The Alvord cutthroat trout, Oncorhynchus clarkii alvordensis, was a subspecies of cutthroat trout.[2] It was known only from Trout Creek in Oregon and Virgin Creek in Nevada, although it may have lived in several of the larger Alvord Basin streams during recent times.[3] It was native to spring-fed creeks that ran down to Alvord Dry Lake in southeast Oregon, which was a large lake during the ice ages and an isolated drainage, part of the Great Basin today. This is one of the two cutthroat trout taxa considered extinct because all known populations are hybridized with rainbow trout which were introduced into streams in the Alvord basin in the 1920s, resulting in cutbows.[4]
The subspecies name was given in 2002 by Robert Behnke (Trout and Salmon of North America).
In the fall 2005 issue of Trout (Trout Unlimited's Journal of Coldwater Fisheries Conservation), in an article titled About Trout: 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 Behnke notes a historical reference that the now "extinct" Alvord Cutthroat Trout had been transplanted into another basin adjacent to the Alvord Basin, and that this transplant occurred prior to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.[5]
In the winter 2007 issue of Trout, in an article titled Toward Definitiveness, Dr. Behnke relates a summer 2006 electrofishing (sampling) project with the Oregon Department of Fish and Wildlife (ODFW). 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 1950s and through the 1960s the ODFW had introduced Lahontan cutthroat trout and rainbow trout into this stream, so Dr. Behnke expected to find a hybrid swarm during this sampling project. Yet, 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. In a 2007 publication of the Oregon Chapter of the American Fisheries Society, entitled Redband Trout Resilience and Challenge in a Changing Landscape, Dr. Behnke comments that he believes there is a strong possibility that trout caught in this stream circa World War II (confirmed by local historian Mr. Bruce Gilinski, who had direct experience on the stream just after World War II) were derived from the early transplant of the now extinct Alvord cutthroat. He thus surmises that what remains of the Alvord subspecies is incorporated into the trout now found in this small stream adjacent to the Alvord Basin.
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.
In April 2013, Shannon Hurn, ODFW Fisheries Biologist, Hines District (SE Oregon) has released a 2013 Management Proposal; which includes the plan to take spawning pairs of cutthroat trout that exhibit the phenotype of the extinct Alvord cutthroat trout, to relocate these pairs to the Klamath Hatchery in Oregon, and to propagate fry (offspring) from these pairs, to rear the trout at Klamath Hatchery, to look for uniformity among the sub-adult trout and to document the phenotype stages, and to ultimately transfer trout with the Alvord (alvordensis) phenotype to a suitable fishless host stream in SE Oregon (preferably in the Alvord Basin - the native realm of the extinct Alvord cutthroat trout).
Unfortunately, the plan for the project was not followed. Instead, based on visual inspection at the parr stage it was assumed by ODFW staff that the trout appeared to be cutthroat x rainbow trout hybrids (prior to the genetic results being completed) and the hatchery program was abandoned. This move proved premature and ill-timed, as once the results genetic study were available, it indicated that only ~3% of the genetics were from rainbow trout (Pritchard et al. 2015) Additionally, during the same period as that the hatchery program was initiated Southeastern Oregon was hit by several years of extreme drought. This resulted in an increase in fires along the stream and complete drying of some of the stream reaches. While the hatchery fish could have been returned to the stream to at least help buffer the drought conditions instead hatchery fish were released into Willow Valley Reservoir a body of water that is known for its warm water fisheries and is unlikely suitable for trout.[6]
Notes
↑ NatureServe (4 August 2023). "Oncorhynchus clarkii alvordensis". NatureServe Network Biodiversity Location Data accessed through NatureServe Explorer. Arlington, Virginia: NatureServe. Retrieved 20 August 2023.
↑ Hubbs, C.L.; Miller, R.R. (1948). "Correlation between fish distribution and hydrographic history in the desert basin of western United States in The Great Basin, with emphasis on glacial and postglacial times". Bulletin of the University of Utah. 38: 17–166.
↑ Trotter, Patrick C. (2008). "Extinct Subspecies". Cutthroat: Native Trout of the West (2nded.). Berkeley, CA: University of California Press. pp.459–465. ISBN978-0-520-25458-9.
Trout is a generic common name for numerous species of carnivorous freshwater ray-finned fishes belonging to the genera Oncorhynchus, Salmo and Salvelinus, all of which are members of the subfamily Salmoninae in the family Salmonidae. The word trout is also used for some similar-shaped but non-salmonid fish, such as the spotted seatrout/speckled trout.
The rainbow trout is a species of trout native to cold-water tributaries of the Pacific Ocean in North America and Asia. The steelhead is an anadromous (sea-run) form of the coastal rainbow trout(O. m. irideus) or Columbia River redband trout (O. m. gairdneri) that usually returns to freshwater to spawn after living two to three years in the ocean. Freshwater forms that have been introduced into the Great Lakes and migrate into tributaries to spawn are also called steelhead.
The cutthroat trout is a group of four fish species of the family Salmonidae native to cold-water tributaries of the Pacific Ocean, Rocky Mountains, and Great Basin in North America. These four species are the Coastal, Westslope, Lahontan, and the Rocky Mountain. As a member of the genus Oncorhynchus, it is in the Pacific trout group, which includes the widely distributed rainbow trout. Cutthroat trout are popular gamefish, especially among anglers who enjoy fly fishing. The common name "cutthroat" refers to the distinctive red coloration on the underside of the lower jaw. The specific name clarkii was given to honor explorer William Clark, coleader of the Lewis and Clark Expedition.
