Overview

Distribution

occurs (regularly, as a native taxon) in multiple nations

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National Distribution

Canada

Origin: Native

Regularity: Regularly occurring

Currently: Present

Confidence: Confident

Type of Residency: Year-round

United States

Origin: Native

Regularity: Regularly occurring

Currently: Present

Confidence: Confident

Type of Residency: Year-round

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Global Range: Small coastal streams from the Eel River, Humboldt County, California, north to the Prince William Sound area, Alaska, including numerous islands with suitable habitat off the coast of British Columbia and southern Alaska (Moyle et al. 1989, Behnke 1992). Typically does not occur farther inland than about 150 km (Behnke 1992). Both sea-run and anadromous stocks occur throughout the range. This is the most widely distributed and abundant subspecies of cutthroat trout, though its "abundance" is only relative to the other depleted subspecies (Behnke 1992). See Moyle et al. (1989) for details on distribution in California.

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Humboldt River drainage, Nevada and Oregon, U.S.A.
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Eastern North Pacific, introduced elsewhere.
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Physical Description

Size

Length: 38 cm

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Maximum size: 990 mm TL
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Diagnostic Description

Differs from all other trout by its densely packed profusion of small to medium-sized spots of irregular (not round) shape, which are distributed more or less evenly over the sides of the body, onto the head, and often onto the ventral surface and anal fin, though in sea-run individuals silvery skin deposits often obliterate or mask body spots (Benhke 1992). Does not develop the brilliant colors of some interior subspecies (Behnke 1992).

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Ecology

Habitat

Habitat Type: Freshwater

Comments: Requires small, low gradient coastal streams and estuarine habitats; well-shaded streams with water temperatures below 18 C are optimal (Moyle et al. 1989). Some may spend entire life in freshwater (many of these live in lakes), but most are anadromous (summer in saltwater). In summer, most individuals in streams are of the first-year age class; a few may be older nonanadromous fish and anadromous fish landlocked by rapidly receding water levels (Moyle et al. 1989). In marine habitats, generally remains close to the coast, usually remaining within estuary.

Spawns in streams on clean, small gravel substrates; females dig multiple redds, cover eggs after spawning. After emerging, fry move into larger rivers (or lakes), migrate to sea during their first year (or sometimes in second or third year) (Moyle et al. 1989).

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Depth range based on 3 specimens in 1 taxon.

Environmental ranges
  Depth range (m): 0.385 - 2.5

Graphical representation

Depth range (m): 0.385 - 2.5
 
Note: this information has not been validated. Check this *note*. Your feedback is most welcome.

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Migration

Non-Migrant: Yes. At least some populations of this species do not make significant seasonal migrations. Juvenile dispersal is not considered a migration.

Locally Migrant: Yes. At least some populations of this species make local extended movements (generally less than 200 km) at particular times of the year (e.g., to breeding or wintering grounds, to hibernation sites).

Locally Migrant: Yes. At least some populations of this species make annual migrations of over 200 km.

Migratory and nonmigratory stocks occur throughout the range (Behnke 1992). In northern California, begins to migrate up streams in September-October, following the first heavy rains; migrates up to 70-90 km inland in the Smith River, not so far in streams to the south (Moyle et al. 1989).

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Trophic Strategy

Comments: Adults eat insects, crustaceans, and other fishes. Young feed mostly on aquatic and drift insects, microcrustaceans, and occasionally smaller fishes. (Moyle et al. 1989).

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Population Biology

Number of Occurrences

Note: For many non-migratory species, occurrences are roughly equivalent to populations.

Estimated Number of Occurrences: 81 to >300

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Global Abundance

10,000 to >1,000,000 individuals

Comments: In California, probably always has been uncommon.

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General Ecology

As evidenced by indicative scarring, predation at sea may be a significant cause of natural mortality (see Behnke 1992).

