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Lifespan, longevity, and ageing
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Maximum longevity: 22 years (wild) Observations: Average longevity is around 16-17 years (Margaret Klinowska 1991). Maximum longevity is probably underestimated.
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Reproduction
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Little is known about mating in cetaceans, especially in species which occur primarily offshore. Mating systems in Dall's porpoises are unknown.

Little is known about the reproductive biology of Dall's porpoises. Two calving periods have been reported for portions of the eastern North Pacific, one in winter, from February through March, and the other in summer, from July through August. Some segregation of animals seems to occur with juveniles found closer to shore and larger adults well offshore. In offshore areas, females in late pregnancy or lactation seem to be distributed in northern areas, and southern areas are mainly occupied by males and females not accompanied with calves. This seems to indicate that not all females become pregnant every year. Females usually reach sexual maturity between the age of 3 to 6 years, whereas males reach sexual maturity between the ages of 5 to 8 years. Gestation is believed to last about 11 months, and lactation periods are usually about 2 years.

Phocoenoides dalli dalli appear to have three major breeding grounds. Two occur in the North Pacific north of 45 degree latitude, and another breeding site occurs in the central Bering Sea. Phocoenoides dalli truei may breed off the northern coast of Japan.

Breeding interval: Individual females probably do not breed every year. Breeding intervals may be as long as 3 to 4 years because of the length of dependence of calves.

Breeding season: Mating is likely to occur after the calving seasons each year which occur in winter, from February to March, and in summer, from July to August.

Average gestation period: 11 months.

Average weaning age: 24 months.

Range age at sexual or reproductive maturity (female): 3 to 6 years.

Range age at sexual or reproductive maturity (male): 5 to 8 years.

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

Average gestation period: 347 days.

Average number of offspring: 1.

Females feed and care for their offspring for extended periods of time. It is likely that some form of extended learning occurs during this period as well. Male parents do not contribute parental care.

Parental Investment: no parental involvement; precocial ; pre-fertilization (Protecting: Female); pre-hatching/birth (Provisioning: Female, Protecting: Female); pre-weaning/fledging (Provisioning: Female, Protecting: Female); pre-independence (Provisioning: Female, Protecting: Female); extended period of juvenile learning

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Decker, J. 2002. "Phocoenoides dalli" (On-line), Animal Diversity Web. Accessed April 27, 2013 at http://animaldiversity.ummz.umich.edu/site/accounts/information/Phocoenoides_dalli.html
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Jeffrey Decker, University of Michigan-Ann Arbor
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Behavior
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As in most phocoenids, Dall's porpoises use a form of echolocation to navigate, capture prey, and perhaps to communicate with conspecifics. They also use a variety of audible clicks and whistles. They may also use touch for social communication.

Communication Channels: tactile ; acoustic

Perception Channels: visual ; tactile ; acoustic ; chemical

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Decker, J. 2002. "Phocoenoides dalli" (On-line), Animal Diversity Web. Accessed April 27, 2013 at http://animaldiversity.ummz.umich.edu/site/accounts/information/Phocoenoides_dalli.html
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Conservation Status
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Dall's porpoises are not directly exploited in the eastern Pacific, but serious conservation problems are centered in the western Pacific where, during the 1980's, Dall's porpoises were intensely hunted. Estimates suggested 40,367 Dall's porpoises were killed in 1989 from the Japanese hand-harpoon fishery alone. In recent years these numbers have declined because of the Japanese government's effort to regulate the hand-harpooning of these animals. In 1992 11,403 were killed. This species is often killed accidentally in the Japanese seas and off of North America by drift nets set for salmon. It has been estimated that up to 20,000 porpoises are entangled and drowned in these nets off of Japan and up to about 4,100 off of North America annually. Due to international negotiations between Japan and the United States, along with new fishing gear and techniques, the incidental take has been reduced drastically. However, the conservation of Dall's porpoises remains a major issue.