Oncorhynchus is a genus of ray-finned fish in the subfamily Salmoninae of the family Salmonidae, native to coldwater tributaries of the North Pacific basin. The genus contains twelve extant species, namely six species of Pacific salmon and six species of Pacific trout, all of which are migratory mid-level predatory fish that display natal homing and semelparity.
Lahontan cutthroat trout is the largest subspecies of cutthroat trout and the state fish of Nevada. It is one of three subspecies of cutthroat trout that are listed as federally threatened.
Redband trout are a group of three recognized subspecies of rainbow trout. They occur in three distinct regions in Pacific basin tributaries and endorheic basins in the western United States. The three subspecies are the Columbia River redband trout, the McCloud River redband trout and the Great Basin redband trout.
The Colorado River cutthroat trout is a subspecies of cutthroat trout native only to the Green and Colorado River basins, which are west of the Continental Divide.
The greenback cutthroat trout is the easternmost subspecies of cutthroat trout. The greenback cutthroat, once widespread in the Arkansas and South Platte River drainages of Eastern Colorado and Southeast Wyoming, today occupies less than 1% of its historical range. It is currently listed as threatened under the Endangered Species Act. It was adopted as the state fish of Colorado on March 15, 1994, replacing the unofficial rainbow trout.
The Snake River fine-spotted cutthroat trout is a form of the cutthroat trout that is considered either as a separate subspecies O. c. behnkei, or as a variety of the Yellowstone cutthroat trout. The fish takes its common name from its original habitat, the Snake River of southern Idaho and western Wyoming, and from its unusual pattern of hundreds of small spots that cover most of its body, differing from the larger-spotted Yellowstone cutthroat pattern. Genetically, it cannot be distinguished from the Yellowstone cutthroat trout, and before the construction of dams, no physical barriers were between the ranges of the two subspecies in the Snake River drainage.
The westslope cutthroat trout is a freshwater salmonid in the cutthroat trout complex. The nominate subspecies, also known as the westslope cutthroat trout, is Oncorhynchus lewisi lewisi. The westslope cutthroat trout is the Montana state fish. The westslope cutthroat trout is a species of concern in Montana and British Columbia ranges and is considered threatened in its native range in Alberta.
The coastal cutthroat trout, also known as the sea-run cutthroat trout, blue-back trout or harvest trout, is one of the four species 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.
The Crescenti cutthroat trout or the Lake Crescent cutthroat trout is a North American freshwater fish, a local form of the coastal cutthroat trout isolated in Lake Crescent in Washington. While previously attributed to a distinct subspecies Oncorhynchus clarkii crescenti, it is not currently recognized at the subspecies rank. However the cutthroat trout of Lake Crescent do remain distinct. They have the highest known gill raker and vertebrae counts of any coastal cutthroat population. The cutthroat are believed to have been isolated in Lake Crescent after a landslide blocked the eastern outflow of the lake.
Paiute cutthroat trout is one of fourteen subspecies of cutthroat trout. Paiute Cutthroat are native only to Silver King Creek, a headwater tributary of the Carson River in the Sierra Nevada, in California. This subspecies is named after the indigenous Northern Paiute peoples.
The cutbow is an interspecific fertile hybrid between rainbow trout and cutthroat trout. While natural separation of spawning habitat limited hybridization in most native populations of rainbow and cutthroat trout, introduction of non-native hatchery-raised rainbow trout into native cutthroat trout range increased hybridization across the landscape. Due to these introductions, many populations of cutthroat trout are at risk of genetic pollution. As a result, significant management intervention at state and federal levels has occurred to preserve native populations of cutthroat trout.
The Humboldt cutthroat trout is a subspecies of cutthroat trout, a North American fish in the family Salmonidae. It is one of the several subspecies of cutthroat trout. It was formally scientifically named in 2008 by Trotter and Behnke, who stated its distribution is in the basins of the upper Humboldt River of northern Nevada, the Upper Quinn River, as well as the Whitehorse (Coyote) basin (Oregon). The Nevada and Oregon Fish and Wildlife authorities still consider these populations belonging to the subspecies O. c. henshawi.
The McCloud River redband trout is one of three redband trout subspecies of the rainbow trout in the family Salmonidae. The trout is native in small tributaries of the McCloud River and Pit River which are tributaries of California's Sacramento River. Its historic range has declined significantly since it was first described in 1894. Remaining populations of genetically pure McCloud River redband trout are threatened by predation, habitat loss, competition with introduced trout species and by hybridization with hatchery rainbow trout introduced to support sport fishing.
The Willow-Whitehorse Basin cutthroat trout refers to a population segment of the cutthroat trout complex from the streams of the Whitehorse Basin, southeastern Oregon. It is alternatively considered as a part of the Lahontan cutthroat trout subspecies, or of the Humboldt cutthroat trout whose main range is in Nevada. These fish have adapted to live under extreme conditions, and can withstand water temperatures as high as 85 °F for short periods of time.
The Little Kern golden trout is a brightly colored subspecies of rainbow trout native to the main stem and tributaries of the Little Kern River in Tulare County, California. Together with the California golden trout and the Kern River rainbow trout, the Little Kern golden trout forms what is sometimes referred to as the "golden trout complex" of the Kern River basin.
The Rocky Mountain cutthroat trout(Oncorhynchus virginalis), formerly lumped in with the cutthroat trout as one species with multiple subspecies, is a fish species of the family Salmonidae native to cold-water tributaries of the northern and southern Rocky Mountains, as well as into portions of the Great Basin in North America. As a member of the genus Oncorhynchus, it is a part of the Pacific trout group, which includes the widely distributed rainbow trout. Cutthroat trout are popular gamefish, especially among anglers who enjoy fly fishing. The common name "cutthroat" refers to the distinctive red coloration on the underside of the lower jaw.
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