Platygobio gracilis - (Richardson, 1836)
Flathead Chub
Synonym(s): Hybopsis gracilis
Taxonomic Status: Accepted
Related ITIS Name(s): Platygobio gracilis (Richardson, 1836) (TSN 163882)
French Common Names: méné à tête plate
Unique Identifier: ELEMENT_GLOBAL.2.105832
Element Code: AFCJB57010
Informal Taxonomy: Animals, Vertebrates - Fishes - Bony Fishes - Minnows and Carps
Kingdom Phylum Class Order Family Genus
Animalia Craniata Actinopterygii Cypriniformes Cyprinidae Platygobio
Genus Size: A - Monotypic genus
Check this box to expand all report sections:
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: Platygobio gracilis
Taxonomic Comments: Removed from the genus Hybopsis and returned to the monotypic genus Platygobio by Mayden (1989) and by Coburn and Cavender (1992). This treatment was followed by Sublette et al. (1990) and in the 1991 AFS checklist (Robins et al. 1991).
Conservation Status

NatureServe Status

Global Status: G5
Global Status Last Reviewed: 17Aug2015
Global Status Last Changed: 17Sep1997
Ranking Methodology Used: Ranked by inspection
Rounded Global Status: G5 - Secure
Reasons: Widespread in central North America; common and secure in the north, declining at the southern margin of the range, due in large part to the impacts of dams/reservoirs and stream channelization.
Nation: United States
National Status: N5 (05Dec1996)
Nation: Canada
National Status: N5 (22Dec2017)

U.S. & Canada State/Province Status
Due to latency between updates made in state, provincial or other NatureServe Network databases and when they appear on NatureServe Explorer, for state or provincial information you may wish to contact the data steward in your jurisdiction to obtain the most current data. Please refer to our Distribution Data Sources to find contact information for your jurisdiction.
United States Arkansas (SH), Colorado (S3), Illinois (SX), Iowa (S3), Kansas (S1), Kentucky (S1), Minnesota (SNA), Mississippi (S1?), Missouri (S1), Montana (S5), Nebraska (S5), New Mexico (S4), North Dakota (SNR), Oklahoma (S1?), South Dakota (S5), Tennessee (S2S3), Texas (S2), Wyoming (S5)
Canada Alberta (S4S5), British Columbia (S4), Manitoba (S5), Northwest Territories (S5), Saskatchewan (S3S4), Yukon Territory (SU)

Other Statuses

IUCN Red List Category: LC - Least concern

NatureServe Global Conservation Status Factors

Range Extent Comments: Mackenzie and Saskatchewan river drainages, and Lake Winnipeg drainage, in Yukon, Northwest Territories, Manitoba, Saskatchewan, Alberta, and British Columbia; Missouri-Mississippi river basin from southern Alberta and Montana to Louisiana; upper Rio Grande (including Pecos) drainage, New Mexico; common in north, restricted to Mississippi River proper from Illinois south; localized in Arkansas River drainage in Oklahoma, Texas, and New Mexico (Page and Burr 1991).

Number of Occurrences: 81 to >300
Number of Occurrences Comments: Hundreds of occurrences.

Population Size: 10,000 to >1,000,000 individuals
Population Size Comments: Total abundance is unknown, but certainly exceeds 10,000 individuals.

Overall Threat Impact Comments: Threatened only in the southern part of the range. Dams/reservoirs are detrimental. Dewatering and stream channelization have contributed to the decline in Kansas (Collins et al. 1995). Backwater productivity may contribute importantly to the prey base, so reduction in natural flooding patterns may be detrimental (Fisher et al. 2002). Extirpated from the upper Arkansas River in Colorado, apparently due to pollution from mining; recolonization after water quality improvement may be prevented by a large water diversion structure (Woodling 1985). Tolerant of organic enrichment of streams (Woodling 1985).

Short-term Trend: Decline of 10-30%
Short-term Trend Comments: Has decreased in abundance in the lower Missouri River as a result of human-caused changes in the river (e.g., reservoir construction); could be extirpated from the lower river if trends continue (Pflieger and Grace 1987). A 1994 survey in the Missouri River in Missouri indicated a further reduction in distribution and abundance compared to 1983 data (see Figg and Bessken 1995). Grady and Milligan (1998) and Gelwicks et al. (1996) also noted declines in the impounded and channelized segments of the Missouri River.

Other NatureServe Conservation Status Information

Inventory Needs: Occurrences in the southern part of the range should be regularly reinventoried.

Protection Needs: Populations in the southern part of the range should be protected from detrimental impacts of reservoirs.