US Federal List: no special status

CITES: appendix ii

IUCN Red List of Threatened Species: least concern

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Decker, J. 2002. "Phocoenoides dalli" (On-line), Animal Diversity Web. Accessed April 27, 2013 at http://animaldiversity.ummz.umich.edu/site/accounts/information/Phocoenoides_dalli.html
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Benefits
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Dall's porpoises have no negative effects on humans.

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Decker, J. 2002. "Phocoenoides dalli" (On-line), Animal Diversity Web. Accessed April 27, 2013 at http://animaldiversity.ummz.umich.edu/site/accounts/information/Phocoenoides_dalli.html
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Jeffrey Decker, University of Michigan-Ann Arbor
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Benefits
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The only direct commercial harvest of Dall's porpoises is a traditional coastal harpoon fishery in Japan which accounts for annual harvests of about 6,000 animals to compensate for the shortage of whale meat. Dall's porpoises contribute to marine ecotourism through their gregariousness and their aquatic antics.

Positive Impacts: food ; ecotourism

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Decker, J. 2002. "Phocoenoides dalli" (On-line), Animal Diversity Web. Accessed April 27, 2013 at http://animaldiversity.ummz.umich.edu/site/accounts/information/Phocoenoides_dalli.html
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Associations
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Dall's porpoises are important predators of fish and cephalopods in the ecosystems in which they live.

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Decker, J. 2002. "Phocoenoides dalli" (On-line), Animal Diversity Web. Accessed April 27, 2013 at http://animaldiversity.ummz.umich.edu/site/accounts/information/Phocoenoides_dalli.html
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Jeffrey Decker, University of Michigan-Ann Arbor
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Trophic Strategy
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Dall's porpoises apparently feed at night and depend to some degree on the deep scattering layer, that is the fauna which travels upwards each night from the deeper parts of the ocean's water column. Food species as determined from stomach contents include squid and other cephalopods, lanternfish, Pacific hake, jack mackerel, herring, sardines, and crustaceans. Dall's porpoises are thought to be capable of deep diving because mesopelagic, bathypelagic, and deep-water benthic species are represented in the diet.

Animal Foods: fish; mollusks; aquatic crustaceans

Primary Diet: carnivore (Piscivore , Molluscivore )

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Decker, J. 2002. "Phocoenoides dalli" (On-line), Animal Diversity Web. Accessed April 27, 2013 at http://animaldiversity.ummz.umich.edu/site/accounts/information/Phocoenoides_dalli.html
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Distribution
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Dall's porpoises, Phocoenoides dalli, are cool water porpoises inhabiting the North Pacific Ocean and adjacent seas. The central Bering Sea marks the northern boundary of their range and, although they prefer colder water, Dall's porpoises are found in the warmer waters of Baja California on the east to southern Japan on the west. They are frequently observed in these lower latitudes during the winter months. There are potentially two subspecies of Dall's porpoises, although they may simply be color morphs, P. dalli dalli and P. dalli truei. Phocoenoides dalli truei is abundant only off the Pacific coast of northern Japan.

Biogeographic Regions: pacific ocean (Native )

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Decker, J. 2002. "Phocoenoides dalli" (On-line), Animal Diversity Web. Accessed April 27, 2013 at http://animaldiversity.ummz.umich.edu/site/accounts/information/Phocoenoides_dalli.html
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Habitat
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Generally the colder waters of the North Pacific are home to Dall's porpoises. They are observed inshore and offshore. They are a deep water species, so when they approach the coast they usually follow canyons or deep channels. They are also commonly observed in sounds and inland passages where these meet the open sea.

Habitat Regions: temperate ; polar ; saltwater or marine

Aquatic Biomes: pelagic ; coastal

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Decker, J. 2002. "Phocoenoides dalli" (On-line), Animal Diversity Web. Accessed April 27, 2013 at http://animaldiversity.ummz.umich.edu/site/accounts/information/Phocoenoides_dalli.html
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Life Expectancy
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The average lifespan of a Dall's Porpoise is 16-17 years.

