Percopsis omiscomaycus - (Walbaum, 1792)
Taxonomic Status: Accepted
Related ITIS Name(s): Percopsis omiscomaycus (Walbaum, 1792) (TSN 164409)
French Common Names: omisco
Unique Identifier: ELEMENT_GLOBAL.2.104223
Element Code: AFCLC01010
Informal Taxonomy: Animals, Vertebrates - Fishes - Bony Fishes - Other Bony Fishes
Kingdom Phylum Class Order Family Genus
Animalia Craniata Actinopterygii Percopsiformes Percopsidae Percopsis
Genus Size: B - Very small genus (2-5 species)
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Concept Reference
Concept Reference: 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. American Fisheries Society, Special Publication 20. 183 pp.
Concept Reference Code: B91ROB01NAUS
Name Used in Concept Reference: Percopsis omiscomaycus
Taxonomic Comments: The family Percopsidae, found only in North America, contains two species: the trout-perch (Percopsis omiscomaycus) and the sand roller (P. transmontana).
Conservation Status

NatureServe Status

Global Status: G5
Global Status Last Reviewed: 17Aug2015
Global Status Last Changed: 20Sep1996
Ranking Methodology Used: Ranked by inspection
Rounded Global Status: G5 - Secure
Reasons: Secure - widespread and abundant.
Nation: United States
National Status: N5 (05Dec1996)
Nation: Canada
National Status: N5 (17Aug2015)

U.S. & Canada State/Province Status
United States Alaska (S3), Connecticut (SX), District of Columbia (SH), Illinois (S2), Indiana (S2), Iowa (S3), Kentucky (S3), Maryland (SX), Massachusetts (SX), Michigan (S4), Minnesota (SNR), Missouri (S1?), Montana (S2), Nebraska (S1), New Jersey (SX), New York (S3), North Dakota (SNR), Ohio (S4), Pennsylvania (S4), South Dakota (S2), Utah (SNA), Vermont (S3), Virginia (SX), Washington (SNR), West Virginia (S3S4), Wisconsin (S5)
Canada Alberta (S5), British Columbia (S4), Manitoba (S5), Northwest Territories (S5), Nunavut (SU), Ontario (S5), Quebec (S4), Saskatchewan (S5), Yukon Territory (SU)

Other Statuses

IUCN Red List Category: LC - Least concern

NatureServe Global Conservation Status Factors

Range Extent: >2,500,000 square km (greater than 1,000,000 square miles)
Range Extent Comments: Atlantic and Arctic basins throughout most of Canada from Quebec to Yukon and British Columbia and south to the Potomac River drainage, Virginia; Yukon River drainage, Yukon and Alaska; Great Lakes and Mississippi River basins south to West Virginia, eastern Kentucky, southern Illinois, central Missouri, North Dakota, and northern Montana; locally common in lakes, uncommon throughout most of range (Page and Burr 1991).

Number of Occurrences: > 300
Number of Occurrences Comments: This species is represented by a large number of occurrences (subpopulations).

Population Size: >1,000,000 individuals
Population Size Comments: Total adult population size is unknown but presumably exceeds 1,000,000. The species is relatively abundant within its range in Canada and the lower 48 states (Mecklenburg et al. 2002). In Heming Lake, Manitoba, the adult fish population was estimated at 2,929 to 3,636 fish per hectare (Morrow 1980)

Number of Occurrences with Good Viability/Integrity: Many to very many (41 to >125)

Overall Threat Impact Comments: On a range-wide scale no major threats are known. In the southern part of the range, degradation of lakes and streams has negatively affected distribution and abundance.

Trout-perch are especially sensitive to aquatic pollution and sedimentation associated with row crop agriculture and channelization (Pflieger 1997). Fish exposed to pulp mill effluent on the Kapuskasing River, Ontario, showed a change in age structure that was likely driven by an increase in mortality (Gibbons et al. 1998). This species may also be temperature sensitive; summer die-offs in Minnesota lakes have been attributed to higher than average temperatures (Eddy and Underhill 1974). A marked decline in the Red Deer River, Alberta trout-perch population was attributed to the impacts of a dam built there (Nelson, pers. comm., in Bramblett 2005).

Short-term Trend Comments: Trend over the past 10 years or three generations is uncertain but likely relatively stable or slowly declining.

Long-term Trend: Decline of 30-50%
Long-term Trend Comments: Declines in area of occupancy, number of subpopulations, and abundance have occurred in the southern part of the range.