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Life History and Behavior

Reproduction

Main time of spawning typically is late winter or early spring, though May spawning has been reported for one area in Oregon (Bond, in Behnke 1992). Eggs hatch after 6-7 weeks; hatchlings emerge from gravel in 1-2 weeks (March-June); first breeds at 2-4 years, lives 4-7 years (Moyle et al. 1989). In Oregon, sea-run trout typically migrate to salt water in the late spring or early summer at age 2 or age 3 (though some may never go to sea); after 2-5 months in the sea, they return to rivers (Behnke 1992). The timing of migrations, age at migrations, length of time spent at sea, and spawning time vary among stocks and geographical areas (Behnke 1992). Reportedly, about 40% survive first spawning (see Stearley 1992); however, Behnke (1992) reported lower values of 5-30%, varying with angling pressure; 12-17% survived between second and third and third and fourth spawnings in a stream little used by anglers (see Behnke 1992). Sea-run trout attain a maximum age of about 10 years (Behnke 1992). See Stearley (1992) for a discussion of the historical ecology and life history evolution of Pacific salmons and trouts (ONCORHYNCHUS).

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Conservation

Conservation Status

National NatureServe Conservation Status

Canada

Rounded National Status Rank: N3 - Vulnerable

United States

Rounded National Status Rank: N4 - Apparently Secure

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NatureServe Conservation Status

Rounded Global Status Rank: T4 - Apparently Secure

Reasons: Lack of adequate population estimates. Vulnerable to anthropogenic degradation of headwater streams and spawning areas. Difficult to distinguish from syntopic rainbow trout/steelhead.

Other Considerations: Difficult to distiguish juveniles from coastal rainbow trout and migrating adults from steelhead.

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Global Short Term Trend: Decline of 30 to >90%

Comments: Status difficult to determine due to difficulty in distinguishing juveniles from rainbow trout in the field; likely that populations have declined in recent years due to anthropogenic activities that degrade the required cold, high quality water (Moyle et al. 1989). In California, it is likely that populations have declined recently due to damage by logging. Sea-run cutthroat underwent a major decline in the 1970s and 1980s (Nehlsen et al. 1991). In Oregon, anadromous populations likely have undergone a significant decline in the late 1980s and 1990s; populations of other life-history types (resident, fluvial, adfluvial) are in better condition or are of unknown status (Hooton 1997).

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Threats

Degree of Threat: D : Unthreatened throughout its range, communities may be threatened in minor portions of the range or degree of variation falls within natural variation

Comments: Threats include habitat degradation (e.g., resulting from logging) and overfishing; for populations above Bonneville Dam, dam passage takes a toll; in many areas, native stocks have been eroded by introductions of hatchery stock (Nehlsen et al. 1991). In Oregon, the effects of clear-cutting (sedimentation, reduced cover, increased temperature) depressed populations for 6-8 years (see Behnke 1992). Can withstand catch-and-release fishing if not too frequent.

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Management

Management Requirements: Nonanadromous populations such as in Little Jones Creek (tributary of Smith River) in California may require special management to preserve their genetic integrity (Moyle et al. 1989). Key populations should be given special management designation; the Smith River population (apparently the largest in California) should be given special attention for population enhancement.

Efforts to enhance populations through artificial propagation should be designed to conserve the genetic integrity of wild stocks (Moyle et al. 1989).

See Nehlsen et al. (1991) for general protection and management recommendations for anadromous salmonids.

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Global Protection: Unknown whether any occurrences are appropriately protected and managed

Comments: In California, receives some protection in Redwood National Park, but fishing is still permitted.

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Relevance to Humans and Ecosystems

Benefits

Economic Uses

Comments: Sea-run trout provide popular local fisheries (Behnke 1992). After from coho and chinook salmon, this is the most popular game fish caught in marine watersof the Pacific Northwest.

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Wikipedia

Coastal cutthroat trout

Main article: Cutthroat trout

The coastal cutthroat trout (Oncorhynchus clarki clarki) also known as the sea run cutthroat, or harvest trout is one of 14 subspecies of cutthroat trout found in Western North America. The coastal cutthroat trout occurs in four distinct forms. A semi-anadromous or sea-run form is the most well known. Freshwater forms occur in both large and small rivers and streams and lake environments. The native range of the coastal cutthroat trout extends south from the southern coastline of the Kenai Peninsula in Alaska to the Eel River in Northern California. Coastal cutthroat trout are resident in tributary streams and rivers of the Pacific basin and are rarely found more than 100 miles (160 km) from the ocean.