Average lifespan
Status: wild:
16-17 years.

Average lifespan
Status: wild:
22.0 years.

Average lifespan
Status: wild:
17.0 years.

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Decker, J. 2002. "Phocoenoides dalli" (On-line), Animal Diversity Web. Accessed April 27, 2013 at http://animaldiversity.ummz.umich.edu/site/accounts/information/Phocoenoides_dalli.html
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Morphology
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Dall's porpoises are the largest of the phocoenids. They typically reach a length of 1.8 to 2.0 meters, rarely more than 2.2 meters. At birth, the length is between 0.85 and 1.0 meters. Weight in adults varies from 130 to 220 kilograms. The body is stocky and more powerful than other members of Phocoenidae. The head is small and lacks a beak although there is a sloping forehead. The flippers are small, pointed, and located near the head. The dorsal fin is triangular in shape with a hooked tip.

There are three color patterns observed in the Dall's porpoises. The first is a uniform black or white throughout the entire body. The second pattern consists of intermixed stripes of black and white running along the length of the body. Finally, there is the most common color pattern observed, that of P. dalli dalli. This is defined as having a dorsal area uniformly black with a white ventral side. The white ventral patch begins far behind the flippers. The dorsal fin, flippers, and fluke are black with some white at the tips. The color pattern of P. dalli truei is different only in the distribution of the white ventral patch. The white patch begins ahead of the flippers rather than far behind them, and P. dalli truei is often longer and slimmer than P. dalli dalli.

Range mass: 130 to 220 kg.

Range length: 2.2 (high) m.

Average length: 1.8-2.0 m.

Other Physical Features: endothermic ; homoiothermic; bilateral symmetry ; polymorphic

Sexual Dimorphism: sexes alike

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Decker, J. 2002. "Phocoenoides dalli" (On-line), Animal Diversity Web. Accessed April 27, 2013 at http://animaldiversity.ummz.umich.edu/site/accounts/information/Phocoenoides_dalli.html
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Associations
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Killer whales and sharks are believed to be the primary natural predators of Dall's porpoises. They largely escape predation through their large body size, agility in the water, and their habit of traveling in groups. Their coloration may make them difficult to see in the water as well.

Anti-predator Adaptations: cryptic

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Decker, J. 2002. "Phocoenoides dalli" (On-line), Animal Diversity Web. Accessed April 27, 2013 at http://animaldiversity.ummz.umich.edu/site/accounts/information/Phocoenoides_dalli.html
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Diagnostic Description
provided by FAO species catalogs
These are robust animals, with a wide-based triangular dorsal fin, and small flippers placed near the head. The small head has a short beak, with no demarcation from the melon. From above, the head appears triangular.

Dall's porpoises are strikingly marked, with a black body and bright white flank patches that are continuous ventrally, although young animals have muted colour patterns. The flank patches extend from the urogenital area to just in front of the dorsal fin, and up the sides about midway. In addition, there is white to light grey "frosting" on the upper portion of the dorsal fin and the trailing edges of the flukes. There are 2 commonly occurring colour types, the dalli-type (described and illustrated above) and the truei-type (which has a larger flank patch that extends to the level of the flipper).

Dall's porpoise has the smallest teeth of any cetacean. There are 23 to 28 tiny spade-shaped teeth in each tooth row.

Can be confused with: Dall's porpoises are likely to be confused only with harbour porpoises, and even then, only if seen at a great distance. When seen well, the differences in colour pattern and dorsal-fin shape will be readily apparent.

