The Owens pupfish (''Cyprinodon radiosus'') is a rare species of

fish Fish are aquatic, craniate, gill-bearing animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish as well as various extinct related groups. Approximately 95% ...

in the family Cyprinodontidae, the pupfish. It is

endemic Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found els ...

California California is a state in the Western United States, located along the Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the most populous U.S. state and the 3rd largest by area. It is also the ...

in the United States, where it is limited to the

Owens Valley Owens Valley (Numic: ''Payahǖǖnadǖ'', meaning "place of flowing water") is an arid valley of the Owens River in eastern California in the United States. It is located to the east of the Sierra Nevada, west of the White Mountains and Inyo Mo ...

. It is a federally listed endangered species of the United States. This pupfish is up to long, the largest males sometimes longer. The male is blue-gray, turning bright blue during

spawning Spawn is the eggs and sperm released or deposited into water by aquatic animals. As a verb, ''to spawn'' refers to the process of releasing the eggs and sperm, and the act of both sexes is called spawning. Most aquatic animals, except for aqua ...

. The female is greenish brown with a silvery or whitish belly.Pister, E. P. (2001)
Threatened fishes of the world: ''Cyprinodon radiosus'' Miller, 1948 (Cyprinodontidae).
''Environmental Biology of Fishes'' 61: 370. Retrieved September 29, 2011. The pupfish tolerates a wide range of water conditions. Its native habitat includes desert

marsh A marsh is a wetland that is dominated by herbaceous rather than woody plant species.Keddy, P.A. 2010. Wetland Ecology: Principles and Conservation (2nd edition). Cambridge University Press, Cambridge, UK. 497 p Marshes can often be found a ...

es with water temperatures up to 33 °C in the summer and layers of ice during the winter. The water in some areas has four times the salt content of the ocean, as well as low oxygen.Owens Pupfish ''Cyprinodon radiosus''.
Bureau of Land Management Species Profile. Retrieved September 29, 2011. This fish was once common in the Owens Valley of California, occurring in most water bodies between Fish Slough and Lone Pine, which are 70 miles apart. It occurred in the

Owens River The Owens River is a river in eastern California in the United States, approximately long.U.S. Geological Survey. National Hydrography Dataset high-resolution flowline dataThe National Map accessed March 17, 2011, It drains into and through the ...

and associated

slough Slough () is a town and unparished area in the unitary authority of the same name in Berkshire, England, bordering west London. It lies in the Thames Valley, west of central London and north-east of Reading, at the intersection of the M4, ...

s and marshes. At that time the

Paiute people Paiute (; also Piute) refers to three non-contiguous groups of indigenous peoples of the Great Basin. Although their languages are related within the Numic group of Uto-Aztecan languages, these three groups do not form a single set. The term "Paiu ...

scooped them out of the water and dried them for the winter.USFWS
''Cyprinodon radiosus'' Five-year Review.
(February 2009). Retrieved September 29, 2011. The diversion of water from the Owens River to the

Los Angeles Metropolitan Area Greater Los Angeles is the second-largest urban area, metropolitan region in the United States with a population of 18.5 million in 2021, encompassing five counties in Southern California extending from Ventura County in the west to San Ber ...

during the California Water Wars eliminated most of the water bodies that were the pupfish's habitat. Predation by

introduced species An introduced species, alien species, exotic species, adventive species, immigrant species, foreign species, non-indigenous species, or non-native species is a species living outside its native distributional range, but which has arrived the ...

of fish may have decimated remaining populations. By 1942 this pupfish was believed to be extinct. It was rediscovered in 1964, when one population of about 200 individuals was found. When they were transferred to a safer location, the entire global population of this pupfish was contained in two buckets.Pister, E. P
Species in a bucket.
''Natural History Magazine'' (January 1993). pg 14. Retrieved September 29, 2011.Terrill, C. "Islands". In: Albert, S. W
What Wildness is This: Women Write About the Southwest.
University of Texas Press. (2007). pg 129. Retrieved September 29, 2011. The

California Department of Fish and Game The California Department of Fish and Wildlife (CDFW), formerly known as the California Department of Fish and Game (CDFG), is a state agency under the California Natural Resources Agency. The Department of Fish and Wildlife manages and protec ...

established six populations in carefully managed refuge using these fish. Four of these populations remain today. Threats to the four populations include the encroachment of

cattail ''Typha'' is a genus of about 30 species of monocotyledonous flowering plants in the family Typhaceae. These plants have a variety of common names, in British English as bulrush or reedmace, in American English as reed, cattail, or punks, in ...

s into the waterways. The plant clogs the habitat and collects detritus, which eliminates the pupfish's breeding substrates. The CDFG tends the four populations, clearing out the cattails. Introduced species of aquatic organisms also pose a threat. They include predatory fish such as

largemouth bass The largemouth bass (''Micropterus salmoides'') is a carnivorous freshwater gamefish in the Centrarchidae ( sunfish) family, a species of black bass native to the eastern and central United States, southeastern Canada and northern Mexico, b ...

(''Micropterus salmoides''), smallmouth bass (''Micropterus dolomieu''),

brown trout The brown trout (''Salmo trutta'') is a European species of salmonid fish that has been widely introduced into suitable environments globally. It includes purely freshwater populations, referred to as the riverine ecotype, ''Salmo trutta'' morp ...

(''Salmo trutta''), and bluegill (''Lepomis macrochirus''), as well as

crayfish Crayfish are freshwater crustaceans belonging to the clade Astacidea, which also contains lobsters. In some locations, they are also known as crawfish, craydids, crawdaddies, crawdads, freshwater lobsters, mountain lobsters, rock lobsters, ...

(''Pacifastacus leniusculus'') and bullfrogs (''Rana catesbeiana''). The severe reduction of the species into a single small population may have created a

genetic bottleneck A population bottleneck or genetic bottleneck is a sharp reduction in the size of a population due to environmental events such as famines, earthquakes, floods, fires, disease, and droughts; or human activities such as specicide, widespread violen ...

;

genetic analysis Genetic analysis is the overall process of studying and researching in fields of science that involve genetics and molecular biology. There are a number of applications that are developed from this research, and these are also considered parts of ...

is underway. Other local ''Cyprinodon'' include Death Valley pupfish (''Cyprinodon salinus salinus''), Shoshone pupfish (''Cyprinodon nevadensis shoshone''), the extinct Tecopa pupfish (''Cyprinodon nevadensis calidae''),

Devils Hole pupfish The Devils Hole pupfish (''Cyprinodon diabolis'') is a critically endangered species of the family Cyprinodontidae (pupfishes) found only in Devils Hole, a water-filled cavern in the US state of Nevada. It was first described as a species in 19 ...

(''Cyprinodon diabolis''), and the desert pupfish (''Cyprinodon macularius'').

References

External links

* Terrill, C
Pister's Pupfish
myurbanwild.com {{Taxonbar, from=Q305777 Cyprinodon Endemic fauna of California Fauna of the Mojave Desert Fish of the Western United States Freshwater fish of the United States Owens Valley Natural history of Inyo County, California Fish described in 1948 Taxa named by Robert Rush Miller Endangered fauna of California Taxonomy articles created by Polbot ESA endangered species