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.

Salmo letnica
Salmo letnica
(Ohrid trout)

Copyright Info
Salmo letnica (Karaman, 1924)

Common name: Ohrid trout

Synonyms and Other Names: Lake Ohrid brown trout, Pestani trout, koran

Taxonomy: available through www.itis.govITIS logo

Identification: Ohrid trout has a fusiform body with silvery coloration with numerous black spots, especially above the lateral line (dorsal region). The species has distinct red spots (when present) along the lateral line (Kottelat and Fryhof 2007). The trout has numerous spots on the caudal fin making it distinct from Brown trout (Salmo trutta).

Ohrid trout is part of the Brown trout (Salmo trutta) complex (Phillips et al., 2000; Balkan Trout Restoration Group 2005).

Size: 76.0 cm total length (Crawford 1993); max. published weight: 6.5 kg (International Game Fish Association 1991).

Native Range: The Ohrid trout is native to Ohrid Lake located in the Republic of Macedonia in Europe (formerly Yugoslavia) (Robins et al. 1991). Lake Ohrid is Europe's oldest lake and is believed to have been formed as early as during the Tertiary period at least 4 million years ago (Balkan Trout Restoration Group 2005) .

Hydrologic Unit Codes (HUCs) Explained
Interactive maps: Point Distribution Maps

Nonindigenous Occurrences: The Ohrid trout was stocked in Parvin Lake, Big Creek Reservoir, and Turquoise Lake in Colorado, in 1969 (Courtenay and Hensley 1979; Wiltzius 1985; Courtenay et al. 1991), seven lakes in northern Minnesota, including Strawberry Lake, Chester Lake, and Big Trout Lake (MacCrimmon and Campbell 1969; Stroud 1969; Courtenay and Hensley 1979a; Radonski et al. 1984); an unspecified locality in Montana (Courtenay et al. 1991); Watauga Reservoir (= Ripshin Lake) (Courtenay and Hensley 1979a; Etnier and Starnes 1993) and South Holston Reservoir (Starnes, personal communication), Tennessee; and a few reservoirs in Wyoming, including Viva Naughton Reservoir on the Green River, lakes near Casper, and the North Platte River (MacCrimmon and Campbell 1969; Courtenay and Hensley 1979; Courtenay et al. 1991; Hubert 1994; Wyoming Game and Fish, Fish Division 1997).

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 Salmo letnica are found here.

StateFirst ObservedLast ObservedTotal HUCs with observations†HUCs with observations†
CO196919693Arkansas Headwaters; Cache La Poudre; Lower Dolores
MN1965200820Baptism-Brule; Beaver-Lester; Big Fork; Cloquet; Crow; Crow Wing; Eastern Wild Rice; Kettle; Leech Lake; Little Fork; Long Prairie; Lower Minnesota; Lower St. Croix; Mississippi Headwaters; Otter Tail; Pine; Platte-Spunk; Prairie-Willow; Rainy Headwaters; St. Louis
TN197119972South Fork Holston; Watauga, North Carolina, Tennessee
WY196520115Blacks Fork; Middle North Platte-Casper; North Platte; Nowood; Pathfinder-Seminoe Reservoirs

Table last updated 6/16/2024

† Populations may not be currently present.

* HUCs are not listed for states where the observation(s) cannot be approximated to a HUC (e.g. state centroids or Canadian provinces).

Ecology: Ohrid trout is a lentic (lake) species and has been known to live in depths of 60-80 m within a lake (Crivelli 2006). Juveniles trout feed on zooplankton, while adults prey on zooplankton and fish (Kottelat and Fryhof 2007). This species of trout is a single spawning species (Jordanova 2004) which attains first sexual maturity at 5-6 years. Ohrid trout spawn in January-February (in their native range) in littoral and sublittoral areas (Kottelat and Fryhof 2007). 

Means of Introduction: The Ohrid trout was brought into the United States by the U.S. Fish and Wildlife Service and shipped to a federal hatchery in Iowa and a state hatchery in Minnesota (Courtenay and Hensley 1979). In 1965, eggs from Yugoslavia were hatched in the United States; young fish were released into several small lakes in northern Minnesota in 1968 and 1969 (Stroud 1969). Ohrid trout have been stocked in Tennessee since 1971 (Etnier and Starnes 1993). The species was first stocked in Colorado in 1969 (Wiltzius 1985).