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Marine mammals of the world. Jefferson, T.A., S. Leatherwood & M.A. Webber - 1993. FAO species identification guide. Rome, FAO. 320 p. 587 figs. . 
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Size
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Newborn Dall's porpoises are about 1 m long. Adults are up to 2.2 m (females) or 2.4 m (males). Maximum weight is about 200 kg.
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Marine mammals of the world. Jefferson, T.A., S. Leatherwood & M.A. Webber - 1993. FAO species identification guide. Rome, FAO. 320 p. 587 figs. . 
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Brief Summary
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This may be the fastest swimmer of all small cetaceans, at least for short bursts. When swimming rapidly, Dall's slice along the surface, producing a characteristic roostertail of spray. At other times, the animals move slowly and roll at the surface, creating little or no disturbance. These are avid bowriders, moving back and forth with jerky movements, and often coming from seemingly nowhere to appear at the bow of a fast-moving vessel. Breaching, porpoising, and other kinds of aerial behaviour, are extremely rare in this species. Dall's porpoises are found mostly in small groups of 2 to 12, although aggregations of up to several thousand have been reported. Groups appear to be fluid, often forming and breaking up for feeding and playing. Most Dall's porpoise calves are born in spring and summer.

Dall's porpoises are opportunistic feeders, taking a range of surface and mid-water fish and squid, especially lanternfish and gonatid squid.

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Marine mammals of the world. Jefferson, T.A., S. Leatherwood & M.A. Webber - 1993. FAO species identification guide. Rome, FAO. 320 p. 587 figs. . 
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Benefits
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Conservation Status : The International Whaling Commission currently recognizes 8 stocks, based on pollutant loads, parasite faunas, and distribution patterns of cow-calf pairs. Heavy exploitation occurs in the western Pacific, both in a directed harpoon fishery and in several gillnets fisheries, in which Dall's are caught incidentally. The Asian driftnet fisheries for squid and salmon took several thousand anually in recent years in the central Pacific. Although there are records of small numbers being taken incidentally in the eastern Pacific, stocks there, unlike those in the central and western Pacific, are supposedly not in any immediate danger. IUCN:

Insufficiently known.

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Marine mammals of the world. Jefferson, T.A., S. Leatherwood & M.A. Webber - 1993. FAO species identification guide. Rome, FAO. 320 p. 587 figs. . 
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Dall's porpoise
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Dall's porpoise (Phocoenoides dalli) is a species of porpoise found only in the North Pacific. It came to worldwide attention in the 1970s when it was disclosed for the first time to the public that salmon fishing trawls were killing thousands of Dall's porpoises and other cetaceans each year by accidentally capturing them in their nets. Dall's porpoise is the only member of the genus Phocoenoides. It was named after American naturalist W. H. Dall.

Description

 src=
Dorsal view of a Dall's porpoise

The body shape of Dall's porpoise makes it easily distinguishable from other cetacean species. The animal has a very thick body and a small head. The colouration is rather like that of a killer whale; the main body of the porpoise is very dark grey to black, with very demarcated white patches on the flank and belly. The dorsal fin is set just back from the middle of the back and sits up erect. The upper part of the dorsal fin has a white to light grey "frosting".

The fluke has a similar frosting. The adult fluke curves back towards the body of the animal, which is another distinguishing feature. It is larger than other porpoises, growing up to 2.3 m (7.5 ft) in length and weighing between 130 and 220 kg (290 and 490 lb).[3] There is also sexual dimorphism in the species, with males being larger, having a deeper caudal peduncle and a pronounced hump behind the anus.[3] Young Dall's have a greyish tint and dark-colored flukes.

Population and distribution

 src=
A Dall's porpoise on a calm day in the Shelikof Strait

Dall's porpoise ranges through much of the North Pacific and nearby seas, such as the Bering and Okhotsk Seas and the Sea of Japan. The southernmost part of its range is southern Japan in the west and southern California in the east, while it is northernmost range is the central Bering Sea.[4] They do enter Scammon's Lagoon in Baja California, though, when the waters are unseasonably cold.[5] They also travel up to the Chukchi Sea, though very rarely.[4]

Dall's porpoise prefers cold waters more than 180 metres (590 ft) deep.[3] It is found over the continental shelf adjacent to the slopes and oceanic waters.[6] While it mostly lives in offshore waters, it does occur in deep coastal waters off North America.[4] There, it typically stays close to deep-water canyons.

