Alvord cutthroat trout
Encyclopedia
The Alvord cutthroat trout, Oncorhynchus clarki alvordensis, was a subspecies
Subspecies
Subspecies in biological classification, is either a taxonomic rank subordinate to species, ora taxonomic unit in that rank . A subspecies cannot be recognized in isolation: a species will either be recognized as having no subspecies at all or two or more, never just one...

 of cutthroat trout
Cutthroat trout
The cutthroat trout is a species of freshwater fish in the salmon family of order Salmoniformes. It is one of the many fish species colloquially known as trout...

. It was native to spring-fed creeks that ran down to Alvord Dry Lake
Alvord Lake (Oregon)
Alvord Lake is a seasonal shallow alkali lake in Harney County of the U.S. state of Oregon. Its elevation is . It is located about southeast of Alvord Desert in the Alvord Basin and serves as terminus for all its streams. Its water level varies from dry to several feet deep...

 in southeast Oregon
Oregon
Oregon is a state in the Pacific Northwest region of the United States. It is located on the Pacific coast, with Washington to the north, California to the south, Nevada on the southeast and Idaho to the east. The Columbia and Snake rivers delineate much of Oregon's northern and eastern...

, which was a large lake during the ice ages and an isolated drainage, part of the Great Basin
Great Basin
The Great Basin is the largest area of contiguous endorheic watersheds in North America and is noted for its arid conditions and Basin and Range topography that varies from the North American low point at Badwater Basin to the highest point of the contiguous United States, less than away at the...

 today. This is one of the two cutthroat trout taxa considered extinct
Extinction
In biology and ecology, extinction is the end of an organism or of a group of organisms , normally a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and recover may have been lost before this point...

 because all known populations are hybridized with Rainbow trout
Rainbow trout
The rainbow trout is a species of salmonid native to tributaries of the Pacific Ocean in Asia and North America. The steelhead is a sea run rainbow trout usually returning to freshwater to spawn after 2 to 3 years at sea. In other words, rainbow trout and steelhead trout are the same species....

 which were introduced into streams in the Alvord basin in the 1920s, resulting in cutbow
Cutbow
A Cutbow is a fertile hybrid between a rainbow trout and a cutthroat trout . While cutbow hybrids may occur naturally, most native populations of rainbows and cutthroats were separated by geography or habitat...

s.

The subspecies name was given in 2002 by Robert Behnke (Trout and Salmon of North America).

In the fall 2005 issue of Trout (the magazine of Trout Unlimited), in an article titled Ivory-Billed Trout, Dr. Behnke notes a historical reference that the now “extinct” Alvord Cutthroat Trout had been transplanted into another basin adjacent to the Alvord Basin, and that this transplant occurred prior to the 1928 introduction of rainbows into Trout Creek. Dr. Behnke reflects on which stream these trout may have been introduced into.

In the winter 2007 issue of Trout Magazine, in an article titled Toward Definitiveness, Dr. Behnke relates a summer 2006 electrofishing (sampling) project with the Oregon Department of Fish and Wildlife. He realized that the stream he’d referenced in 2005 was above the maximum Pleistocene lake level of any downstream flow-connected basins, and thus he doubts that redband trout ever made it to this elevated location.

In the late 50’s and through the 60’s ODFW had introduced Lahontan cutthroat trout and rainbow trout into this stream. During this trip he was pleased to find that all of the trout examined seemed to be of the Lahontan strain; with some trout exhibiting the appearance (phenotype) of the “extinct” Alvord cutthroat trout.

Dr. Behnke has urged the State of Oregon to create a population of trout phenotypically representative of the “extinct” alvordensis by transplanting specimens that most closely resemble alvordensis into presently fishless waters, where they can self-propagate and preserve the phenotype (if not genotype) of the Alvord cutthroat trout.
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