View source for Cui-ui

{{Short description|Species of fish}}
{{Speciesbox
 | image               = FMIB 38962 Chasmistes cujus 'Cui-ui'.jpeg
 | status              = EN
 | status_system       = IUCN3.1
 | status_ref          = <ref>{{Cite iucn | author = NatureServe | title = ''Chasmistes cujus'' | volume = 2014 | page = e.T4586A3003395 | date = 2014 | doi = 10.2305/IUCN.UK.2014-3.RLTS.T4586A3003395.en }}</ref>
| status2 = CITES_A1 
 | status2_system = CITES 
 | status2_ref = <ref>{{Cite web|title=Appendices {{!}} CITES|url=https://cites.org/eng/app/appendices.php|access-date=2022-01-14|website=cites.org}}</ref>
 | taxon            = Chasmistes cujus
 | authority  = [[Edward Drinker Cope|Cope]], 1883
}}

The '''cui-ui''' ('''''Chasmistes cujus''''') is a large [[Catostomidae|sucker]] [[fish]] [[Endemism|endemic]] to [[Pyramid Lake (Nevada)|Pyramid Lake]] and, prior to its [[desiccation]] in the 20th century, [[Winnemucca Lake]] in northwestern [[Nevada]].<ref>{{cite web| last =Scoppettone| first =G. Gary| author2 =Rissler, Peter H.| url =http://biology.usgs.gov/s+t/noframe/r250.htm| title =Endangered Cui-ui of Pyramid Lake, Nevada| work =Our Living Resources, A Report to the Nation on the Distribution, Abundance, and Health of U.S. Plants, Animals, and Ecosystems |publisher=U.S. Department of the Interior National Biological Service | access-date =2006-06-03 |archive-url=https://web.archive.org/web/20060925013929/http://biology.usgs.gov/s%2Bt/noframe/r250.htm| archive-date =2006-09-25| url-status =dead}}</ref>  It feeds primarily on [[zooplankton]] and possibly on [[nanoplankton]] (such as algae and [[diatoms]]). The maximum size of male cui-ui is approximately {{convert|53|cm|in|abbr=on}} and {{convert|1.6|kg|lb|abbr=on}}, while females reach approximately {{convert|64|cm|in|abbr=on}} and {{convert|2.7|kg|lb|abbr=on}}. A cui-ui typically lives for 40 years but does not reach sexual maturity until at least age eight. The cui-ui is an [[endangered species]], and one of the few surviving members of its genus.<ref>Truckee-Carson-Pyramid Lake Water Rights Settlement Act: Hearing Before the Subcommittee on Water before the United States Congress, Senate Committee on Energy and Natural Resources. Subcommittee on Water and Power (1990)</ref>

The cui-ui population is generally improving in numbers, having attained an estimated population exceeding one million in 1993, thanks to the efforts of the [[United States Environmental Protection Agency|U.S. Environmental Protection Agency]] in analysis of the [[Truckee River]] [[spawn (biology)|spawning]] grounds and of the Nevada Department of Environmental Protection and EPA in following up on protection measures. The reason the cui-ui remains endangered (though upgraded from critically endangered in 2014) is the recent history of [[recruitment (biology)|recruitment]] variation, illustrating that in many years of the 1970s and 1980s there was virtually no recruitment whatsoever due to unsuccessful spawning in an unfavorable water quality and water flow environment of the Truckee River. The species' outlook is uncertain since a recovery plan based on an enhanced understanding of Pyramid Lake and Truckee River water quality has been published and U.S. Congress adopted a protection plan.<ref>United States Congress, [https://www.congress.gov/101/statute/STATUTE-104/STATUTE-104-Pg3289.pdf Public Law 101-618], Section 207.  16 November 1990.  Accessed 17 April 2023 via congress.gov.</ref>