Adults migrate from the ocean to spawn in fresh water. Juveniles migrate to the sea where they feed and become sexually mature before returning to fresh water to overwinter and spawn. Unlike steelhead and Pacific salmon, coastal cutthroat do not make lengthy migrations out to sea. Generally speaking, coastal cutthroat will remain in or near estuarine waters, usually within 5–10 mi (10–15 km) of their natal stream. Some cutthroat, however, have been shown to move as far as 70 mi (110 km) into the open ocean. There are also lacustrine and riverine populations that spend their entire lives in freshwater. One such population is the trout of Lake Crescent in Washington state that was formerly considered to be a separate subspecies called the Crescenti trout, Oncorhynchus clarki crescenti.

Taxonomy[edit]

Cutthroat trout were given the name Salmo clarki in honor of William Clark, who co-led the expedition of 1804–1806.[1] One of Lewis and Clark's missions was to describe the flora and fauna encountered during the expedition. The type specimen of S. clarki was described by naturalist John Richardson from a tributary of the lower Columbia River, identified as the "Katpootl",[1] which was perhaps the Lewis River as there was a Multnomah village of similar name at the confluence. This type specimen was most likely the coastal cutthroat subspecies.[2] In 1989, morphological and genetic studies by Gerald R. Smith, the Curator of Fishes at the Museum of Zoology, and Ralph F. Stearley, a doctoral candidate at Museum of Paleontology (University of Michigan) indicated trout of the Pacific basin were genetically closer to Pacific salmon (Oncorhynchus species) than to the Salmosbrown trout (S. trutta) or Atlantic salmon (S. salar) of the Atlantic basin.[3] Thus, in 1989, taxonomic authorities moved the rainbow, cutthroat and other Pacific basin trout into the genus Oncorhynchus.[4]

Description[edit]

Freshwater forms of the coastal cutthroat trout are generally dark green to greenish-blue on back, olive-green on upper flank, silvery on lower flank and belly. They display more numerous flank spots below lateral line, irregular spots on dorsal, adipose and caudal fins and the anal, pectoral and pelvic fin bases. The gill covers are pinkish. Sea-run forms while in salt water and shortly after returning to fresh water are silvery with a bluish back, yellowish lower flanks and fins, and display sparse spots. Cutthroats usually display distinctive red, pink, or orange linear marks along the undersides of their mandibles in the lower folds of the gill plates. These markings are responsible for the common name "cutthroat" given to the trout by outdoor writer Charles Hallock in an 1884 article in The American Angler.,[5] although the red slashes are not unique to the cutthroat trout and some coastal rainbow trout and redband trout also display throat slashes. The sea-run forms of coastal cutthroat average 2 to 5 lb (0.9 to 2.3 kg), while stream-resident forms attain much smaller sizes 0.4 to 3.2 oz (11 to 91 g).

Lifecycle[edit]

Coastal cutthroat trout usually inhabit and spawn in small to moderately large, clear, well-oxygenated, shallow rivers with gravel bottoms. They are native to the alluvial or freestone streams that are typical tributaries of the Pacific Basin. They typically spawn from December through June, with peak spawning in February. Eggs begin to hatch within six to seven weeks of spawning. Spawning begins when water temperatures reach 43 to 46°F (6 to 8°C). Depending on temperature, alevins emerge as fry between March and June, with peak emergence in mid-April.[2] Lake-resident coastal cutthroat trout are usually found in moderately deep, cool lakes with adequate shallows and vegetation for good food production. Lake populations generally require access to gravel-bottomed streams to be self-sustaining, but occasionally spawn on shallow gravel beds with good water circulation.[2]

Cutthroat trout naturally interbreed with the closely related rainbow trout, producing fertile hybrids commonly called "cutbows" although this is a much rarer occurrence with the coastal cutthroat trout because of reproductive isolation as the coastal cutthroat trout is the only cutthroat subspecies to coevolve through its entire range with the coastal rainbow trout (O. mykiss irideus). As this hybrid generally bears similar coloration and overall appearance to the cutthroat, retaining the characteristic orange-red slash, these hybrids often pose a taxonomic difficulty.[6]

Range and habitat[edit]

Photo of river mouth near ocean
Typical northwest saltwater estuary environment for cutthroat trout, Quillayute River, Washington
Photo of treelined mountain stream
Stream resident cutthroat habitat, North Santiam River, Oregon
Photo of beach in Puget Sound
Typical sea-run cutthroat habitat, Puget Sound beach