Two consistent and well-defined colour morphs, the dalli-type and the truei-type, have been identified. The dalli-type is present throughout the porpoise's range, while the truei-type lives mostly on the western Pacific and is rare in the east.[3] There is some question as to whether the morphs are merely colour patterns (the truei-type having a more extensive belly patch) or whether they are separate subspecies.[5][7] They are believed to number around 104,000 off Japan, 554,000 in the Okhotsk Sea, 83,000 off Alaska and 100,000 off the continental US.[4]

Ecology and lifestyle

 src=
Dall's porpoise in Prince William Sound causing a "rooster tail"

Dall's porpoises primarily eat small fish and cephalopods.[4] Schooling fish, such as herrings, anchovies, pilchards, mackerels, hake and sauries are favored prey,[3][4] as well as mesopelagic fish such as myctophids and deep sea smelts.[4] They may also consume krill, but these are probably not important in their diet.[4] Dall's porpoise are deep divers. They have been recorded diving to 94 m.[8] Dall's porpoise are prey to killer whales and great white sharks.[9] However, Saulitis et al. (2000) described non-aggressive interactions between killer whales and Dall's porpoises in Prince William Sound, reporting that "Dall's porpoises were observed swimming with resident killer whales, engaging in apparent play behaviors with killer whale calves, and surfacing rapidly just in front of killer whales, sometimes making physical contact...One recognizable Dall's porpoise remained with the AB resident pod from May through September in 1984".[10]

 src=
A group of Dall's porpoises near Point Reyes

Dall's porpoises are highly active. They will often zigzag around at great speed on or just below the water surface, creating a spray called a "rooster tail". They may appear and disappear quite suddenly. The fastest of all small cetaceans, Dall's porpoises can swim at up to 55 km/h, almost as fast as the killer whale. The porpoises will approach boats and will bow- and stern-ride, but may lose interest, unless the boat is travelling quickly. They will also "snout ride" on waves made by the heads of large whales.[4] They may also exhibit calmer behavior, such as subdued rolls at the surface.[4] They rarely leap from the water.[4] Dall's Porpoises have never been observed to sleep.[11]

Dall's porpoises live in small, fluid groups of two to 12.[3] However they can gather in the hundreds when feeding.[3] They have a polygynous mating system in which males will guard females in estrus.[12] During the mating season, a male will select a fertile female and guard her to ensure that he will sire her calf.[12] While guarding, males may sacrifice opportunities to forage in deep dives.[12] Births usually take place in the summer.[4] Porpoise gestation lasts 10 to 11 months, and the lactation period lasts at least two months.[3] Depending on their condition, females can give birth up to every year.[3] Dall's porpoises live for up to 22 years.[13]

 src=
Dall's porpoises at market in Japan

They are susceptible to certain parasites. The trematode fluke Nastitrema, an internal parasite, is known to cause death and stranding of the porpoises.[4] External parasites of the porpoise are whale lice.

One study determined through DNA sequencing that a fetus found in British Columbia was an intergeneric hybrid of a Dall's porpoise and a harbour porpoise. This hybrid may not be rare— it may describe the origins of some atypically coloured individuals that otherwise appear to be Dall's porpoises spotted off the coast of Vancouver Island.[14]

Conservation status

Many Dall's porpoises are killed each year as by-catch in fishing nets.[citation needed] A serious cause of concern is the hunting of the species by harpoon by Japanese hunters.[citation needed] The number of porpoise caught each year rose dramatically following the moratorium on hunting larger cetaceans introduced in the mid-1980s. The greatest number were caught in 1988, when more than 40,000 were taken. International attention to the hunt through a 1990 International Whaling Commission (IWC) resolution resulted in a reduction in numbers caught; however, around 15,000 animals are still caught each year, making it the largest direct hunt of any cetacean species in the world. The hunt has been repeatedly criticized by the IWC and its Scientific Committee, most recently in 2008.[15] A quota of just over 16,000 individuals per year is now in effect. In addition, unknown numbers of animals are struck and lost or caught as by catch. Despite these threats, Dall's porpoise remains a fairly common species with productive populations.

