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.

Cottus bairdii
Cottus bairdii
(Mottled Sculpin)
Native Transplant

Copyright Info
Cottus bairdii Girard, 1850

Common name: Mottled Sculpin

Taxonomy: available through www.itis.govITIS logo

Identification: Wydoski and Whitney (1979); Becker (1983); Page and Burr (1991); Jenkins and Burkhead (1994).  Original spelling end with ii (Nelson et al. 2004).

Size: to 15 cm TL (Page and Burr 1991).

Native Range: This species has a broad distribution, with disjunct eastern and western populations. In eastern North America it occurs in the Arctic, Atlantic, and Mississippi River basins from Labrador and northern Quebec west to western Manitoba, and south to the Roanoke River drainage, Virginia, and the Tennessee River drainage, northern Georgia and Alabama, with isolated populations in the extreme upper Santee (North Carolina), Savannah (South Carolina and Georgia), Chattahoochee (Georgia), Coosa (Georgia), and Osage (Missouri) River systems. In western North America populations exist in the upper Missouri River basin, in Alberta, Montana, and Wyoming; in the Columbia River drainage from British Columbia south to Oregon and east to Wyoming; in the upper Colorado River drainage in New Mexico, Colorado, and Wyoming; isolated populations exist in endorheic basins in Utah and Nevada (Page and Burr 1991).

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 Cottus bairdii are found here.

StateFirst ObservedLast ObservedTotal HUCs with observations†HUCs with observations†
AZ194519733Havasu-Mohave Lakes; Lower Colorado; Lower Colorado Region
CA195019711Havasu-Mohave Lakes
CO198619861San Luis
NC197219721Upper Broad
UT197719771Utah Lake
VA194519452Middle New; Upper James
WY199519951Upper Wind

Table last updated 7/21/2024

† Populations may not be currently present.

Ecology: Mottled Sculpins are generally found in gravel or rocky rubble substrates in swift waters of headwaters, creeks, and small rivers. Occasionally in lakes, reservoirs, or springs in rocky substrate. They are benthic ambush predators, consuming primarily aquatic insect larvae (e.g., flies and midges), crustaceans, small fishes, and fish eggs (Etnier and Starnes 1993).

Means of Introduction: Bait bucket release in the Colorado River in Arizona, California, and Nevada. Miller (1952) and Miller and Lowe (1967) reported the use of this species as a bait fish in the lower Colorado River. The fish was introduced accidently into Colorado by the Colorado Division of Wildlife (Zuckerman and Behnke 1986); the pathway of introduction is unknown for North Carolina.

Status: Failed in Arizona, California, and Nevada. Minckley (1973) speculated it may be established in the lower Colorado River; however, it is not established there (Minckley, personal communication). Moyle (2002) does not mention this species from California. Established in North Carolina; failed in Colorado.

Impact of Introduction: Possible predator on young trout and eggs (Miller 1952).

Remarks: There is disagreement concerning native and introduced ranges of this species in North Carolina. Menhinick (1991) listed this species as probably introduced to the Broad River drainage. In contrast, Starnes (personal communication) believes that records of this species in the Broad drainage in North Carolina may have been the result of stream capture from the French Broad and is thus native. Additionally, Mottled Sculpin is considered a polytypic species complex, and it is likely that true Cottus bairdii (sensu stricto; species originally described from Ohio River area) does not occur in this drainage in North Carolia. Miller (1952) reported observations of an individual who saw a six-inch sculpin in Lake Havasu. This observation, based on the large size, may have been based on Gillichthys mirabilis, a species of goby (family Gobiidae), which is also commonly used as bait in that area.

References: (click for full references)

Becker, G.C. 1983. Fishes of Wisconsin. University of Madison Press, Madison, WI.

Etnier, D.A., and W.C. Starnes. 1993. The fishes of Tenneessee. University of Tennessee Press, Knoxville, TN.

Jenkins, R.E., and N.M. Burkhead. 1994. Freshwater Fishes of Virginia. American Fisheries Society, Bethesda, MD.

Menhinick, E.F. 1991. The freshwater fishes of North Carolina. North Carolina Wildlife Resources Commission. 227 pp.

Miller, R.R. 1952. Bait fishes of the lower Colorado River, from Lake Mead, Nevada, to Yuma, Arizona, with a key for identification. California Fish and Game 38:7-42.

Miller, R.R., and C.H. Lowe. 1967. Fishes of Arizona. 133-151 in C.H. Lowe, ed. The vertebrates of Arizona, part 2. University of Arizona Press, Tucson, AZ.

Minckley, W.L. 1973. Fishes of Arizona. Arizona Fish and Game Department. Sims Printing Company, Inc., Phoenix, AZ.

Moyle, P.B. 2002. Inland fishes of California. 2nd edition. University of California Press, Berkeley, CA.

Nelson, J.S., E.J. Crossman, H. Espinosa-Perez, L.T. Findley, C.R. Gilbert, R.N. Lea and J.D. Williams. 2004. Common and Scientific Names of Fishes from the United States, Canada and Mexico, Sixth Edition. American Fisheries Society Special Publication 29. Bethesda, MD.

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.

Wydoski, R.S., and R.R. Whitney. 1979. Inland fishes of Washington. University of Washington Press, Seattle, WA.

Zuckerman, L.D., and R.J. Behnke. 1986. Introduced fishes in the San Luis Valley, Colorado. 435-452 in R. H. Stroud, ed. Fish culture in fisheries management. Proceedings of a symposium on the role of fish culture in fisheries management at Lake Ozark, MO, March 31-April 3, 1985. American Fisheries Society, Bethesda, MD.

Other Resources:
FishBase Summary

Author: Pam Fuller, and Matt Neilson

Revision Date: 3/5/2012

Peer Review Date: 3/5/2012

Citation Information:
Pam Fuller, and Matt Neilson, 2024, Cottus bairdii Girard, 1850: U.S. Geological Survey, Nonindigenous Aquatic Species Database, Gainesville, FL, https://nas.er.usgs.gov/queries/FactSheet.aspx?speciesID=502, Revision Date: 3/5/2012, Peer Review Date: 3/5/2012, Access Date: 7/21/2024

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 [7/21/2024].

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