Other NatureServe Conservation Status Information

Global Range: (>2,500,000 square km (greater than 1,000,000 square miles)) Atlantic and Arctic basins throughout most of Canada from Quebec to Yukon and British Columbia and south to the Potomac River drainage, Virginia; Yukon River drainage, Yukon and Alaska; Great Lakes and Mississippi River basins south to West Virginia, eastern Kentucky, southern Illinois, central Missouri, North Dakota, and northern Montana; locally common in lakes, uncommon throughout most of range (Page and Burr 1991).

U.S. States and Canadian Provinces
Color legend for Distribution Map
Endemism: occurs (regularly, as a native taxon) in multiple nations

U.S. & Canada State/Province Distribution
United States AK, CTextirpated, DC, IA, IL, IN, KY, MAextirpated, MDextirpated, MI, MN, MO, MT, ND, NE, NJextirpated, NY, OH, PA, SD, UTexotic, VAextirpated, VT, WA, WI, WV
Canada AB, BC, MB, NT, NU, ON, QC, SK, YT

Range Map
No map available.

U.S. Distribution by County Help
State County Name (FIPS Code)
IA Clayton (19043)*, Lyon (19119)*, Sioux (19167)*
KY Allen (21003)*, Bath (21011)*, Boyd (21019), Campbell (21037)*, Carter (21043), Casey (21045)*, Elliott (21063), Fleming (21069)*, Floyd (21071), Greenup (21089), Jefferson (21111)*, Lawrence (21127)*, Lewis (21135), Oldham (21185), Rowan (21205)*, Shelby (21211)*
MA Berkshire (25003)*
MD Cecil (24015)*, Harford (24025)*, Montgomery (24031)*
MO Adair (29001)*, Boone (29019), Caldwell (29025), Callaway (29027)*, Cape Girardeau (29031), Carroll (29033), Chariton (29041), Cooper (29053), Daviess (29061), DeKalb (29063), Gasconade (29073)*, Grundy (29079), Harrison (29081), Jefferson (29099)*, Linn (29115), Livingston (29117)*, Macon (29121), Moniteau (29135), Montgomery (29139)*, Perry (29157)*, Pettis (29159)*, Putnam (29171), Schuyler (29197)*, St. Charles (29183)*, Sullivan (29211)
MT Glacier (30035)
NE Burt (31021), Thurston (31173)*
SD Codington (46029), Lincoln (46083), Minnehaha (46099), Moody (46101), Union (46127)*
VT Chittenden (50007)
* Extirpated/possibly extirpated
U.S. Distribution by Watershed Help
Watershed Region Help Watershed Name (Watershed Code)
01 Housatonic (01100005)+
02 Lake George (02010001), Winooski (02010003), Ausable (02010004), Lamoille (02010005), Great Chazy-Saranac (02010006), Missisquoi (02010007), Hudson-Hoosic (02020003)+, Mohawk (02020004), Middle Hudson (02020006), Rondout (02020007)*, Lehigh (02040106), Lower Susquehanna (02050306)+*, Upper Chesapeake Bay (02060001)+*, Chester-Sassafras (02060002)+*, Gunpowder-Patapsco (02060003)+*, Middle Potomac-Catoctin (02070008)+*
04 St. Louis (04010201), Beartrap-Nemadji (04010301), Bad-Montreal (04010302), Keweenaw Peninsula (04020103), Betsy-Chocolay (04020201), Lake Superior (04020300), Manitowoc-Sheboygan (04030101), Door-Kewaunee (04030102), Duck-Pensaukee (04030103)*, Oconto (04030104)*, Wolf (04030202), Lake Winnebago (04030203), Lower Fox (04030204), Little Calumet-Galien (04040001), Pike-Root (04040002), Boardman-Charlevoix (04060105), Lake Michigan (04060200), Lake St. Clair (04090002), Clinton (04090003), Ottawa-Stony (04100001), Lower Maumee (04100009), Cedar-Portage (04100010), Sandusky (04100011)*, Huron-Vermilion (04100012), Black-Rocky (04110001), Ashtabula-Chagrin (04110003), Grand (04110004), Chautauqua-Conneaut (04120101), Cattaraugus (04120102)*, Buffalo-Eighteenmile (04120103), Niagara (04120104)*, Lake Erie (04120200), Oak Orchard-Twelvemile (04130001)*, Upper Genesee (04130002), Irondequoit-Ninemile (04140101)*, Seneca (04140201), Oneida (04140202), Oswego (04140203), Chaumont-Perch (04150102), Upper St. Lawrence (04150301), Raquette (04150305)*, Lamoille River (04150405)+
05 Upper Allegheny (05010001), Conewango (05010002), Middle Allegheny-Tionesta (05010003), Middle Allegheny-Redbank (05010006), Lower Allegheny (05010009), Upper Ohio (05030101), Upper Ohio-Wheeling (05030106), Little Muskingum-Middle Island (05030201), Upper Ohio-Shade (05030202), Little Kanawha (05030203), Hocking (05030204), Tuscarawas (05040001)*, Mohican (05040002), Walhonding (05040003), Muskingum (05040004)*, Wills (05040005)*, Licking (05040006), Elk (05050007), Lower Kanawha (05050008), Upper Scioto (05060001), Lower Scioto (05060002), Paint (05060003)*, Lower Guyandotte (05070102), Lower Levisa (05070203)+, Big Sandy (05070204)+, Lower Great Miami (05080002)*, Whitewater (05080003), Raccoon-Symmes (05090101), Twelvepole (05090102), Little Scioto-Tygarts (05090103)+, Little Sandy (05090104)+, Ohio Brush-Whiteoak (05090201)+, Little Miami (05090202)*, Middle Ohio-Laughery (05090203)+*, Licking (05100101)+, Upper Green (05110001)+, Barren (05110002)+*, Silver-Little Kentucky (05140101)+, Salt (05140102)+, Blue-Sinking (05140104)