Dall's porpoise is listed on Appendix II[16] of the Convention on the Conservation of Migratory Species of Wild Animals (CMS). It is listed on Appendix II[16] as it has an unfavorable conservation status or would benefit significantly from international co-operation organized by tailored agreements.

See also

References

  1. ^ Mead, J.G.; Brownell, R. L. Jr. (2005). "Order Cetacea". In Wilson, D.E.; Reeder, D.M. Mammal Species of the World: A Taxonomic and Geographic Reference (3rd ed.). Johns Hopkins University Press. pp. 723–743. ISBN 978-0-8018-8221-0. OCLC 62265494..mw-parser-output cite.citation{font-style:inherit}.mw-parser-output q{quotes:"""""'"'"}.mw-parser-output code.cs1-code{color:inherit;background:inherit;border:inherit;padding:inherit}.mw-parser-output .cs1-lock-free a{background:url("//upload.wikimedia.org/wikipedia/commons/thumb/6/65/Lock-green.svg/9px-Lock-green.svg.png")no-repeat;background-position:right .1em center}.mw-parser-output .cs1-lock-limited a,.mw-parser-output .cs1-lock-registration a{background:url("//upload.wikimedia.org/wikipedia/commons/thumb/d/d6/Lock-gray-alt-2.svg/9px-Lock-gray-alt-2.svg.png")no-repeat;background-position:right .1em center}.mw-parser-output .cs1-lock-subscription a{background:url("//upload.wikimedia.org/wikipedia/commons/thumb/a/aa/Lock-red-alt-2.svg/9px-Lock-red-alt-2.svg.png")no-repeat;background-position:right .1em center}.mw-parser-output .cs1-subscription,.mw-parser-output .cs1-registration{color:#555}.mw-parser-output .cs1-subscription span,.mw-parser-output .cs1-registration span{border-bottom:1px dotted;cursor:help}.mw-parser-output .cs1-hidden-error{display:none;font-size:100%}.mw-parser-output .cs1-visible-error{font-size:100%}.mw-parser-output .cs1-subscription,.mw-parser-output .cs1-registration,.mw-parser-output .cs1-format{font-size:95%}.mw-parser-output .cs1-kern-left,.mw-parser-output .cs1-kern-wl-left{padding-left:0.2em}.mw-parser-output .cs1-kern-right,.mw-parser-output .cs1-kern-wl-right{padding-right:0.2em}
  2. ^ Hammond, P.S., Bearzi, G., Bjørge, A., Forney, K.A., Karkzmarski, L., Kasuya, T., Perrin, W.F., Scott, M.D., Wang, J.Y. , Wells, R.S. & Wilson, B. (2012). Phocoenoides dalli. The IUCN Red List of Threatened Species doi:10.2305/IUCN.UK.2012.RLTS.T17032A17118773.en
  3. ^ a b c d e f g h i Randall R. Reeves; Brent S. Stewart; Phillip J. Clapham; James A. Powell (2002). National Audubon Society Guide to Marine Mammals of the World. Alfred A. Knopf, Inc. ISBN 0375411410.
  4. ^ a b c d e f g h i j k l m Jefferson, Thomas A. (2008). "Dall's porpoise Phocoenoides dalli", pp. 296–298 in Encyclopedia of Marine Mammals, William F. Perrin, Bernd Wursig, and J. G.M. Thewissen (eds.), Academic Press; 2nd ed..
  5. ^ a b Morejohn, G. Victor (1979). "The Natural History of Dall's Porpoise in the North Pacific Ocean". In Winn, H.E.; Olla, B.L. Behavior of Marine Animals. 3 "Cetaceans". pp. 45–83. doi:10.1007/978-1-4684-2985-5_3. ISBN 978-1-4684-2987-9.
  6. ^ Hall, J. (1979). A survey of cetaceans of Prince William Sound and adjacent waters – their numbers and seasonal movements. Unpubl. rep. to Alaska Outer Continental Shelf Environmental Assessment Programs. NOAA OCSEAP Juneau Project Office, Juneau, AK.
  7. ^ Escorza-Treviño, S.; Pastene, L. A.; Dizon, A. E. (2004). "Molecular Analyses of the Truei and Dalli Morphotypes of Dall's Porpoise (Phocoenoides dalli)". Journal of Mammalogy. 85 (2): 347. doi:10.1644/1545-1542(2004)085<0347:MAOTTA>2.0.CO;2.