==Pyramid Lake water quality==
[[Image:Pyramid lake pah rah.jpg|thumb|240px|Pyramid Lake is the only location cui-ui are found.]]
Pyramid Lake, the second largest natural lake in the western U.S. prior to construction of the [[Derby Dam]], has been the focus of several water quality investigations, the most detailed starting in the mid-1980s. Under direction of the U.S. Environmental Protection Agency, a comprehensive dynamic [[hydrology transport model]] was developed<ref>C.M.Hogan, Marc Papineau ''et al.'', ''Development of a dynamic water quality simulation model for the Truckee River'', Earth Metrics Inc., Environmental Protection Agency Technology Series Washington D.C. (1987)</ref> by Earth Metrics Inc.; the model's name was subsequently changed to [[DSSAM Model|DSSAM]], and it was applied to analyze impacts of a variety of land use and wastewater management decisions throughout the {{convert|3120|sqmi|km2|adj=on}} Truckee River Basin. Analytes addressed included nitrogen, reactive phosphate, dissolved oxygen, and ten other parameters. Based upon use of the model, some decisions have been influenced to enhance Pyramid Lake water quality and aid the viability of Pyramid Lake [[biota (ecology)|biota]], including the cui-ui. The dynamic river model was particularly useful for analyzing Truckee River temperature variations, since the cui-ui often swim upstream to spawn, and their [[spawn (biology)|fry]] are vulnerable to elevations in river temperature.

==Spawning behavior==
The cui-ui is [[potamodromous]], and will attempt to ascend the Truckee River to spawn in mid-April. If inflow is insufficient to permit this, the cui-ui may attempt to spawn in Pyramid Lake, but generally with little success due to the salinity of that lake.<ref>Charles F Wilkinson, ''Crossing the Next Meridian'', Island Press, (1992) {{ISBN|1-55963-149-X}}</ref> Water releases from the Boca reservoir and [[Stampede Dam|Stampede]] reservoirs were ({{as of|2004|lc=y}}) timed to assist the spawning run, although in drought years this water is reserved for the [[Reno, Nevada|Reno]] metropolitan area. These releases are critical to successful spawning since low warm flows at the Truckee River delta are inhospitable to upstream migration of adults.

The [[Pyramid Lake Paiute Tribe of the Pyramid Lake Reservation]] maintain three hatcheries to ensure the long term viability of the cui-ui.<ref>{{cite news |last1=Solis |first1=Jennifer |title=Tribe works to keep home of endangered fish free of invasive species |url=https://www.nevadacurrent.com/2022/01/03/tribe-works-to-keep-home-of-endangered-fish-free-of-invasive-species/ |access-date=6 June 2023 |work=Nevada Current |date=3 January 2022}}</ref> These measures have greatly increased cui-ui populations, although it is still listed as an endangered species.

== Cultural history ==
[[Image:Marble bluff cui ui3.jpg|thumb|Cui-ui]]
The Pyramid Lake Paiute Tribe are the Cui-ui Ticutta, also spelled ''Kuyuidikado'', which translated to "cui-ui eaters."<ref>{{cite web |title=Cui-ui |url=https://truckeeriverguide.org/species/cui-ui/ |website=Truckee River Guide |access-date=6 June 2023}}</ref> Together with the [[Lahontan cutthroat trout]] (''Oncorhynchus clarkii henshawi'') the cui-ui was an important food supply for the Cui-ui Tikutta and neighboring Paiute bands who traveled to Pyramid Lake to share in the harvest during the spring spawning runs.

Subsequent to European American settlement of western Nevada in the 1860s many Cui-ui Ticutta made a living by selling fish, although the European Americans generally preferred trout to cui-ui. Cui-ui were also still important for subsistence, despite [[Bureau of Indian Affairs]] attempts to encourage farming and discourage fishing.

After the 1905 construction of [[Derby Dam]] which diverted much of the Truckee River's flow, the Pyramid Lake fishery declined. By 1930, it no longer supplied even subsistence food. Although conditions have improved recently, the cui-ui are managed for cultural and ecological purposes, not as a human food source.

==See also==
* [[Surface runoff]]
* [[Thermal pollution]]

== References==
{{Reflist}}

==External links==
{{Commons category|Chasmistes cujus}}
* [https://web.archive.org/web/20060502110555/http://pyramidlakefisheries.org/Cui-ui.htm Koch Cui-ui Hatchery]
* [https://web.archive.org/web/20070614085013/http://www.usbr.gov/mp/lbao/endangered_species.html U.S. Department of Interior cui-ui article]

{{Taxonbar|from=Q1149559}}
{{Authority control}}

[[Category:Chasmistes]]
[[Category:Endemic fauna of Nevada]]
[[Category:Endemic fish of the United States]]
[[Category:Freshwater fish of the United States]]
[[Category:Fish of the Western United States]]
[[Category:Fauna of the Great Basin]]
[[Category:Washoe County, Nevada]]
[[Category:Endangered fish]]
[[Category:Endangered fauna of the United States]]
[[Category:ESA endangered species]]
[[Category:Fish described in 1883]]
[[Category:Taxa named by Edward Drinker Cope]]