The native range of the coastal cutthroat trout extends south from the southern coastline of the Kenai Peninsula in Alaska to the Eel River in Northern California. Coastal cutthroat trout are resident in tributary streams and rivers of the Pacific basin and are rarely found more than 100 miles (160 km) from the ocean.[7] Semi-anadromous, stream resident, fluvial and lake resident forms exist.[7] The great majority of coastal cutthroat trout habitat coincides with the belt of Pacific coast coniferous rainforest that extends from Alaksa southward into Northern California.[8]

Coastal cutthroat trout use a large variety of habitat types, including lower and upper reaches of both large and small river systems, estuaries, sloughs, ponds, lakes, and near shore ocean waters. They spend more time in fresh water environments than other anadromous Pacific salmonids. In fresh water they prefer deeper pool habitat and cover, such as that formed by woody debris. The semi-anadromous forms of coastal cutthroat trout do not overwinter in saltwater and rarely make extended migrations across large bodies of water. Migrations in the marine environment are usually within 6 miles (9.7 km) of land. Semi-anadromous coastal cutthroat typically spend two to five years rearing in fresh water before making their initial migration into saltwater. Generally, semi-anadromous coastal cutthroat trout spend short periods offshore during summer months and return to estuaries and fresh water by fall or winter.[9]

Conservation status[edit]

The coastal cutthroat is a secure subspecies of the cutthroat trout. Although there has been a general population decline of the sea-run form throughout its native range since the 19th century, none of the populations in the United States or British Columbia are considered threatened or endangered. The U.S. Fish and Wildlife Service, in cooperation with the U.S. Environmental Protection Agency, National Marine Fisheries Service and state wildlife agencies has designated ten distinct population segments (DPS) from Alaska to California.[10][11] A comprehensive status review of the DPSs in 1999 determined that only one DPS, the Southwestern Washington/Columbia River DPS be proposed for threatened status under the Endangered Species Act. On July 5, 2002, after lengthy public comment and scientific evaluation, the U.S. Fish and Wildlife service withdrew its proposal to list the Southwestern Washington/Columbia River DPS as threatened.[11]

Stream resident, fluvial and lake forms are secure within their native range and supplemented by stocking of hatchery raised fish in Washington and Oregon.

Angling[edit]

Angling for cutthroat trout in Puget Sound

Sea-run coastal cutthroat trout fishery [12] [13]

Notes[edit]

  1. ^ a b c Richardson, John; William Swainson, William Kirby (1836), Fauna boreali-americana, or, The zoology of the northern parts of British America: containing descriptions of the objects of natural history collected on the late northern land expedition, under command of Captain Sir John Franklin, R.N., London: J. Murray, pp. 225–226 
  2. ^ a b c Behnke, Robert J.; Tomelleri, Joseph R. (illustrator) (2002). "Cutthroat trout Oncorhynchus clarki". Trout and Salmon of North America. The Free Press. pp. 137–234. ISBN 0-7432-2220-2. 
  3. ^ Gerald R. Smith, Ralph F. Stearley (1989). "The Classification and Scientific Names of Rainbow and Cutthroat Trouts". Fisheries (American Fisheries Society) 14 (1): 4–10. doi:10.1577/1548-8446(1989)014<0004:TCASNO>2.0.CO;2. 
  4. ^ Behnke, Robert J.; Tomelleri, Joseph R. (illustrator) (2002). "Genus Oncorhynchus". Trout and Salmon of North America. The Free Press. pp. 10–21. ISBN 0-7432-2220-2. 
  5. ^ Trotter, Patrick C. (2008). Cutthroat: Native Trout of the West (2nd ed.). Berkeley, CA: University of California Press. p. 13. ISBN 978-0-520-25458-9. 
  6. ^ Halverson, Anders (2010). "A Single New Mongrel Species". An Entirely Synthetic Fish: How Rainbow Trout Beguiled America and Overran the World. New Haven, CT: Yale University Press. pp. 145–164. ISBN 978-0-300-14087-3. 
  7. ^ a b Behnke, Robert J.; Tomelleri, Joseph R. (illustrator) (2002). "Coastal Cutthroat Trout Oncorhynchus clarki clarki". Trout and Salmon of North America. The Free Press. pp. 149–154. ISBN 0-7432-2220-2. 
  8. ^ Trotter, Patrick C. (2008). "Coastal Cutthroat Trout". Cutthroat: Native Trout of the West (2nd ed.). Berkeley, CA: University of California Press. pp. 59–101. ISBN 978-0-520-25458-9. 
  9. ^ "Species Fact Sheet Coastal Cutthroat Trout Oncorhynchus clarki" (PDF). U.S. Fish and Wildlife Service. Retrieved 2014-01-09. 
  10. ^ "Federal Register/Vol. 64, No. 64/Monday, April 5, 1999/Proposed Rules" (PDF). U.S. Fish and Wildlife Service. pp. 16397–16413. Retrieved 2014-01-09. 
  11. ^ a b Connolly, Patrick J., Williams, Thomas H. and Gresswell, Robert E., ed. (2008). "The 2005 Coastal Cutthroat Trout Symposium Status, Management, Biology, and Conservation" (PDF). Portland, Oregon: Oregon Chapter of the American Fisheries Society. 
  12. ^ Washington, Percy (December 1977). "The Sea-Run Cutthroat Trout Resource and Sport Fishery MFR Paper 1274" (PDF). Marine Fisheries Review 39 (12). 
  13. ^ Allen, Chester (May 26, 2009). "Fly Fishing for Puget Sound Sea-Run Cutthroat". WestFly. Retrieved 2014-04-08. 