Global Range: Mackenzie and Saskatchewan river drainages, and Lake Winnipeg drainage, in Yukon, Northwest Territories, Manitoba, Saskatchewan, Alberta, and British Columbia; Missouri-Mississippi river basin from southern Alberta and Montana to Louisiana; upper Rio Grande (including Pecos) drainage, New Mexico; common in north, restricted to Mississippi River proper from Illinois south; localized in Arkansas River drainage in Oklahoma, Texas, and New Mexico (Page and Burr 1991).

U.S. States and Canadian Provinces

Due to latency between updates made in state, provincial or other NatureServe Network databases and when they appear on NatureServe Explorer, for state or provincial information you may wish to contact the data steward in your jurisdiction to obtain the most current data. Please refer to our Distribution Data Sources to find contact information for your jurisdiction.
Color legend for Distribution Map
Endemism: occurs (regularly, as a native taxon) in multiple nations

U.S. & Canada State/Province Distribution
United States AR, CO, IA, ILextirpated, KS, KY, MNexotic, MO, MS, MT, ND, NE, NM, OK, SD, TN, TX, WY
Canada AB, BC, MB, NT, SK, YT

Range Map
No map available.

U.S. Distribution by County Help
State County Name (FIPS Code)
AR Crittenden (05035), Desha (05041), Mississippi (05093)
CO Las Animas (08071)
IA Sac (19161)*, Woodbury (19193)*
IL Alexander (17003)*
KS Atchison (20005)*, Cheyenne (20023)*, Doniphan (20043), Douglas (20045)*, Finney (20055)*, Hamilton (20075), Jefferson (20087)*, Jewell (20089)*, Kearny (20093)*, Leavenworth (20103), Morton (20129)*, Nemaha (20131), Republic (20157)*, Seward (20175)*, Wyandotte (20209)*
KY Ballard (21007), Fulton (21075)*
MO Andrew (29003), Atchison (29005), Boone (29019), Buchanan (29021), Callaway (29027), Cape Girardeau (29031)*, Carroll (29033), Chariton (29041), Cole (29051), Cooper (29053), Franklin (29071), Gasconade (29073)*, Holt (29087), Howard (29089), Jackson (29095)*, Jefferson (29099)*, Lafayette (29107)*, Miller (29131), Mississippi (29133), Moniteau (29135), Montgomery (29139), Nodaway (29147)*, Osage (29151), Pemiscot (29155)*, Perry (29157)*, Platte (29165), Ray (29177)*, Saline (29195), Scott (29201)*, St. Charles (29183), St. Louis (29189), Ste. Genevieve (29186), Warren (29219)
ND Emmons (38029), McKenzie (38053), Mountrail (38061), Williams (38105)
NE Blaine (31009), Boone (31011), Boyd (31015), Brown (31017), Buffalo (31019), Burt (31021), Cass (31025), Cedar (31027), Cuming (31039), Custer (31041), Dakota (31043), Dixon (31051), Dodge (31053), Douglas (31055), Holt (31089), Hooker (31091), Howard (31093), Keya Paha (31103), Knox (31107), Nance (31125), Nemaha (31127), Otoe (31131), Platte (31141), Richardson (31147), Rock (31149), Sarpy (31153), Sherman (31163), Thomas (31171), Valley (31175)
NM Bernalillo (35001)*, Colfax (35007), De Baca (35011)*, Guadalupe (35019)*, Harding (35021), Mora (35033), Quay (35037), Rio Arriba (35039)*, San Miguel (35047)*, Sandoval (35043)*, Santa Fe (35049)*, Socorro (35053)*, Taos (35055)*, Union (35059), Valencia (35061)*
OK Blaine (40011)*, Caddo (40015)*, Canadian (40017)*, Cimarron (40025), Greer (40055), Kay (40071), Kingfisher (40073), Osage (40113)
SD Custer (46033), Jackson (46071), Mellette (46095), Pennington (46103), Shannon (46113), Todd (46121), Tripp (46123)
TX Armstrong (48011), Hemphill (48211)*, Hutchinson (48233)*, Oldham (48359)*
* Extirpated/possibly extirpated
U.S. Distribution by Watershed Help
Watershed Region Help Watershed Name (Watershed Code)
05 Lower Ohio (05140206)+
07 North Raccoon (07100006)+*, Peruque-Piasa (07110009)+, Cahokia-Joachim (07140101)+, Meramec (07140102)+*, Upper Mississippi-Cape Girardeau (07140105)+*, Big Muddy (07140106), Lower Kaskaskia (07140204)*
08 Lower Mississippi-Memphis (08010100)+, Obion (08010202)+*, Lower Mississippi-Helena (08020100)+, New Madrid-St. Johns (08020201)*, Lower Mississippi-Natchez (08060100), Lower Mississippi-Baton Rouge (08070100)
10 Upper Missouri (10030101), Upper Missouri-Dearborn (10030102), Marias (10030203), Teton (10030205), Bullwhacker-Dog (10040101), Judith (10040103), Fort Peck Reservoir (10040104), Big Dry (10040105), Little Dry (10040106), Upper Musselshell (10040201), Middle Musselshell (10040202), Lower Musselshell (10040205), Middle Milk (10050004), Peoples (10050009), Whitewater (10050011), Lower Milk (10050012), Frenchman (10050013), Beaver (10050014), Rock (10050015), Porcupine (10050016), Prarie Elk-Wolf (10060001), Redwater (10060002), Poplar (10060003), Charlie-Little Muddy (10060005)+, Big Muddy (10060006), Clarks Fork Yellowstone (10070006), Upper Yellowstone-Pompeys Pillar (10070007), Pryor (10070008), Upper Wind (10080001), Little Wind (10080002), Lower Wind (10080005), Upper Bighorn (10080007), Nowood (10080008), Greybull (10080009), Big Horn Lake (10080010), Dry (10080011), Shoshone (10080014), Lower Bighorn (10080015), Little Bighorn (10080016), Upper Tongue (10090101), Lower Tongue (10090102), Upper Powder (10090202), Salt (10090204), Crazy Woman (10090205), Clear (10090206), Middle Powder (10090207), Little Powder (10090208), Lower Powder (10090209), Mizpah (10090210), Lower Yellowstone-Sunday (10100001), Big Porcupine (10100002), Rosebud (10100003), Lower Yellowstone (10100004)+, O'fallon (10100005), Lake Sakakawea (10110101)+, Upper Little Missouri (10110201), Boxelder (10110202), Middle Little Missouri (10110203), Beaver (10110204), Lower Little Missouri (10110205), Upper Cheyenne (10120103), Lance (10120104), Angostura Reservoir (10120106), Beaver (10120107), Middle Cheyenne-Spring (10120109)+, Rapid (10120110)+, Middle Cheyenne-Elk (10120111)+, Upper Belle Fourche (10120201), Lower Belle Fourche (10120202), Upper Lake Oahe (10130102)+, Lower Lake Oahe (10130105), Knife (10130201), Upper Heart (10130202), Lower Heart (10130203), Upper Cannonball (10130204), Lower Cannonball (10130206), South Fork Grand (10130302), Grand (10130303), Lower Moreau (10130306), Fort Randall Reservoir (10140101), Upper White (10140201)+, Middle White (10140202)+, Little White (10140203)+, Lower White (10140204), Ponca (10150001), Upper Niobrara (10150003), Middle Niobrara (10150004)+, Keya Paha (10150006)+, Lower Niobrara (10150007)+, Lewis and Clark Lake (10170101)+, Lower Big Sioux (10170203), Middle North Platte-Casper (10180007)*, Glendo Reservoir (10180008)*, Lower North Platte (10180014), Middle Platte-Buffalo (10200101), Wood (10200102), Middle Platte-Prairie (10200103)+, Lower Platte-Shell (10200201)+, Lower Platte (10200202)+, Upper Middle Loup (10210001)+, Dismal (10210002)+, Lower Middle Loup (10210003)+, South Loup (10210004)+, Mud (10210005), Loup (10210009)+, Lower Elkhorn (10220003)+, Blackbird-Soldier (10230001)+, Little Sioux (10230003), Monona-Harrison Ditch (10230004), Maple (10230005), Big Papillion-Mosquito (10230006)+, Boyer (10230007)+, Keg-Weeping Water (10240001)+, West Nishnabotna (10240002), East Nishnabotna (10240003), Nishnabotna (10240004), Tarkio-Wolf (10240005)+, Little Nemaha (10240006)+, South Fork Big Nemaha (10240007)+, West Nodaway (10240009), Nodaway (10240010)+*, Independence-Sugar (10240011)+, Platte (10240012)+*, One Hundred and Two (10240013)+*, North Fork Republican (10250002), South Fork Republican (10250003)+*, Upper Republican (10250004), Harlan County Reservoir (10250009), Lower Sappa (10250011), Beaver (10250014), Middle Republican (10250016)+, Lower Republican (10250017)*, Delaware (10270103)+, Lower Kansas (10270104)+, Lower Big Blue (10270205)*, Little Chariton (10280203)+, Lower Missouri-Crooked (10300101)+, Lower Missouri-Moreau (10300102)+, Lamine (10300103)+, Blackwater (10300104)*, Lower Missouri (10300200)+
11 Upper Arkansas (11020002), Fountain (11020003), Upper Arkansas-Lake Meredith (11020005)*, Huerfano (11020006), Apishapa (11020007), Upper Arkansas-John Martin (11020009)*, Purgatoire (11020010)+, Middle Arkansas-Lake Mckinney (11030001)+, Arkansas-Dodge City (11030003)*, Coon-Pickerel (11030004)*, Cimarron headwaters (11040001)+, Upper Cimarron (11040002)+, North Fork Cimarron (11040003)*, Upper Cimarron-Liberal (11040006)+*, Lower Cimarron-Skeleton (11050002)+, Kaw Lake (11060001)+, Canadian headwaters (11080001)+, Cimarron (11080002)+, Upper Canadian (11080003)+, Mora (11080004)+, Conchas (11080005)+, Upper Canadian-Ute Reservoir (11080006)+, Ute (11080007)+*, Revuelto (11080008)+, Lake Meredith (11090105)+*, Middle Canadian-Spring (11090106)+*, Lower Canadian-Deer (11090201), Lower Canadian-Walnut (11090202)+, Upper Beaver (11100101)+, Upper Prairie Dog Town Fork Red (11120103)+, Lower Salt Fork Red (11120202)+
13 Upper Rio Grande (13020101)+, Rio Chama (13020102)+, Rio Grande-Santa Fe (13020201)+, Jemez (13020202)+, Rio Grande-Albuquerque (13020203)+, Rio Puerco (13020204), Elephant Butte Reservoir (13020211)+, Pecos headwaters (13060001)+, Upper Pecos (13060003)+
+ 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 fish.
Reproduction Comments: Relies on flood flows to spawn successfully (Collins et al. 1995). Spawns after rivers have subsided after peak flow, when the temperature is warmer and the bottom is more stable, July-August in Montana, Kansas, and Iowa, when temperature reaches about 23-25 C in Montana. Pflieger (1975) stated that spawning may occur in early spring because chubs less than one inch long were collected in Missouri in late May. Sexually mature at age 2 in Iowa, 4 in Canada (Gould 1985).
Habitat Type: Freshwater
Non-Migrant: N
Locally Migrant: N
Long Distance Migrant: N
Riverine Habitat(s): BIG RIVER, Low gradient, MEDIUM RIVER, Moderate gradient
Special Habitat Factors: Benthic
Habitat Comments: Turbid flowing (moderate to strong current) waters in main channels of small to large rivers; in shallow to fairly deep water over mud, rock, or sand. In Kansas, usually in shallow pools but also in strong current over clean sand bottoms (Collins et al. 1995). May move into smaller streams to spawn (Scott and Crossman 1973).
Adult Food Habits: Invertivore
Immature Food Habits: Invertivore
Food Comments: Opportunistic; eats aquatic and terrestrial insects and some algae (Olund and Cross 1961).
Length: 32 centimeters
Economic Attributes Not yet assessed
Management Summary Not yet assessed
Population/Occurrence Delineation
Group Name: Medium Cyprinids

