
are about 115 cm long and weigh 40 kg. They reach sexual maturity
at a length of 1.95 m.
Very little is known about this species. They are common off
Cape Cod in spring and seasonally abundant near Greenland
and the Faeroe Islands. They are probably the most common
dolphin in Icelandic waters and in the North Sea.
This species has been exploited on a low level for some time
in Norway and the Barents Sea and around Iceland(Mitchell,
1975). There may still be a small take of this species in
Greeland and the Faeroe Islands. It is also by-caught in gillnet
fisheries, but the number of dolphins killed in these fisheries
is unknown (Read (1994), IWC (1996)). A bycatch of 45 animals
was reported for the Netherlands fisheries in 1994 (IWC, 1996).
To date there has been only one animals kept in captivity
at the (now defunct) Dolfirama in Zandvoort, the Netherlands.
This animal was live stranded in July 1982. It was transported
to a facility in Germany in 1983, where it died the same year
(Peet et al, 1992). A number of animals have been housed temporarily
in rehabilitation facilities in Mystic, Boston and Harderwijk,
after being stranded.
Van Bree and Nijssen(1964) found the otoliths of cod, haddock,
herring and plaice in the stomachs of stranded animals. Squid,
octopus and small crustaceans are also part of their diet.
van Bree, P.J.H and Nijssen, H. (1964)
On three specimens of Lagenorhynchus albirostris Gray, 1846
(Mammalia, Cetacea). Beaufortia 11(139):85-93
Evans, P.G.H. (1987)
The natural history of whales and dolphins. Christopher Helm,
London.
International Whaling Commission (1996)
Report of the sub-committee on small cetaceans. Rep. Int.
Whal. Commn. 46:160-179
Klinowska, M. (1991)
Dolphins, Porpoises and Whales of the World. The IUCN Red
Data Book. IUCN, Gland, Switzerland.
Minasian, S.M., Balcomb III, K.C. and Foster, L. (1984)
The world's whales. The complete illustrated guide. Smithsonian
Books, Washington D.C.
Mitchell, E. (1975)
Porpoise, dolphin and small whale fisheries of the world.
Status and problems. IUCN Monograph No. 3. IUCN, Gland, Switzerland
Peet, G., Nijkamp, H., Nelissen, P.-H. and Maas, F.-J. (1992)
Bruinvissen dolfijnen en walvissen van de Noordzee. Uitgeverij
M&P, Weert, the Netherlands.
Read, A.J. (1994)
Interactions between cetaceans and gillnet and trap fisheries
in the Northwest Atlantic. In: W.F. Perrin, G.P. Donovan and
J. Barlow (eds.): Gillnets and cetaceans. Rep. Int. Whal.
Commn. (Special Issue 15):133-147 (SC/O90/G6)
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