Further reading[edit]

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Westslope cutthroat trout

Main article: Cutthroat trout

The westslope cutthroat trout (Oncorhynchus clarki lewisi), also known as the black-spotted trout, common cutthroat trout and red-throated trout is a subspecies of the cutthroat trout (Oncorhynchus clarki) and is a freshwater fish in the salmon family (family Salmonidae) of order Salmoniformes.[3] The cutthroat is the Montana state fish.[4] This subspecies is a species of concern in its Montana[5] and British Columbia[6] ranges and is considered threatened in its native range in Alberta.[7]

Taxonomy[edit]

The scientific name of the westslope cutthroat trout is Oncorhynchus clarki lewisi. The subspecies was first described in the journals of explorer William Clark from specimens obtained during the Lewis and Clark Expedition from the Missouri River near Great Falls, Montana. Cutthroat trout were given the name Salmo clarki in honor of William Clark, who co-led the expedition of 1804–1806.[8] One of Lewis and Clark's missions was to describe the flora and fauna encountered during the expedition. The type specimen of S. clarki was described by naturalist John Richardson in 1836 from a tributary of the lower Columbia River, identified as the "Katpootl",[8] which was perhaps the Lewis River as there was a Multnomah village of similar name at the confluence. This type specimen was most likely the coastal cutthroat subspecies.[9] In 1853, naturalist George Suckley while working for the Pacific Railroad Survey led by Isaac Stevens collected specimens of westslope cutthroat trout by fly fishing below the Great Falls on the Missouri river. In 1856, he described the trout as Salar lewisi to honor explorer Meriwether Lewis.[10] In David Starr Jordan and Barton Warren Evermann's A Check-list of the Fishes and Fishlike Vertebrates of North and Middle America (1896), the name Salmo mykiss lewisi was given to Yellowstone trout or cut-throat trout and included a reference to specimens collected from the Missouri river by George Suckley.[11] In 1898, Jordan and Evermann changed the name of cutthroat trout to Salmo clarki.[12] Salmo clarki lewisi persisted as the subspecies name for both the Yellowstone cutthroat and westslope cutthroat trout until 1971 when fisheries biologist Robert J. Behnke gave the name Salmo clarki bouvieri to the Yellowstone cutthroat with Salmo clarki lewisi reserved for the westslope cutthroat trout.[9]

In 1989, morphological and genetic studies indicated trout of the Pacific basin were genetically closer to Pacific salmon (Oncorhynchus species) than to the Salmosbrown trout (S. trutta) or Atlantic salmon (S. salar) of the Atlantic basin.[13] Thus, in 1989, taxonomic authorities moved the rainbow, cutthroat and other Pacific basin trout into the genus Oncorhynchus.[14]

Description[edit]

The fish has teeth under its tongue, on the roof of the mouth, and in the front of the mouth. Westslope cutthroat are common in both headwaters lake and stream environments. They feed mainly on insects and zooplankton. The average length of the fish is about 8-12 inches (30 cm) and rarely exceeds 18 inches (46 cm). The skin has small dark freckle-like spots clustered towards the tail, and is mostly orange-hued. They can be distinguished from rainbow trout by the red, pink, or orange marking beneath the jaw (whence the name "cutthroat").