07 Upper Minnesota (07020001), Upper St. Croix (07030001), Namekagon (07030002), Lower St. Croix (07030005), Rush-Vermillion (07040001), Buffalo-Whitewater (07040003), La Crosse-Pine (07040006), Upper Chippewa (07050001), Flambeau (07050002), South Fork Flambeau (07050003), Jump (07050004), Lower Chippewa (07050005), Red Cedar (07050007), Coon-Yellow (07060001), Grant-Little Maquoketa (07060003)+*, Upper Wisconsin (07070001), Castle Rock (07070003), Lower Wisconsin (07070005), Flint-Henderson (07080104)*, Peruque-Piasa (07110009)+*, Kankakee (07120001), Upper Illinois (07120005), Lower Illinois-Senachwine Lake (07130001), Lower Illinois-Lake Chautauqua (07130003)*, Lower Illinois (07130011), Cahokia-Joachim (07140101)+*, Upper Mississippi-Cape Girardeau (07140105)+
09 Upper Souris (09010001), Lower Souris (09010003), Bois De Sioux (09020101), Upper Red (09020104), Lower Sheyenne (09020204), Sandhill-Wilson (09020301), Red Lakes (09020302), Red Lake (09020303), Lower Red (09020311), Pembina (09020313), Rainy Headwaters (09030001), St. Marys (09040001)+
10 St. Mary (10010002), Milk Headwaters (10050001)+, Lewis and Clark Lake (10170101)+*, Middle Big Sioux Coteau (10170201)+, Upper Big Sioux (10170202), Lower Big Sioux (10170203)+, Rock (10170204)+, Blackbird-Soldier (10230001)+, Floyd (10230002)*, Little Sioux (10230003), Boyer (10230007)*, East Nishnabotna (10240003)*, Upper Grand (10280101)+, Thompson (10280102)+, Lower Grand (10280103)+, Upper Chariton (10280201)+, Lower Chariton (10280202)+, Little Chariton (10280203)+*, Lower Gasconade (10290203)+, Lower Missouri-Moreau (10300102)+, Lamine (10300103)+, Lower Missouri (10300200)+*
+ Natural heritage record(s) exist for this watershed
* Extirpated/possibly extirpated
U.S. Distribution by Watershed (based on multiple information sources) Help
Ecology & Life History
Basic Description: A small freshwater fish.
Reproduction Comments: Usually spawns in spring, but spawning may extend into late summer in some lakes. Most spawners are age I or II (Becker 1983, Scott and Crossman 1973).
Habitat Type: Freshwater
Non-Migrant: Y
Locally Migrant: Y
Long Distance Migrant: N
Mobility and Migration Comments: May migrate between lake and spawning stream (Scott and Crossman 1973).
Riverine Habitat(s): BIG RIVER, CREEK, MEDIUM RIVER, Moderate gradient, Pool
Lacustrine Habitat(s): Deep water, Shallow water
Habitat Comments: Typically in lakes but also in deep flowing pools of creeks and small to large rivers; usually over sand (Page and Burr 1991). Normally in deep waters by day, moves into shallows at night (Becker 1983). Spawns in shallow rocky or gravelly streams or over sand or gravel bars or among rocks in lakes. Often spawns in streams in spring and returns to lake after spawning.
Adult Food Habits: Invertivore, Piscivore
Immature Food Habits: Invertivore, Piscivore
Food Comments: Young feed on zooplankton to greater extent than do larger fishes, which feed on insects, crustaceans, and other invertebrates, mainly benthic species. Larger individuals may feed on fishes in winter (Scott and Crossman 1973, Becker 1983).
Adult Phenology: Crepuscular, Nocturnal
Immature Phenology: Crepuscular, Nocturnal
Length: 15 centimeters
Economic Attributes Not yet assessed
Management Summary Not yet assessed
Population/Occurrence Delineation
Use Class: Not applicable
Minimum Criteria for an Occurrence: Occurrences are based on evidence of historical presence, or current and likely recurring presence, at a given location. Such evidence minimally includes collection or reliable observation and documentation of one or more individuals (including eggs and larvae) in appropriate habitat.
Separation Barriers: Dam lacking a suitable fishway; high waterfall; upland habitat.
Separation Distance for Unsuitable Habitat: 10 km
Separation Distance for Suitable Habitat: 10 km
Separation Justification: Separation distance is arbitrary. Because of the difficulty in defining suitable versus unsuitable habitat, especially with respect to dispersal, and to simplify the delineation of occurrences, a single separation distance is used regardless of habitat quality.
Date: 25Jun2001
Author: Hammerson, G.
Population/Occurrence Viability
U.S. Invasive Species Impact Rank (I-Rank) Not yet assessed
NatureServe Conservation Status Factors Edition Date: 08Jan2008
NatureServe Conservation Status Factors Author: Jansen, A., T. A. Gotthardt, and G. Hammerson
Element Ecology & Life History Edition Date: 14Sep1993
Element Ecology & Life History Author(s): Hammerson, G.

