The Nonindigenous Occurrences section of the NAS species profiles has a new structure. The section is now dynamically updated from the NAS database to ensure that it contains the most current and accurate information. Occurrences are summarized in Table 1, alphabetically by state, with years of earliest and most recent observations, and the tally and names of drainages where the species was observed. The table contains hyperlinks to collections tables of specimens based on the states, years, and drainages selected. References to specimens that were not obtained through sighting reports and personal communications are found through the hyperlink in the Table 1 caption or through the individual specimens linked in the collections tables.

Catostomus ardens
Catostomus ardens
(Utah Sucker)
Native Transplant

Copyright Info
Catostomus ardens Jordan and Gilbert, 1881

Common name: Utah Sucker

Taxonomy: available through www.itis.govITIS logo

Identification: Page and Burr (1991); Sigler and Sigler (1996).

Size: 65 cm.

Native Range: Lake Bonneville basin in Utah, Idaho, Wyoming and Nevada and the Snake River above Shoshone Falls (Sigler and Sigler 1987, 1996).

Native range data for this species provided in part by NatureServe NS logo
Hydrologic Unit Codes (HUCs) Explained
Interactive maps: Point Distribution Maps

Nonindigenous Occurrences:

Table 1. States with nonindigenous occurrences, the earliest and latest observations in each state, and the tally and names of HUCs with observations†. Names and dates are hyperlinked to their relevant specimen records. The list of references for all nonindigenous occurrences of Catostomus ardens are found here.

StateFirst ObservedLast ObservedTotal HUCs with observations†HUCs with observations†
MT195119511Red Rock
UT198220105Duchesne; Fremont; Lower Green-Diamond; Strawberry; Upper Colorado-Dirty Devil
WY198219821Upper Green

Table last updated 6/15/2024

† Populations may not be currently present.

Ecology: Utah Suckers are found in a variety of habitat types and thermal regimes throughout their range, including shallow, seasonally warm streams and deep, cold reservoirs and lakes. They are benthic grazers, primarily consuming algae. Spawing occurs in spring over shallow gravel or sandy areas of small streams or lakeshores (Sigler and Sigler 1996).

Means of Introduction: Probably introduced to the Colorado River drainage via bait bucket (Sigler and Sigler 1996). Means of introduction in Montana unknown.

Status: Established in the Colorado basin, Utah and Wyoming. Single specimen collected from Montana in 1951 - failed.

Impact of Introduction: The primary cause of declines of flannelmouth suckers in Wyoming is the risk of genetic introgression with widely distributed non-native suckers (Bezzerides and Bestgen 2002; McDonald et al. 2008). Hybridization between native flannelmouth and bluehead sucker, and non-native white sucker Catostomus commersoni, longnose sucker C. catostomus, and Utah Sucker C. ardens is occurring. Some combinations are fertile and will lead to introgression (Wyoming Game and Fish Department 2010).

Remarks: Mock et al. (2006) found a large degree of genetic divergence among populations in the ancient Snake River and Bonneville Basin drainages, which does not coincide with patterns of morphological variation. In addition, they found no evidence of genetic divergence among morphologically divergent individuals in Utah Lake, including the federally endangered June sucker (Chasmistes liorus mictus).

Voucher specimens: Montana (UMMZ 173861). Montana specimen identified by R.R. Miller and R.M. Bailey.

References: (click for full references)

Bezzerides, N., and K. Bestgen. 2002. Status review of roundtail chub Gila robusta, flannelmouth sucker Catostomus latipinnis, and bluehead sucker Catostomus discobolus in the Colorado River basin. Final report submitted to the U.S. Department of Interior, Bureau of Reclamation Division of Planning. Larval Fish Lab Contribution 118, Colorado State University, Fort Collins, CO.

McDonald, D.B., T.L. Parchman, M.R. Bower, W.A. Hubert, and F.J. Rahel. 2008. An introduced and a native vertebrate hybridize to form a genetic bridge to a second native species. Proceedings of the National Academy of Science of the United States of America 105: 10842-10847.

Mock, K.E., R.P. Evans, M. Crawford, B.L. Cardall, S.U. Janecke, and M.P. Miller. 2006. Rangewide molecular structuring in the Utah sucker (Catostomus ardens). Molecular Ecology 15:2223-2238.

Page, L.M., and B.M. Burr. 1991. A field guide to freshwater fishes of North America north of Mexico. The Peterson Field Guide Series, volume 42. Houghton Mifflin Company, Boston, MA.

Sigler, W.F., and J.W. Sigler. 1987. Fishes of the Great Basin: A Natural History. University of Nevada Press, Reno, NV.

Sigler, W.F., and J.W. Sigler. 1996. Fishes of Utah. University of Utah Press, Salt Lake City, UT.

Tyus, H.M., B.D. Burdick, R.A. Valdez, C.M. Haynes, T.A. Lytle, and C.R. Berry. 1982. Fishes of the upper Colorado River basin: distribution, abundance, and status. 12-70 in W.H. Miller, H.M. Tyus, and C.A. Carlson, eds. Fishes of the upper Colorado River system: present and future, Western Division, American Fisheries Society.

Other Resources:
FishBase Summary

Author: Pam Fuller, and Matt Neilson

Revision Date: 2/6/2012

Peer Review Date: 2/6/2012

Citation Information:
Pam Fuller, and Matt Neilson, 2024, Catostomus ardens Jordan and Gilbert, 1881: U.S. Geological Survey, Nonindigenous Aquatic Species Database, Gainesville, FL, https://nas.er.usgs.gov/queries/FactSheet.aspx?SpeciesID=344, Revision Date: 2/6/2012, Peer Review Date: 2/6/2012, Access Date: 6/15/2024

This information is preliminary or provisional and is subject to revision. It is being provided to meet the need for timely best science. The information has not received final approval by the U.S. Geological Survey (USGS) and is provided on the condition that neither the USGS nor the U.S. Government shall be held liable for any damages resulting from the authorized or unauthorized use of the information.


The data represented on this site vary in accuracy, scale, completeness, extent of coverage and origin. It is the user's responsibility to use these data consistent with their intended purpose and within stated limitations. We highly recommend reviewing metadata files prior to interpreting these data.

Citation information: U.S. Geological Survey. [2024]. Nonindigenous Aquatic Species Database. Gainesville, Florida. Accessed [6/15/2024].

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For general information and questions about the database, contact Wesley Daniel. For problems and technical issues, contact Matthew Neilson.