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: 15 km
Separation Distance for Suitable Habitat: 15 km
Separation Justification: Data on dispersal and other movements generally are not available. In some species, individuals may migrate variable distances between spawning areas and nonspawning habitats.

Separation distances (in aquatic kilometers) for cyprinids are arbitrary but reflect the presumption that movements and appropriate separation distances generally should increase with fish size. Hence small, medium, and large cyprinids, respectively, have increasingly large separation distances. Separation distance reflects the likely low probability that two occupied locations separated by less than many kilometers of aquatic habitat would represent truly independent populations over the long term.

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.

Occupied locations that are separated by a gap of 15 km or more of any aquatic habitat that is not known to be occupied represent different occurrences. However, it is important to evaluate seasonal changes in habitat to ensure that an occupied habitat occurrence for a particular population does not artificially separate spawning areas and nonspawning areas as different occurrences simply because there have been no collections/observations in an intervening area that may exceed the separation distance.

Date: 21Sep2004
Author: Hammerson, G.
Population/Occurrence Viability
U.S. Invasive Species Impact Rank (I-Rank) Not yet assessed
NatureServe Conservation Status Factors Edition Date: 05Mar2003
NatureServe Conservation Status Factors Author: Hammerson, G.
Element Ecology & Life History Edition Date: 22Sep1997
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).

  • Allen, C. R., S. Demarais, and R. S. Lutz. 1994. Red imported fire ant impact on wildlife: an overview. The Texas Journal of Science 46(1):51-59.