Zoological data developed by NatureServe and its network of natural heritage programs (see Local Programs) and other contributors and cooperators (see Sources).

  • Aquin, P. 1999. Évaluation de la situation des groupes taxonomiques des poissons du Québec. Ministère de l'Environnement et de la Faune. 9 pages.

  • Atton, F.M. and J.J. Merkowsky. 1983. Atlas of Saskatchewan Fish. Saskatchewan Department of Parks and Renewable Resources, Fisheries Branch Technical Report 83-2. 281pp.

  • Bramblett, R.G. 2005. Trout-perch. Montana's fish species of special concern. American Fisheries Montana Chapter. Available online at: Accessed 9/23/05.

  • Eddy, S. and J. C. Underhill. 1974. Northern fishes, with special reference to the Upper Mississippi Valley, 3rd edition. University of Minnesota Press, Minneapolis, Minnesota. 414 pp

  • Fisheries Branch. 1991. Fish Species Distributions in Saskatchewan. Report 91-7. Saskatchewan Parks and Renewable Resources, Fisheries Branch. Regina. 102pp.

  • Gibbons, W. N., K. R. Munkittrick, M. E. McMaster, and W. D .Taylor.1998. Monitoring aquatic environments receiving industrial effluents using small fish species 2: comparison between responses of trout-perch (Percopsis omiscomaycus) and white sucker (Catostomus commersoni) downstream of a pulp mill. Environmental Toxicology and Chemistry 17: 2238-2245.

  • House, R. and L. Wells. 1973. Age, growth, spawning season and fecundity of the trout-perch, Percopsis omiscomaycus, in southeastern Lake Michigan. Journal of the Fisheries Research Board of Canada 30(8):1221-1225.

  • Kinney, E. C. 1950. The life history of the trout perch, Percopsis omiscomaycus (Walbaum). in western Lake Erie. Ohio State University, Columbus, Ohio. MS Thesis. 75 pp.

  • Legendre, V. et J.F. Bergeron. 1977. Liste des poissons d' eau douce du Québec. MLCP, Service Aménage. Expl. Faune. Rap. dact. 6

  • Mecklenburg, C. W., T. A. Mecklenburg, and L. K. Thorsteinson. 2002. Fishes of Alaska. American Fisheries Society, Bethesda, Maryland. xxxvii + 1,037 pp.

  • Morrow, J.E. 1980. The freshwater fishes of Alaska. Alaska Northwest Publishing Company, Anchorage, AK. 248 pp.

