Thymallus arcticus (Pallas, 1776)

Common Name: Arctic Grayling

Synonyms and Other Names:

Ryan Hagerty, U.S. Fish and Wildlife ServiceCopyright Info

Ryan Hagerty, U.S. Fish and Wildlife ServiceCopyright Info

Brian McKenna, Tanana Chiefs Conference - Fairbanks, AKCopyright Info

Identification: Scott and Crossman (1973); Morrow (1980); Page and Burr (1991). Grayling can be distinguished from all other salmonids by the presence of a large, sail-like dorsal fin. At one time T. arcticus was divided into four separate species: T. signifer, T. montanus, T. tricolor, and T. ontariensis. Thymallus signifer is now treated as synonymous with T. arcticus, and the others are considered subspecies of T. arcticus (Lee et al. 1980 et seq.).

Size: 76 cm (Page and Burr 1991)

Native Range: Widespread in Arctic drainages from Hudson Bay to Alaska and in Arctic and Pacific drainages to central Alberta and British Columbia; upper Missouri River drainage, Montana. Formerly in Great Lakes basin, Michigan. Also in Asia (Page and Burr 1991).

The only remaining natural, native remnant population in the continental United States is in Big Hole River, Montana (Wydoski and Whitney 2003). All other populations are the result of introductions or re-introductions.

Great Lakes Nonindigenous Occurrences: Grayling have been introduced into Alaska (Morrow 1980); Big Lake and the Salt and Verde drainages in Arizona (Miller and Lowe 1967; Minckley 1973; Lee et al. 1980 et seq.; Rinne 1995); at least 26 waterbodies in 11 counties, including the lower Klamath, Sacramento (Pit), San Joaquin, and northern Mojave drainages in California (Shebley 1917; Dill and Cordone 1997; Moyle 2002); Zimmerman Lake in the Cache la Poudre system, the North and South Platte rivers, the San Luis Valley in the Rio Grande headwaters, the Eagle and Frying Pan rivers on the west slope, and the Arkansas drainage in Colorado (Bowers 1901; Beckman 1952; Everhart and Seaman 1971; Ellis 1974; Morrow 1980; Wiltzius 1985; Zuckerman and Behnke 1986; Walker 1993; Rasmussen 1998); Housatonic drainage in Connecticut (Whitworth 1996); the Kootenai, Spokane, Salmon, Bear, and Snake (above and below the falls) drainages, and other independent drainages in Idaho (Bowers 1901; Linder 1963; Simpson and Wallace 1978; Lee et al. 1980 et seq.; Idaho Fish and Game 1990, 1996, 2012); the Maquoketa and Coon-Yellow systems in Iowa (Bowers 1901); unspecified locations in Maine (Kendall 1914); Ford Lake, Michigan (Hubbs and Lagler 1958); Twin Lake near Isabella in the Rainey headwaters, and several lakes in the Arrowhead region of the Baptism-Brule drainage, including Musquash Lake, Minnesota (Bowers 1901; Eddy and Underhill 1974; Phillips et al. 1982); unspecified locations in Missouri (Pflieger 1971); Glacier National Park, the Belly, Red Rock, Madison, Gallatin, upper Missouri-Dearborn, Sun, Clarks Fork Yellowstone, Pend Orielle, and Rock systems in Montana (Bowers 1901; Lee et al. 1980 et seq.; Cross et al. 1986; Holton 1990; Tilmant 1999); several unspecified streams in Nebraska (Jones 1963; Morris et al. 1974; Cross et al. 1986); high elevation lakes in the northern part of the state, Desert Creek, Ruby Valley, Steele Lake in Elko County, Nevada (Miller and Alcorn 1946; La Rivers 1962; Deacon and Williams 1984; Sigler and Sigler 1987); Long Pond in Benton (Hoover 1936), and Sunapee Lake (Bickford 1914), New Hampshire; the Canjilon area in New Mexico (Koster 1957; Sublette et al. 1990); unspecified areas of New York (Bickford 1914); upper Deschutes (Lee et al. 1980 et seq.) and Umatilla (Bowers 1901) systems, Oregon; the Atlantic basin (Susquehanna and/or Delaware drainage), Pennsylvania (Bean 1892); unspecified areas of South Dakota (Johnson 1937); lakes and streams in Duchesne, Summitt, Cache, and Daggett counties, and in the Uintah and Wasatch mountains, streams near Salt Lake City, Blind, Navajo, Lockawaxen, Caroly, Round, Sand, and Blue lakes, and Red Creek, Big Ells and Labaron reservoirs in Utah (Sigler and Miller 1963; Lee et al. 1980 et seq.; Sigler and Sigler 1987, 1996); Caspian Lake (Bowers 1901) and other unspecified mountainous areas in Vermont (Lee et al. 1980 et seq.; Morrow 1980; Cox, personal communication); below Philpott Reservoir, Virginia (Jenkins and Burkhead 1994); one mountain lake in Washington (Wydoski and Whitney 1979; Fletcher, personal communication); the Namekagon, Wolf, Brule, and Beartrap-Nemadji systems in Wisconsin (Bowers 1901; Becker 1983); and Yellowstone Lake, Bighorn, Wind, and Medicine Bow rivers, Big Sandy Reservoir, Jackson Lake, Babione Creek (upper Tongue), Beartooth Lake (Clarks Fork Yellowstone), and Frye Lake (Popo Agie), Wyoming (Johnson 1937; Baxter and Simon 1970; Lee et al. 1980 et seq.; Cross et al. 1986; DeLorme Mapping 1992; Gorges 1994; Hubert 1994).

