Animal Diversity Web

Ge­o­graphic Range

Found in coastal re­gions of the North At­lantic, Arc­tic, and North Pa­cific Oceans; also the Mediter­ranean and Black Sea re­gions. They are found in bays, es­tu­ar­ies, river mouths, and some­times as­cend fur­ther up rivers. (Dollinger (ed­i­tor), 1988; Nowak, 1999; Dollinger (ed­i­tor), 1988; Nowak, 1999)

• Biogeographic Regions
• nearctic
  • native
• palearctic
  • native
• arctic ocean
  • native
• atlantic ocean
  • native
• pacific ocean
  • native
• mediterranean sea
  • native

• Other Geographic Terms
• holarctic

Habi­tat

Found in both salt and fresh water areas, Pho­coena pho­coena re­quire a shal­low coastal body of water. In the West­ern At­lantic, they also move far out to sea near the end of sum­mer and reap­pear in spring. Other re­gional pop­u­la­tions move south or far­ther away from shore to avoid ice buildups. (Nowak, 1999)

• Habitat Regions
• temperate
• polar
• saltwater or marine
• freshwater

• Aquatic Biomes
• pelagic
• rivers and streams
• coastal
• brackish water

• Other Habitat Features
• estuarine

Phys­i­cal De­scrip­tion

Pho­coena pho­coena, also known as the "Com­mon" or "Har­bor" Por­poise, is a small cetacean that is 1.5 to 2 me­ters long and weighs from 45 - 65 kilo­grams. The fe­male of the species is usu­ally slightly larger than the male. The color of the an­i­mal varies from in­di­vid­ual to in­di­vid­ual, but the most com­mon col­oration pat­tern is a dark dor­sal sur­face that shifts to a lighter col­ored hue ven­trally. Al­though the dark color is usu­ally black or deep gray, al­bi­nos have been re­ported in which the dark seg­ments are com­pletely or par­tially white. The flip­pers, dor­sal fin, and tail are all dark in color, and there is a black stripe that runs from the edge of the mouth or eye to the flip­per on ei­ther side. There is no no­tice­able fore­head or beak on this species, and the snout is short, giv­ing the head a some­what cone-like shape. P. pho­coena has two pec­toral flip­pers, a sin­gle dor­sal fin, and a tail with two par­tially sep­a­rated flukes. All of these ap­pendages are short and not very sharp, with the dor­sal fin being tri­an­gu­lar shaped and usu­ally around 15 - 20 cm tall. There is a no­tice­able keel lo­cated near the all dark tail flukes, with the tail it­self span­ning any­where from 30-65 cm. In­side the slightly up­turned mouth there are rows of 16-28 spade-shaped teeth. There is no vari­ance in the shape or type of teeth in P. pho­coena. (Dollinger (ed­i­tor), 1988; Nowak, 1999; The Por­poise Page, 1998)

• Other Physical Features
• endothermic
• bilateral symmetry

• Sexual Dimorphism
• female larger

• Range mass

  45 to 60 kg

  99.12 to 132.16 lb

• Range length

  1.5 to 2 m

  4.92 to 6.56 ft

• Average basal metabolic rate

  107.675 W

  AnAge

Re­pro­duc­tion

It is not clearly known how ex­ten­sive the mat­ing sea­son is in P. pho­coena, but it seems that mat­ing mainly oc­curs from June to Sep­tem­ber with births oc­cur­ring from May to Au­gust. It is com­monly noted that ges­ta­tion lasts 11 months with nurs­ing fol­low­ing for an­other 7 or 8 months. A fe­male will give birth to one calf per year, with the birth size of the calf being 6-8kg and 70-100cm long. Sex­ual ma­tu­rity is reached by the fifth year, if not be­fore, and the life span of P. pho­coena is be­lieved to be any­where from 6 to 20 years. (John­ston(1999), Nowak(1999))

• Key Reproductive Features
• iteroparous
• seasonal breeding
• gonochoric/gonochoristic/dioecious (sexes separate)
• sexual
• viviparous

• Breeding interval

  A female will give birth to one calf per year

• Breeding season

  Mating mainly occurs from June to September

• Average number of offspring

  1

• Average number of offspring

  1

  AnAge

• Average gestation period

  11 months

• Average gestation period

  320 days

  AnAge

• Range weaning age

  7 to 8 months

• Range age at sexual or reproductive maturity (female)

  5 (high) years

• Range age at sexual or reproductive maturity (male)