  • Muth, S. E. and D. C. Tarter. 1975. Reproductive biology of the trout perch, Percopsis omiscomaycus (Walbaum), in Beech Fork of Twelvepole Creek, Wayne County, West Virginia. American Midland Naturalist 93(2): 434-439.

  • 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. American Fisheries Society, Special Publication 29, Bethesda, Maryland. 386 pp.

  • Page, L. M., H. Espinosa-Pérez, L. T. Findley, C. R. Gilbert, R. N. Lea, N. E. Mandrak, R. L. Mayden, and J. S. Nelson. 2013. Common and scientific names of fishes from the United States, Canada, and Mexico. Seventh edition. American Fisheries Society, Special Publication 34, Bethesda, Maryland.

  • Page, L. M., and B. M. Burr. 1991. A field guide to freshwater fishes: North America north of Mexico. Houghton Mifflin Company, Boston, Massachusetts. 432 pp.

  • Page, L. M., and B. M. Burr. 2011. Peterson field guide to freshwater fishes of North America north of Mexico. Second edition. Houghton Mifflin Harcourt, Boston. xix + 663 pp.

  • Pflieger, W. L. 1997a. The fishes of Missouri. Revised edition. Missouri Department of Conservation, Jefferson City. vi + 372 pp.

  • 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. American Fisheries Society, Special Publication 20. 183 pp.

  • Saskatchewan Environment and Resource Management. 1996. The Fisheries Regulations being Chapter F-16.1 Reg 1 (effective 9 May 1995) as ammended by Saskatchewan Regulations 13/96.

  • Scott, W. B., and E. J. Crossman. 1973. Freshwater fishes of Canada. Fisheries Research Board of Canada, Bulletin 184. 966 pp.

  • Scott, W.B. and E.J. Crossman. 1979. Freshwater Fishes of Canada. Fisheries Research Board of Canada. Bull. 84. 966pp.

References for Watershed Distribution Map
  • Becker, G. C. 1983. Fishes of Wisconsin. University of Wisconsin Press, Madison. 1,052 pp.

  • Burr, B. M., and M. L. Warren, Jr. 1986a. Distributional atlas of Kentucky fishes. Kentucky Nature Preserves Commission, Scientific and Technical Series No. 4, Frankfort, Kentucky. 398 pp.

  • Cooper, E. L. 1983. Fishes of Pennsylvania and the northeastern United States. Pennsylvania State University Press, University Park. 243 pp.

  • Fago, D. 2000. Relative abundance and distribution of fishes in Wisconsin. Fish Distribution Database to year 2000. Wisconsin Department of Natural Resources.

  • Harlan, J. R., E. B. Speaker, and J. Mayhew. 1987. Iowa fish and fishing. Iowa Conservation Commission, Des Moines, Iowa. 323 pp.

  • Holton, G. D., and H. E. Johnson. 1996. A field guide to Montana fishes. 2nd edition. Montana Fish, Wildlife and Parks, Montana State Parks and wildlife Interpretive Association, Helena, Montana. 104 pp.

  • Jenkins, R. E., and N. M. Burkhead. 1994. Freshwater fishes of Virginia. American Fisheries Society, Bethesda, Maryland. xxiii + 1079 pp.

  • 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, North Carolina. i-x + 854 pp.

  • Pflieger, W. L. 1975. The fishes of Missouri. Missouri Department of Conservation. Columbia, Missouri. viii + 343 pp.

  • Smith, C. L. 1985. The inland fishes of New York State. New York State Department of Environmental Conservation. Albany, New York, xi + 522 pp.

  • Smith, P. W. 1979. The fishes of Illinois. University of Illinois Press, Urbana. 314 pp.

  • State Natural Heritage Data Centers. 1996a. Aggregated element occurrence data from all U.S. state natural heritage programs, including the Tennessee Valley Authority, Navajo Nation and the District of Columbia. Science Division, The Nature Conservancy.

  • Stauffer, J. R., Jr., J. M. Boltz, and L. R. White. 1995. The fishes of West Virginia. Proceedings of the Academy of Natural Sciences of Philadelphia 146:1-389.

  • Trautman, M. B. 1981. The fishes of Ohio. Second edition. Ohio State University Press, Columbus, Ohio. 782 pp.

  • Whitworth, W. R., P. L. Berrien, and W. T. Keller. 1976. Freshwater fishes of Connecticut. Bulletin of the Connecticut Geological and Natural History Survey 101. vi + 134 pp.

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