- Harbour Porpoise
name = Harbor PorpoiseMSW3 Cetacea|id=14300116]
status = LC
status_system = iucn3.1
status_ref =IUCN2008|assessors=Hammond, P.S., Bearzi, G., Bjørge, A., Forney, K., Karczmarski, L., Kasuya, T., Perrin, W.F., Scott, M.D., Wang, J.Y., Wells, R.S. & Wilson, B.|year=2008|id=17027|title=Phocoena phocoena|downloaded=7 October 2008]
image_width = 200px
image2_width = 250px
image2_caption = Size comparison against an average human
phylum = Chordata
genus = "
species = "P. phocoena"
binomial = "Phocoena phocoena"
binomial_authority = Linnaeus,
range_map_width = 250px
range_map_caption = Harbour Porpoise range
The Harbor Porpoise ("Phocoena phocoena") is one of six
speciesof porpoise. It is one of the smallest ocean mammals. As its name implies, it stays close to coastal areas or river estuaries and as such is the most familiar porpoise to whale watchers. This porpoise often ventures up rivers and has been seen hundreds of miles from the sea.
The species is sometimes known as the Common Porpoise in texts originating in the
United Kingdom, though this usage appears to be dying out.
The Harbor Porpoise is a little smaller than the other porpoises. It is about 67-85 cm (26-33 in) long at birth. Both sexes grow up to be 1.4 m to 1.9 m (4.6-6.2 ft). The females are correspondingly heavier, with a maximum weight of around 76 kg (167 pounds) compared with the males' 61 kg (134 pounds). The body is robust and the animal is at its maximum girth just in front of its triangular
dorsal fin. The beak is poorly demarcated. The flippers, dorsal fin, tail fin and back are a dark grey. The sides are a slightly speckled lighter grey. The underside is much whiter, though there are usually grey stripes running along the throat from the underside of their body.
Population and distribution
The species is widespread in cooler coastal waters in the Northern Hemisphere, largely in areas with a mean temperature of about 15°C. In the Atlantic, Harbour Porpoises may be present in a concave band of water running from the coast of western Africa round to the eastern seaboard of the
United States, including the coasts of Spain, France, the United Kingdom, Ireland, Norway, Iceland, Greenlandand Newfoundland. In prehistorictimes this animal was hunted by the Alby Peopleof the east coast of Oland, Sweden. There is a similarly-shaped band in the Pacific Ocean running from Sea of Japan, Vladivostok, the Bering Strait, Alaskaand down to Seattleand Vancouver. There are diminishing populations in the Black and Baltic Seas.
Prey and predators
Harbour Porpoises feed mostly on small fish, particularly
herring, capelin, and sprat. The deepest dive recorded was 224 m (735 ft) deep. Young porpoises need to consume about 7% to 8% of their body weight each day in order to survive.
Significant predators of Harbor Porpoises include white sharks and
orcas. Researchers at the University of Aberdeenin Scotlandhave also discovered that the local Bottlenose Dolphins attack and kill Harbour Porpoises without eating them due to competition for a decreasing food supply.cite book| author=Read, Andrew |title= "Porpoises"|year=1999|publisher=Voyageur Press |location=Stillwater, MN, USA|ISBN=0-89658-420-8]
Harbor Porpoises were traditionally hunted for food and especially fat used for lighting purposes in Denmark, especially in the
Little Beltstrait. Currently, however, this species is not subject to commercial whaling. The global population is in the hundreds of thousands and the Harbor Porpoise is not under threat of widespread extinction. However a key concern is the large number of porpoises caught each year in gill nets and other fishery equipment. This problem has led to a documented decrease in the number of Harbor Porpoises in busy fishing seas such as the Black and Baltic. It is known that the porpoises' echolocation is sufficiently discriminating to detect the presence of the nets Fact|date=March 2008, but this does not stop porpoises from becoming trapped. Scientists have developed beacons to attach to the nets to try to deter curious porpoises. These are not yet widespread and there is some controversy regarding their use—some concerns have been raised about the value of adding more noise pollution to the seas.
*ITIS|ID=180473|taxon=Phocoena phocoena|year=2006|date=18 March
*ARKive - [http://www.arkive.org/species/ARK/mammals/Phocoena_phocoena/ images and movies of the harbour porpoise "(Phocoena phocoena)"]
* [http://www.wdcs.org Whale & Dolphin Conservation Society (WDCS)]
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