  5 (high) years

Lifes­pan/Longevity

• Average lifespan
  Status: wild

  13.0 years

  Max Planck Institute for Demographic Research

Be­hav­ior

The species usu­ally swims near the sur­face, ris­ing to the sur­face to breath about every 25 sec­onds. It does not pre­sent a very play­ful at­ti­tude, ig­nor­ing boats and rarely jump­ing out of the water. Har­bor Por­poises do not move par­tic­u­larly fast, but when pur­sued can reach speeds of around 23km/hr. When div­ing for food this por­poise stays down for an av­er­age of 4 min­utes, and is be­lieved to be able to dive as deep as 200m. Al­though schools of up to 100 in­di­vid­u­als may some­times be seen, P. pho­coena is usu­ally seen in pairs or in groups of 5-10. When the larger groups do occur, it is usu­ally be­cause a num­ber of smaller groups have joined to­gether while fol­low­ing a rich food source. Moth­ers bring new­born calves to se­cluded coves to nurse. Some pop­u­la­tions are known to mi­grate, but when they re­turn to their reg­u­lar wa­ters they are ter­ri­to­r­ial, pa­trolling cer­tain areas. (John­ston(1999), Nowak(1999))

• Key Behaviors
• natatorial
• motile
• migratory
• territorial
• social

Com­mu­ni­ca­tion and Per­cep­tion

• Perception Channels
• tactile
• chemical

Food Habits

Diet con­sists mainly of smooth, non-spiny fish, and cephalopods. Her­ring, pol­lack, hake, sar­dines, and cod are com­monly eaten. Other sea crea­tures such as squid and shrimp are also con­sumed. P. pho­coena pro­duces click-like sounds sim­i­lar to those used by other cetaceans as a means of echolo­ca­tion in order to lo­cate food.(John­ston(1999), Nowak(1999))

• Primary Diet
• carnivore
  • piscivore

• Animal Foods
• fish
• mollusks
• aquatic crustaceans

Eco­nomic Im­por­tance for Hu­mans: Pos­i­tive

Taken heav­ily in var­i­ous areas, the meat is used for human and an­i­mal con­sump­tion, and its oil is used in lamps and as a lu­bri­cant.

Con­ser­va­tion Sta­tus

Al­though fish­ing of P. pho­coena is now il­le­gal in most areas, the species is still in dan­ger. De­lib­er­ate and ac­ci­den­tal deaths still occur be­cause mod­ern fish­ing nets are al­most un­de­tectable to por­poises. Since these nets are com­monly used in nearshore areas, in the nat­ural range of P. pho­coena, they prob­a­bly kill large num­bers of por­poises. Var­i­ous mea­sures are being taken in the United States and other na­tions in an at­tempt to limit deaths of this kind. In ad­di­tion to deaths re­lated to fish­ing, por­poises also suf­fer from chem­i­cal and noise pol­lu­tion. (Dollinger(1988), John­ston(1999), McWilliam(1999), Nowak(1999))

• IUCN Red List

  Critically Endangered
  More information

• IUCN Red List

  Critically Endangered
  More information

• CITES

  Appendix II

Other Com­ments

One in­ter­est­ing dan­ger that the Har­bor Por­poise may be fac­ing is com­pletely nat­ural. As one group of re­searchers no­ticed, a num­ber of por­poise car­casses taken in Scot­land all had sim­i­lar punc­ture and bruise wounds, with most of them dying as a re­sult of in­ter­nal in­jury. In ad­di­tion to these in­juries some of the spec­i­mens also had teeth gouges in their flesh. After an­a­lyz­ing these bite pat­terns, the re­searchers de­ter­mined that the an­i­mal re­spon­si­ble for in­flict­ing these wounds was Tur­siops trun­ca­tus, the Bot­tlenosed Dol­phin. At least in this area of Scot­land it seems that where the two species' ranges over­lap, dol­phins are at­tack­ing and in some cases killing por­poises. It is not known for sure ex­actly what is prompt­ing this kind of be­hav­ior. (The Por­poise Page, 1998)

Con­trib­u­tors

George Ham­mond (), An­i­mal Di­ver­sity Web.

An­drew Masi (au­thor), Uni­ver­sity of Michi­gan-Ann Arbor, Phil Myers (ed­i­tor), Mu­seum of Zo­ol­ogy, Uni­ver­sity of Michi­gan-Ann Arbor.

Ref­er­ences

Dollinger (ed­i­tor), P. 1988. Con­ven­tion on In­ter­na­tional Trade in En­dan­gered Species of Wild Fauna and Flora; Iden­ti­fi­ca­tion Man­ual Vol I. Mam­malia. Switzer­land: Sec­re­tariat of the Con­ven­tion.

John­ston, D. 2001. "Har­bour Por­poise" (On-line). @​Phocoena.​org. Ac­cessed 11/03/04 at http://​phocoena.​org/​factsheets/​harbourporp.​html.

Nowak, R. 1999. Walker's Mam­mals of the World, 6th Ed. Vol II. Bal­ti­more: John Hop­kins Uni­ver­sity Press.

The Por­poise Page, 1998. "Har­bor Por­poise" (On-line). The Por­poise Page. Ac­cessed 11/03/04 at http://​www.​theporpoisepage.​com/​harbor.​php.