Table 1. Great Lakes region nonindigenous occurrences, the earliest and latest observations in each state/province, 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 Thymallus arcticus are found here.

Full list of USGS occurrences

State/ProvinceYear of earliest observationYear of last observationTotal HUCs with observations†HUCs with observations†
Michigan188019252St. Joseph; Tittabawassee
Vermont190019001Lamoille River
Wisconsin190019382Beartrap-Nemadji; Wolf

Table last updated 9/30/2019

† Populations may not be currently present.

Ecology: Grayling generally inhabit clear, cold, high-altitude lakes and rivers (Behnke 2002; Wydoski and Whitney 2003). Spawning occurs in the spring, when water temperatures reach 45-50° F. Unlike most salmonids, grayling do not construct any sort of nest but spawn directly over gravel or rocky areas of smaller streams and tributaries (Behnke 2002). Diet primarily consists of aquatic and terrestrial invertebrates, zooplankton, small fishes, and occasionally fish eggs (Behnke 2002; Wydoski and Whitney 2003).

Means of Introduction: Authorized stocking for sportfishing. First stocked in Arizona in 1943 (Rinne 1995). First stocked in Connecticut in the 1870s (Whitworth 1996). Stocked in Nebraska in 1939 (Jones 1963). First stocked in southern Michigan in 1877 (Fukano et al. 1964).

Status: Established in several states, including Arizona (Rinne 1995). Reported from Colorado, Montana, Nevada, Oregon, and Vermont. Failed in Connecticut, Maine, Missouri, Nebraska, New Mexico, and Virginia. Extirpated from Pennsylvania.  Although largely extirpated from its native range within the Great Lakes basin, it is found in some inland lakes in the region that were not part of its original range.

Remarks: Native populations are considered extinct in Montana (Holton 1990) except for a remnant population in the Big Hole River (Wydoski and Whitney 2003).  The species has be re-stocked in the Red Rock, Madison, Gallatin and Sun drainages, as well as other locations. A relict population was present in the Great Lakes up until the 1930s, when it was extirpated due to competition with other introduced salmonids, habitat degradation, and fishing pressure (Hubbs and Lagler 1958). The Upper Missouri River population has been proposed to be classified as threatened or endangered under the Endangered Species Act (USFWS 2010).

References: (click for full references)

Baxter, G.T., and J.R. Simon. 1970. Wyoming fishes. Wyoming Game and Fish Department Bulletin 4, Cheyenne, WY.

