{{Short description|Species of fish}} {{Speciesbox | status = EN | status_system = IUCN3.1 | status_ref = <ref name="iucn status 16 November 2021">{{cite iucn |author=NatureServe |author-link=NatureServe |year=2014 |title=''Catostomus warnerensis'' |article-number=e.T4051A2932919 |doi=10.2305/IUCN.UK.2014-3.RLTS.T4051A2932919.en |access-date=16 November 2021}}</ref> | status2 = G1 | status2_system = TNC | status2_ref = <ref name=NS>{{cite NatureServe |id=2.100954 |title=''Catostomus warnerensis'' |access-date=16 March 2025}}</ref> | image = Catostomus warnerensis.jpg | image2 = Catostomus warnerensis illustration.jpg | taxon = Catostomus warnerensis | authority = Snyder, 1908 }}
The '''Warner sucker''' ('''''Catostomus warnerensis''''') is a rare species of freshwater ray-finned fish in the family Catostomidae. Native to Oregon in the United States and found only in the Warner Basin, its distribution extends just into Nevada<ref name=NS/> and California.<ref name=five>{{cite web|publisher=USFWS|url=http://ecos.fws.gov/docs/five_year_review/doc3356.pdf |title=''Catostomus warnerensis'' Five-year Review|date= August 2010}}</ref> It is a federally listed threatened species. Its other common name is '''redhorse'''.<ref name=ebf>{{cite journal|author=Williams, J. E. |year=1995 |doi=10.1007/BF00008249 |title=Threatened fishes of the world: ''Catostomus warnerensis'' Snyder, 1908 (Catostomidae)|journal=Environmental Biology of Fishes|volume= 44|issue=4|page= 346 |bibcode=1995EnvBF..44..346W }}</ref> The International Union for Conservation of Nature has rated this fish as an endangered species because of its small extent of occurrence, the small number of locations in which it is found, and the extreme fluctuations in area of occupancy resulting from drought and water abstraction. Conservation efforts have been put in place.
==Description== This sucker is up to about {{convert|15+3/4|in|cm}} in length. It has a dark back and sides and a white belly. The male and some females take on a bright red wash along the sides during the spawning season. The fish spawns in the creeks when they are full in the spring, as well as in canals and on lakeshores. The fish can reach the age of twenty.<ref name=ebf/> It becomes sexually mature at three or four.<ref name=NS/>
==Distribution== This fish is native to shallow lakes and associated marshes and intermittent lakes and creeks in the Warner Valley of Lake County, Oregon. It has been seen in Twelvemile Creek just over the border in Nevada<ref name=ebf/> and West Barrel Creek within California state lines.<ref name=five/> It was historically quite abundant in the valley.<ref name=ebf/> There is only one metapopulation of the fish, made up of several subpopulations.<ref name=NS/> There are two morphs, one that lives in the lakes and one that stays in stream habitat past spawning time.<ref name=NS/> The lake-dwelling morph is generally larger in size. The stream morph may be the only one that is now experiencing recruitment.<ref name=five/>
==Status== Threats to the species include the many dams which have been installed in the local creeks to divert water for agriculture. These impoundments prevent fish migration and reduce the stream flows. The spawning grounds may be polluted and loaded with excessive silt.<ref name=NS/> The introduced crappie (''Pomoxis'' spp.) may be a predator on the juvenile sucker. Drought is also a current threat.<ref name=ebf/> The drought conditions are then made worse with increased irrigation demands on the dwindling water supply.<ref name=NS/> The International Union for Conservation of Nature has rated this fish as an endangered species because of its small extent of occurrence, the small number of locations in which it is found, and the extreme fluctuations in area of occupancy resulting from changes in the amount of available habitat.<ref name="iucn status 16 November 2021" />
Conservation efforts include the restoration of riparian vegetation and the construction of a fishway at a dam on a major creek. Individuals have been transplanted to Summer Lake Wildlife Management Area when they were threatened by drought conditions; these fish died but not before successfully reproducing in their new habitat.<ref name=five/> Conservation activities in the area have been shown to benefit the Great Basin redband trout (''Oncorhynchus mykiss newberrii'') as well as the sucker.<ref name=ebf/>
==References== {{Reflist}}
==External links== * {{FishBase|Catostomus|warnerensis}}
{{Taxonbar|from=Q307096}}
Warner sucker Category:Endemic fish of the United States Category:Fish of the Western United States Category:Freshwater fish of the United States Category:Fauna of the Great Basin Category:Fauna of California Category:Natural history of Oregon Category:Natural history of Nevada Category:Endangered fauna of California Category:Endangered fauna of the United States Category:Taxonomy articles created by Polbot Category:ESA threatened species Category:Fish described in 1908 Category:Taxa named by John Otterbein Snyder