The Colorado River cutthroat trout (''Oncorhynchus clarki pleuriticus'') is a subspecies of

cutthroat trout The cutthroat trout is a fish species of the family Salmonidae native to cold-water tributaries of the Pacific Ocean, Rocky Mountains, and Great Basin in North America. As a member of the genus '' Oncorhynchus'', it is one of the Pacific t ...

native only to the

Green Green is the color between cyan and yellow on the visible spectrum. It is evoked by light which has a dominant wavelength of roughly 495570 nm. In subtractive color systems, used in painting and color printing, it is created by a combin ...

and

Colorado River The Colorado River ( es, Río Colorado) is one of the principal rivers (along with the Rio Grande) in the Southwestern United States and northern Mexico. The river drains an expansive, arid watershed that encompasses parts of seven U.S. s ...

basins, which are west of the

Continental Divide A continental divide is a drainage divide on a continent such that the drainage basin on one side of the divide feeds into one ocean or sea, and the basin on the other side either feeds into a different ocean or sea, or else is endorheic, not c ...

Cutthroat trout The cutthroat trout is a fish species of the family Salmonidae native to cold-water tributaries of the Pacific Ocean, Rocky Mountains, and Great Basin in North America. As a member of the genus '' Oncorhynchus'', it is one of the Pacific t ...

found in other river basins belong to other subspecies.

Range

In the past, this subspecies was found throughout portions of the Colorado River drainage in

Wyoming Wyoming () is a state in the Mountain West subregion of the Western United States. It is bordered by Montana to the north and northwest, South Dakota and Nebraska to the east, Idaho to the west, Utah to the southwest, and Colorado to t ...

Colorado Colorado (, other variants) is a state in the Mountain West subregion of the Western United States. It encompasses most of the Southern Rocky Mountains, as well as the northeastern portion of the Colorado Plateau and the western edge of the ...

Utah Utah ( , ) is a state in the Mountain West subregion of the Western United States. Utah is a landlocked U.S. state bordered to its east by Colorado, to its northeast by Wyoming, to its north by Idaho, to its south by Arizona, and to its ...

Arizona Arizona ( ; nv, Hoozdo Hahoodzo ; ood, Alĭ ṣonak ) is a state in the Southwestern United States. It is the 6th largest and the 14th most populous of the 50 states. Its capital and largest city is Phoenix. Arizona is part of the Fou ...

, and

New Mexico ) , population_demonym = New Mexican ( es, Neomexicano, Neomejicano, Nuevo Mexicano) , seat = Santa Fe, New Mexico, Santa Fe , LargestCity = Albuquerque, New Mexico, Albuquerque , LargestMetro = Albuquerque metropolitan area, Tiguex , Offi ...

. However, today scientists believe this fish occupies 13% of its historic range (Range-Wide Status of Colorado River Cutthroat Trout (Oncorhynchus clarkii pleuriticus): 2005).

Colorado River cutthroats are thought to have occupied the basin of upper Muddy Creek, a tributary of the

Little Snake River The Little Snake River is a tributary of the Yampa River, approximately long, in southwestern Wyoming and northwestern Colorado in the United States. It rises near the continental divide, in Routt National Forest in northern Routt County, C ...

(which ultimately flows into the

) in southern Carbon County,

. Historical accounts in letters and diaries refer to them as "mountain trout" or "speckled trout." The fish may have begun to disappear from the upper Muddy Creek in the 1850s as a result of physical changes made to the environment by travelers, the introduction of the

brook trout The brook trout (''Salvelinus fontinalis'') is a species of freshwater fish in the char genus ''Salvelinus'' of the salmon family Salmonidae. It is native to Eastern North America in the United States and Canada, but has been introduced elsewhere ...

and other non-native species, and possibly the over-trapping of

beaver Beavers are large, semiaquatic rodents in the genus ''Castor'' native to the temperate Northern Hemisphere. There are two extant species: the North American beaver (''Castor canadensis'') and the Eurasian beaver (''C. fiber''). Beavers a ...

s, which affected dams and dependent habitats. A distinct lineage of Colorado River cutthroat trout known as the San Juan cutthroat was also found in the San Juan River and its tributaries, and was identified in 2012 by genetic testing of two specimens collected in 1874 near Pagosa Springs. While feared extinct, 8 isolated populations were discovered in and around the

San Juan National Forest The San Juan National Forest is a U.S. National Forest covering over 1,878,846 acres (2,935.7 sq mi, or 7,603.42 km²) in western Colorado. The forest occupies land in Archuleta, Conejos, Dolores, Hinsdale, La Plata, Mineral, Montezu ...

in mid-2018. Shortly after the rediscovery of the San Juan cutthroat, their remnant populations were threatened by the

416 Fire The 416 and Burro Fire Complex were two wildfires that burned in the southwestern portion of Colorado in the United States in 2018. The fires burned predominantly within San Juan National Forest, north of Durango and south of Rico. The 416 Fire ...

, which was closing in on their remaining habitat. In response, 58 San Juan cutthroats were removed from two remote creeks north of

Durango Durango (), officially named Estado Libre y Soberano de Durango ( en, Free and Sovereign State of Durango; Tepehuán: ''Korian''; Nahuatl: ''Tepēhuahcān''), is one of the 31 states which make up the 32 Federal Entities of Mexico, situated in ...

and are being held in hatcheries, with the ultimate goal of

captive breeding Captive breeding, also known as captive propagation, is the process of plants or animals in controlled environments, such as wildlife reserves, zoos, botanic gardens, and other conservation facilities. It is sometimes employed to help species tha ...

and reintroduction.

Conservation

Rangewide Conservation Agreements and Management Strategies are in place for this species.CONSERVATION AGREEMENT FOR COLORADO RIVER CUTTHROAT TROUT (Oncorhynchus clarkii pleuriticus) in the States of Colorado, Utah, and Wyoming
/ref> The Wyoming Game and Fish Department in cooperation with the Bureau of Land Management, Little Snake Conservation District, the U.S. Fish and Wildlife Service and Trout Unlimited have successfully reintroduced Colorado River cutthroat into the Little Snake River basin. Efforts have included improving stream habitat and removing non-native species.

Notes

;Citations ;Sources * *
Wyoming Fish & Game Commission

Range

Conservation

See also

Notes

Further reading