  8. ^ Hanson, M.B.; Baird, R.W. (1998). "Dall's porpoise reactions to tagging attempts using a remotely-deployed suction-cup attached tag". Marine Technology Society Journal. 32 (2): 18–23.
  9. ^ Deecke, V. B.; Ford, J.K.; Slater, P. J. (2005). "The vocal behaviour of mammal-eating killer whales: communicating with costly calls". Animal Behaviour. 69 (2): 395–405. doi:10.1016/j.anbehav.2004.04.014.
  10. ^ Saulitis, Eva; Matkin, Craig; Barrett-Lennard, Lance; Heise, Kathy; Ellis, Graeme (2000). "Foraging Strategies of Sympatric Killer Whale (Orcinus orca) Populations in Prince William Sound, Alaska" (PDF). Marine Mammal Science. 16: 94. doi:10.1111/j.1748-7692.2000.tb00906.x.
  11. ^ Ridgway, S.H.; Harrison, R.J. (1999). Handbook of Marine Mammals: The Second Book of Dolphins and the Porpoises. Academic Press. p. 452. ISBN 9780125885065.
  12. ^ a b c Willis, Pamela M.; Dill, Lawrence M. (2007). "Mate Guarding in Male Dall's Porpoises (Phocoenoides dalli)" (PDF). Ethology. 113 (6): 587. doi:10.1111/j.1439-0310.2007.01347.x.
  13. ^ "Dall's Porpoise – Phocoenoides Dalli". United States National Park Service.
  14. ^ Baird, Willis; Guenther, Wilson (1998). "An intergenetic breed in the family Phocoenoidae". Canadian Journal of Zoology. 76: 198–204. doi:10.1139/z97-175a.
  15. ^ "Report of the Sub-Committee on Small Cetaceans" (PDF). 7.6: International Whaling Commission. June 2008. p. 10. Retrieved 2010-03-01.
  16. ^ a b "Appendix II Archived 11 June 2011 at the Wayback Machine." of the Convention on the Conservation of Migratory Species of Wild Animals (CMS). As amended by the Conference of the Parties in 1985, 1988, 1991, 1994, 1997, 1999, 2002, 2005 and 2008. Effective: 5 March 2009.

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Dall's porpoise: Brief Summary
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Dall's porpoise (Phocoenoides dalli) is a species of porpoise found only in the North Pacific. It came to worldwide attention in the 1970s when it was disclosed for the first time to the public that salmon fishing trawls were killing thousands of Dall's porpoises and other cetaceans each year by accidentally capturing them in their nets. Dall's porpoise is the only member of the genus Phocoenoides. It was named after American naturalist W. H. Dall.

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Habitat
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in deep waters, warm temperate to subarctic
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van der Land, J. (ed). (2008). UNESCO-IOC Register of Marine Organisms (URMO). IUCN (2008) Cetacean update of the 2008 IUCN Red List of Threatened Species.
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Jacob van der Land [email]
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WoRMS:note:134450
IUCN Red List Category
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Least Concern (LC)
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bibliographic citation
van der Land, J. (ed). (2008). UNESCO-IOC Register of Marine Organisms (URMO). IUCN (2008) Cetacean update of the 2008 IUCN Red List of Threatened Species.
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Perrin, William [email]
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WoRMS:note:137478