Bean, T.H. 1892. The fishes of Pennsylvania, with descriptions of the species and notes on their common names, distribution, habits, reproduction, rate of growth and mode of capture. Report of the State Commissioners of Fisheries for the years 1889-90-91. Edwin K. Meyers, State Printer, Harrisburg, PA.

Beckman, W.C. 1952. Guide to the fishes of Colorado. University of Colorado Museum, Boulder, CO.

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

Behnke, R.J. 2002. Trout and salmon of North America. The Free Press, New York, NY.

Bickford, W.M. 1914. Notes on the Montana grayling. Transactions of the American Fisheries Society 43:153-155.

Bowers, G. M. 1901. Report of the commissioner of fish and fisheries for the year ending June 30, 1900. Part XXVI. U.S. Commission of Fish and Fisheries, Washington, D.C.

Cross, F.B., R.L. Mayden, and J.D. Stewart. 1986. Fishes in the western Mississippi basin (Missouri, Arkansas, and Red Rivers). 363-412 in C.H. Hocutt and E.O. Wiley, eds. The zoogeography of North American freshwater fishes. John Wiley and Sons, New York, NY.

Deacon, J.E., and J.E. Williams. 1984. Annotated list of the fishes of Nevada. Proceedings of the Biological Society of Washington 97(1):103-118.

DeLorme Mapping. 1992. Wyoming Atlas and Gazetteer. DeLorme Mapping, Freeport, ME.

Dill, W.A., and A.J. Cordone. 1997. History and status of introduced fishes in California, 1871-1996. California Department of Fish and Game Fish Bulletin, volume 178.

Eddy, S., and J.C. Underhill. 1974. Northern fishes, with special reference to the Upper Mississippi Valley, 3rd edition. University of Minnesota Press, Minneapolis, MN.

Ellis, M.M. 1974. Fishes of Colorado. University of Colorado Studies, Boulder, CO 11(1):1-136.

Everhart, W.H., and W.R. Seaman. 1971. Fishes of Colorado. Colorado Game, Fish and Parks Division, Denver, CO.

Fukano, K.G., H. Gowing, M.J. Hansen, and L.N. Allison. 1964. Introduction of exotic fish into Michigan. Michigan Department of Conservation, Institute of Fisheries Research, Ann Arbor, MI.

Gorges, M. 1994. Resident fish habitat management strategy for Wyoming. Bureau of Land Management, Wyoming State Office.

Holton, G.D. 1990. A field guide to Montana fishes. Montana Department of Fish, Wildlife and Parks, Helena, MT.

Hoover, E.E. 1936. Preliminary biological survey of some New Hampshire lakes. New Hampshire Fish and Game Department. Survey Report No. 1. Concord, NH.

Hubbs, C.L., and K.F. Lagler. 1958. Fishes of the Great Lakes region. University of Michigan Press, Ann Arbor, MI.

Hubert, W. 1994. Exotic fish. 158-174 in T.L. Parrish, and S.H. Anderson, eds. Exotic species manual. Wyoming Game and Fish Department, Laramie, WY.

Idaho Department of Fish and Game. 1990. Fisheries Management Plan 1991-1995. Appendix I - A list of Idaho fishes and their distribution by drainage. Idaho Department of Fish and Game.

Idaho Department of Fish and Game. 1996. Fisheries Management Plan 1996-2000. Idaho Department of Fish and Game.

Idaho Department of Fish and Game. 2012. Fish stocking information.

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

Johnson, H.E. 1937. Feeding Montana grayling fry. Progressive Fish Culturist 30:35-36.

Jones, D.J. 1963. A history of Nebraska's fisheries resources. Dingell-Johnson Federal Aid in Fish Restoration Project F-4-R Publication. Nebraska Game, Forestation and Parks Commission.

Kendall, W.C. 1914. An annotated catalogue of the fishes of Maine. Proceedings of the Portland Society of Natural History 3:1-198.

Koster, W.J. 1957. Guide to the fishes of New Mexico. University of New Mexico Press, Albuquerque, NM.

