Porpoise (Various)

 

Class: Mammalia
Order: Cetacea
Family:    Phocoenidae
Size:    Length: 4 to 7.5 feet (1.22 to 2.2 m)
Weight: 50 to 350 pounds (23 to 159 kg)
Diet: Fish, including herring, cod, sardines, shrimp and squid
Distribution: Oceans and seas around the world
Young:  1 calf
Animal Predators:  Killer whales and sharks
IUCN Status: See Conservation below
Terms: Young: Calf
Lifespan: 8 to 20 years in the wild, less in captivity

 

Facts/Trivia:

        The Dallís porpoise is the fastest porpoise, swimming at speeds of up to 35 miles (56 km) per hour.

        Some people refer to dolphins as porpoises, but they are distinctly different animals.

        The harbour porpoise is also referred to as the common porpoise.

        The harbour porpoise has been protected under the Canada Fisheries Act since 1982.

Description

There are six species of porpoises in the world. Three are black with white markings, while the Burmeisterís porpoise is dark brown all over and the harbour porpoise is dark grey or brown with a lighter grey flank. The finless porpoise is grey with a lighter throat and face area, and is the only porpoise with no dorsal fin. Porpoises are related to both whales and dolphins, but porpoises are smaller. Porpoises have a chubbier shape and a blunt snout, unlike the dolphin, which is streamlined and has a pronounced beak. Porpoises also have spade-shaped teeth, whereas dolphins have cone-shaped teeth. Female porpoises are usually larger than male porpoises. 

 

Habitat

Harbour porpoises stay in the cool waters of the northern hemisphere, off the coast of Europe, North America and Asia, while California Gulf porpoises live in the warmer waters of the Gulf of California, the Gulf of Guinea and the Black Sea. Spectacled porpoises frequent the western coast of South America and the Falkland and South Georgia islands. Dallís porpoises, the most active and sociable porpoises, live in the North Pacific south to Japan, as well as off the west coast of North America. Finless porpoises inhabit the Indo-Pacific Ocean off southern and eastern Asia.

 

Feeding Habits

All porpoises have a fish diet, but certain species have preferences. Harbour porpoises prefer herring, cod and sardines, while Dallís porpoises will fill up on squid when it is available.

 

Reproduction

Porpoises mate during the summer months, and a single calf is born approximately 11 months later. The calf is approximately half the length of its mother, and swims to the surface immediately after birth to get its first breath. The female swims on her side while her baby is nursing. The calf nurses from six months to two years, depending on the species. 

 

Behaviour

Porpoises live in large groups, sometimes comprised of more than one thousand individuals, but usually up to 20. 

 

Conservation

Several species of porpoises are listed with the IUCNís Red List. The harbour porpoise (phocoena phocoena) is listed as Vulnerable; the Yangtze River population of the finless porpoise (neophocaena phocaenoides) is listed as Endangered; the California Gulf porpoise (phocoena sinus) is Critically Endangered; and the Dallís porpoise (phocoenides dalli) is listed as Lower Risk, Conservation Dependent.

 

Sources

http://animaldiversity.ummz.umich.edu/accounts/phocoendoides/p._dalli$narrative.html

http://www.theporpoisepage.com/

http://ourworld.compuserve.com/homepages/jaap/phocoena.htm

http://www.imma.org/porpoise.html

http://www.cetacea.org/porpoise.htm

http://mbgnet.mobot.org/salt/animals/porpoise.htm

http://phocoena.org/factsheets/finless.html

http://www.bcadventure.com/adventure/wilderness/animals/dallporp.htm

http://www.nhm.org/research/mammals/dolporp/dolporp.html

http://animaldiversity.ummz.umich.edu/accounts/neophocaena/n._phocaenoides$narrative.html

http://animaldiversity.ummz.umich.edu/accounts/australophocoena/a._dioptrica$narrative.html

http://animaldiversity.ummz.umich.edu/accounts/phocoena/p._phocoena$narrative.html#physical_characteristics

http://animaldiversity.ummz.umich.edu/accounts/phocoena/p._spinipinnis$narrative.html#geographic_range

Porpoise Wildlife Fact File, IM Pub, US