Range[edit]

Westslope cutthroat trout are native in northern Idaho's and British Columbia's upper Columbia river system and northern tributaries of the Snake river, but not the Snake river's main stem to the south. East of the Continental Divide in Alberta and Montana, westslope cutthroat trout are native to the upper Missouri, Milk and North Saskatchewan rivers, but not the Yellowstone river to the south. In Montana, the historic range extended east to the mouth of the Judith river and south into the Madison, Gallatin and Jefferson river systems.[10] Isolated populations of westslope cutthroat trout exist in upper tributaries of the John Day river in the Strawberry Mountains of Oregon[15] and Columbia river tributaries along the eastern side of the Cascade range in Washington. Isolated populations exist in the Fraser river basin in British Columbia.[10] Existing populations of genetically pure westslope cutthroat trout exist in less than three percent of its historic range.

Life cycle[edit]

Westslope cutthroat trout reflect three life strategies—adfluvial, fluvial, or stream resident. Adfluvial fish live in the large lakes in the upper Columbia river drainage and spawn in lake tributaries. Fluvial fish live in medium to large rivers but migrate to tributaries for spawning. Most adults return to the river or lake after spawning. Stream resident fish complete their entire life in tributaries. All three forms occur in most basins.[16]

Conservation[edit]

Genetically pure westslope cutthroat trout have been extirpated throughout most of their historic range due to habitat loss and introduction of non-native species. Remaining populations survive in isolated populations, mostly in headwater streams above natural downstream barriers. The introduction of rainbow and brown trout into Missouri river tributaries eliminated the westslope cutthroat trout from most of its eastern range in Montana. Introductions of non-native kokanee salmon (Oncorhynchus nerka), lake trout (Salvelinus namaycush) and lake whitefish (Coregonus clupeaformis) into Flathead lake and the Flathead river system caused drastic declines in westslope cutthroat trout populations.[10] Existing populations are in imminent danger from land-use activities and hybridization with introduced rainbow trout (resulting in cutbows)[17] and Yellowstone cutthroat trout. Even the strongest populations in Glacier National Park and the Flathead Basin of Montana are in serious decline. Reasons for the critical condition of the subspecies include habitat destruction from logging, road building, grazing, mining, urban development, agriculture and dams, introduction of non-native hatchery strains, competition and hybridization from introduced non-native fish species.[citation needed]

Notes[edit]