Status: Introductions into most of these states failed. Repeatedly stocked in Tennessee with no evidence of reproduction yet (Etnier and Starnes 1993). Courtenay and Hensley (1979) report that even though there has been no reproduction, spawning has been observed in Tennessee.

Impact of Introduction: The impacts of this species are currently unknown, as no studies have been done to determine how it has affected ecosystems in the invaded range. The absence of data does not equate to lack of effects. It does, however, mean that research is required to evaluate effects before conclusions can be made.

Remarks: A state record-sized fish was taken from the North Platte River in Wyoming in 1986 (Wyoming Game and Fish, Fish Division 1997).

The Ohrid trout faces extinction in its native lakes due to pollution, invasive species and overfishing. The warning comes from Balkan scientists who say even a proposed five-year commercial fishing ban won't be enough to save the species (Crivelli 2006).

References: (click for full references)

Balkan Trout Restoration Group. 2005. Ohrid Trout. http://www.balkan-trout.com/index.htm. Created on 01/01/2005. Accessed on 07/11/2019.

Courtenay, W.R., Jr., and D.A. Hensley. 1979. Survey of introduced non-native fishes. Phase I Report. Introduced exotic fishes in North America: status 1979. Report Submitted to National Fishery Research Laboratory, U.S. Fish and Wildlife Service, Gainesville, FL.

Courtenay, W.R., Jr., D.P. Jennings, and J.D. Williams. 1991. Appendix 2: exotic fishes. 97-107 in Robins, C.R., R.M. Bailey, C.E. Bond, J.R. Brooker, E.A. Lachner, R.N. Lea, and W.B. Scott. Common and scientific names of fishes from the United States and Canada, 5th edition. American Fisheries Society Special Publication 20. American Fisheries Society, Bethesda, MD.

Crivelli, A.J. 2006. Salmo letnica. The IUCN Red List of Threatened Species . http://www.iucnredlist.org/details/19858/0. Created on 10/01/2017. Accessed on 07/11/2019.

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

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.

Jordanova, M. 2004. The liver in female Salmo letnica Kar. (Teleostei, Salmonidae) during the reproductive cycle: a microscopic study of the natural population of Lake Ohrid. Unpublished Ph.D. dissertation. University St. Kiril and Metodij, Skopje, Macedonia.

Kottelat, M., and J. Freyhof. 2007. Handbook of European freshwater fishes. Publications Kottelat, Cornol, Switzerland.

MacCrimmon, H.R. and J.S. Campbell. 1969. World distribution of brook trout, Salvelinus fontinalis. Journal of the Fisheries Reserearch Board of Canada. 26:1699-1725.

Phillips, R.B., Matsuoka, M.P., Konon, I. and Reed, K.M. 2000. Phylogenetic analysis of mitochondrial and nuclear sequences supports inclusion of Acantholingua ohridana in the genus Salmo. Copeia 2:546-550.

Radonski, G.C., N.S. Prosser, R.G. Martin, and R.H. Stroud. 1984. Exotic fishes and sport fishing. 313-321 in W.R. Courtenay, Jr., and J.R. Stauffer, eds. Distribution, biology and management of exotic fishes. Johns Hopkins University Press, Baltimore, MD.

Robins, C.R., R.M. Bailey, C.E. Bond, J.R. Brooker, E.A. Lachner, R.N. Lea, and W.B. Scott. 1991. Common and scientific names of fishes from the United States and Canada, 5th edition. American Fisheries Society Special Publication 20. American Fisheries Society, Bethesda, MD.

Stefanovic, D. 1966. Racial and ecological study of the Ohrid salmonids. NOLIT Publishing House, Belgrade, Yugoslavia translated/published for U.S. Department of Interior & National Science Foundation, Washington, DC.

Stroud, R. H. 1969. Ohrid trout tests. Sport Fishing Institute Bulletin 210:7-8.

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

FishBase Summary

Author: Fuller, P. and Daniel, W.M.

Revision Date: 7/11/2019

Peer Review Date: 7/11/2019

Citation Information:
Fuller, P. and Daniel, W.M., 2024, Salmo letnica (Karaman, 1924): U.S. Geological Survey, Nonindigenous Aquatic Species Database, Gainesville, FL, https://nas.er.usgs.gov/queries/FactSheet.aspx?SpeciesID=925, Revision Date: 7/11/2019, Peer Review Date: 7/11/2019, Access Date: 6/16/2024

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 [6/16/2024].

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