La Rivers, I. 1962. Fishes and fisheries of Nevada. Nevada State Print Office, Carson City, NV.

Lee, D.S., C.R. Gilbert, C.H. Hocutt, R.E. Jenkins, D.E. McAllister, and J.R. Stauffer, Jr. 1980. Atlas of North American freshwater fishes. North Carolina State Museum of Natural History, Raleigh, NC.

Linder, A.D. 1963. Idaho's alien fishes. Tebiwa 6(2):12-15.

Miller, R.R., and J.R. Alcorn. 1946. The introduced fishes of Nevada, with a history of their introduction. Transactions of the American Fisheries Society 73:173-193.

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.

Morris, J., L. Morris, and L. Witt. 1974. The fishes of Nebraska. Nebraska Game and Parks Commission, Lincoln, NE.

Morrow, J.E. 1980. The freshwater fishes of Alaska. Alaska Northwest Publishing Company, Anchorage, AK.

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

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

Pflieger, W.L. 1971. A distributional study of Missouri fishes. University of Kansas Museum of Natural History 20(3):225-570.

Phillips, G.L., W.D. Schmid, and J.C. Underhill. 1982. Fishes of the Minnesota region. University of Minnesota Press, Minneapolis, MN.

Rasmussen, J.L. 1998. Aquatic nuisance species of the Mississippi River basin. 60th Midwest Fish and Wildlife Conference, Aquatic Nuisance Species Symposium. December 7, 1998. Cincinnati, OH.

Rinne, J.N. 1995. The effects of introduced fishes on native fishes: Arizona, Southwestern United States. 149-159 in D.P. Philipp, J.M. Epifano, J.E. Marsden, J.E. Claassen, and R.J. Wolotina, Jr., eds. Protection of aquatic diversity. Proceedings of the World Fisheries Congress, Theme 3. Oxford & IBH Publishing Company, New Delhi.

Scott, W.B., and E.J. Crossman. 1973. Freshwater Fishes of Canada. Fisheries Research Board of Canada, Bulletin 184. Ottawa.

Shebley, W. H. 1917. History of the introduction of food and game fishes into the waters of California. California Fish and Game 3(1):3-10.

Sigler, W.F., and R.R. Miller. 1963. Fishes of Utah. Utah Department of Fish and Game, Salt Lake City, UT.

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.

Simpson, J., and R. Wallace. 1978. Fishes of Idaho. University of Idaho Press, Moscow, ID.

Sublette, J.E., M.D. Hatch, and M. Sublette. 1990. The fishes of New Mexico. University of New Mexico Press, Albuquerque, NM.

Tilmant, J.T. 1999. Management of nonindigenous aquatic fish in the U.S. National Park System. National Park Service.

U.S. Fish and Wildlife Service. 2010. Endangered and threatened wildlife and plants; revised 12-month finding to list the upper Missouri River distinct population segment of Arctic Grayling as endangered or threatened; proposed rule. Federal Register 50 CFR Part 17:54708-54753.

Whitworth, W.R. 1996. Freshwater fishes of Connecticut. State Geological and Natural History Survey of Connecticut, Bulletin 114.

Wiltzius, W.J. 1985. Fish culture and stocking in Colorado, 1872-1978. Division Report 12. Colorado Division of Wildlife.

Wydoski, R.S. and R.R. Whitney. 2003. Inland fishes of Washington. Second edition. University of Washington Press, Seattle, Washington.

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.

Author: Pam Fuller, Matt Cannister, and Matt Neilson

Contributing Agencies:

Revision Date: 8/28/2019

Peer Review Date: 11/5/2012

Citation for this information:
Pam Fuller, Matt Cannister, and Matt Neilson, 2020, Thymallus arcticus (Pallas, 1776): U.S. Geological Survey, Nonindigenous Aquatic Species Database, Gainesville, FL, and NOAA Great Lakes Aquatic Nonindigenous Species Information System, Ann Arbor, MI,, Revision Date: 8/28/2019, Peer Review Date: 11/5/2012, Access Date: 2/27/2020

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.