  1. ^ Scott A. Deeds, Lynn R. Kaeding, Samuel C. Lohr, Douglas A. Young, Don Campton, Steve Duke, and Jim T. Mogen (September 1999). Status Review for Westslope Cutthroat Trout in the United States. U.S. Fish and Wildlife Service. p. 7. Retrieved 2014-02-20. 
  2. ^ "Synonyms of Oncorhynchus clarkii (Richardson, 1836)". Fishbase. Retrieved 2014-02-19. 
  3. ^ "Montana Field Guide-Westslope Cutthroat". Montana Department of Fish, Wildlife and Parks. Retrieved 2010-12-11. 
  4. ^ 1-1-507. State fish, Montana Code, accessed 23 April 2009.
  5. ^ Species of concern are native taxa that are at-risk due to declining population trends, threats to their habitats, restricted distribution, and/or other factors. Designation as a Montana species of concern or potential species of concern is based on the Montana Status Rank, and is not a statutory or regulatory classification. Rather, these designations provide information that helps resource managers make proactive decisions regarding species conservation and data collection priorities. See the latest species of concern reports for more detailed explanations and assessment criteria. "Montana Field Guide-Species of Concern". Retrieved 2010-12-07. 
  6. ^ "Aquatic Species at Risk - The Westslope Cutthroat Trout (British Columbia Population)". Fisheries and Oceans Canada. Retrieved 2014-02-19. 
  7. ^ "Aquatic Species at Risk - The Westslope Cutthroat Trout (Alberta Population)". Fisheries and Oceans Canada. Retrieved 2014-02-19. 
  8. ^ a b Richardson, John; William Swainson; William Kirby (1836). Fauna boreali-americana, or, The zoology of the northern parts of British America: containing descriptions of the objects of natural history collected on the late northern land expedition, under command of Captain Sir John Franklin, R.N.. London: J. Murray. pp. 225–226. 
  9. ^ a b Behnke, Robert J.; Tomelleri, Joseph R. (illustrator) (2002). "Cutthroat trout Oncorhynchus clarki". Trout and Salmon of North America. The Free Press. pp. 137–234. ISBN 0-7432-2220-2. 
  10. ^ a b c d Behnke, Robert J.; Tomelleri, Joseph R. (illustrator) (2002). "Westslope cutthroat trout Oncorhynchus clarki lewisi". Trout and Salmon of North America. The Free Press. pp. 155–162. ISBN 0-7432-2220-2. 
  11. ^ Jordan, David Starr and Evermann, Barton Warren (1896). A Check-list of the Fishes and Fishlike Vertebrates of North and Middle America. U.S. Commission of Fish and Fisheries. p. 291. 
  12. ^ Jordan, David Starr and Evermann, Barton Warren (1898). The Fishes of North and Middle America Part III. Smithsonian Institution. p. 2819. 
  13. ^ Smith, Gerald R.; Stearley, Ralph F.; Gerald R. Smith, Ralph F. Stearley (1989). "The Classification and Scientific Names of Rainbow and Cutthroat Trouts". Fisheries (American Fisheries Society) 14 (1): 4–10. doi:10.1577/1548-8446(1989)014<0004:TCASNO>2.0.CO;2.  Missing |last3= in Authors list (help)
  14. ^ Behnke, Robert J.; Tomelleri, Joseph R. (illustrator) (2002). "Genus Oncorhynchus". Trout and Salmon of North America. The Free Press. pp. 10–21. ISBN 0-7432-2220-2. 
  15. ^ Kevin Goodson, Bruce McIntosh, Mark Chilcote, and Charlie Corrarino, ed. (2005). "Westslope Cutthroat Trout" (PDF). "Oregon Native Fish Status Report – Volume II Assessment Methods & Population Results". Oregon Department of Fish and Wildlife. pp. 452–457. Retrieved 2014-02-20. 
  16. ^ Michael K. Young, ed. (September 1995). "Conservation Assessment for Inland Cutthroat Trout". U.S. Forest Service. 
  17. ^ Hitt, N.P., et al. (2003) Spread of hybridization between native westslope cutthroat trout, Oncorhynchus clarki lewisi, and nonnative rainbow trout, Oncorhynchus mykiss. Can. J. Fish. Aquat. Sci. 60, 1440-1451. doi:10.1139/F03-125

Further reading[edit]

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Whitehorse Basin cutthroat trout

The Whitehorse Basin cutthroat trout refers to a population segment of the cutthroat trout complex (Oncorhynchus clarki) from the streams of the Whitehorse Basin (or the Coyote Basin), southeastern Oregon. It is alternatively considered as a part of the Lahontan cutthroat trout subspecies (Oncorhynchus clarki henshawi),[1][2] or of the Humboldt cutthroat trout (O. c. humboldtensis) whose main range is in Nevada.[3]

Notes[edit]

  1. ^ U.S. Department of the Interior. Oregon Wilderness: Environmental Impact Statement 4. Bureau of Land Management. 
  2. ^ Species Fact Sheet: Lahontan cutthroat trout, U.S. Fish & Wildlife Service
  3. ^ Patrick C. Trotter and Robert J. Behnke (2008) The Case for Humboldtensis: A Subspecies Name for the Indigenous Cutthroat Trout (Oncorhynchus clarkii) of the Humboldt River, Upper Quinn River, and Coyote Basin Drainages, Nevada and Oregon Western North American Naturalist, 68(1):58-65.

Further reading[edit]

  • Trotter, Patrick C. (2008). Cutthroat: Native Trout of the West (2nd ed.). Berkeley, CA: University of California Press. ISBN 978-0-520-25458-9. 


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Names and Taxonomy

Taxonomy

Comments: According to Allendorf and Leary (1988), coastal, Lahontan, and westslope subspecies of O. CLARKI are electrophoretically divergent from other subspecies, closer to rainbow trout. However, mtDNA comparisons agree with other systematic and zoogeographical evidence that all subspecies of cutthroat trout are more closely related to each other than any of them is to rainbow trout (Gyllensten and Wilson 1987).

Nominal taxa CRESCENTIS and BATHOECETER are synonyms of O. C. CLARKI (Behnke 1992).

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