  • Andersen, M.D. and B. Heidel. 2011. HUC-based species range maps. Prepared by Wyoming Natural Diversity Database for use in the pilot WISDOM application operational from inception to yet-to-be-determined date of update of tool.

  • Anderson, Allison A., C. Hubbs, K. O. Winemiller, and R. J. Edwards. 1995. Texas freshwater fish assemblages following three decades of environmental change. The Southwest Naturalist 40(3):314-321.

  • 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.

  • Beauvais, Gary P. 2006. Addendum to Flathead chub (Platygobio gracilis): a technical conservation assessment. Reports prepared for the USDA Forest Service - Rocky Mountain Region (R2) by the Wyoming Natural Diversity Database - University of Wyoming, Laramie, Wyoming.



  • Coburn, M. M., and T. M. Cavender. 1992. Interrelationships of North American cyprinid fishes. Pages 328-373 in R.L. Mayden, editor. Systematics, historical ecology, and North American freshwater fishes. Stanford University Press, Stanford, California. xxvi + 969 pp.

  • Collins, J. T., S. L. Collins, J. Horak, D. Mulhern, W. Busby, C. C. Freeman, and G. Wallace.1995. An Illustrated Guide to Endangered or Threatened Species in Kansas. University Press of Kansas, Wichita, Kansas.

  • Ellis, M. M. 1914. Fishes of Colorado. University of Colorado Studies, Boulder. Vol. XI. 136 pp.

  • Etnier, David A. and Wayne C. Starnes. 1993. The Fishes of Tennessee. University of Tennessee Press, Knoxville. 681 pp.

  • Figg, D. E., and C. M. Bessken. 1995[?]. Missouri Department of Conservation wildlife diversity report: July 1994 - June 1995. v + 104 pp. [perhaps date is 1996]

  • Fisher, S. J., D. W. Willis, M. M. Olson, and S. C. Krentz. 2002. Flathead chubs, Platygobio gracilis, in the upper Missouri River: the biology of a species at risk in an endangered habitat. Canadian Field-Naturalist 116:26-41.

  • Gelwicks, G. T., K. Graham, D. Galat, and G. D. Novinger. 1996. Final report: status survey for sicklefin chub, sturgeon chub, and flathead chub in the Missouri River, Missouri. Missouri Department of Conservation, Columbia.

  • General Status, Environment Canada. 2015. Manitoba fish species and subnational ranks proposed by DFO.

  • Gould, W. 1985. Aspects of the biology of the flathead chub (Hybopsis gracilis) in Montana. Great Basin Naturalist 45: 332-336.

  • Grady, J. M., and J. Milligan. 1998. Status of selected cyprinid species at historic lower Missouri River sampling sites. U.S. Fish and Wildlife Service, Fisheries Assistance Office Report, Columbia, Missouri.

  • Herkert, Jim. 1998. Proposed additions, deletions, and changes to the Illinois List of Threatened and Endangered Animals. 101st ESPB Meeting, August 21, 1998. 16pp.

  • Matthews, W. J., and D. C. Heins, editors. 1987. Community and evolutionary ecology of North American stream fishes. Univ. Oklahoma Press, Norman. viii + 310 pp.

  • Mayden, R. L. 1989. Phylogenetic studies of North American minnows, with emphasis on the genus Cyprinella (Teleostei: Cypriniformes). University of Kansas Museum of Natural History Miscellaneous Publication (80):1-189.

  • 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.


  • Olund, L. J., and F. B. Cross. 1961. Geographic variation in the North American cyprinid fish Hybopsis gracilis. University of Kansas Museum of Natural History Publications 13(7):323-348.


  • 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. and T. B. Grace. 1987. Changes in the fish fauna of the lower Missouri River, 1940-1983. Pages 166-181 in W. J. Matthews and D. C Heins (editors). Community and Evolutionary Ecology of North American Stream Fishes. University of Oklahoma Press, Norman, Oklahoma.

  • 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.

  • Ryke, N., D. Winters, L. McMartin and S. Vest. 1994. Threatened, Endangered and Sensitive Species of the Pike and San Isabel National Forests and Comanche and Cimarron National Grasslands. May 25, 1994.

  • 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, Ottawa. 966 pp.

  • Woodling, J. 1985. Colorado's Little Fish: A Guide to the Minnows and Other Lesser Known Fishes in the State of Colorado. Colorado Division of Wildlife, Denver.

  • Woodling, J. 1985. Colorado's little fish: a guide to the minnows and other lesser known fishes in the state of Colorado. Colorado Division of Wildlife, Denver. 77 pp.

References for Watershed Distribution Map
  • Baxter, G. T., and J. R. Simon. 1970. Wyoming fishes. Wyoming Game and Fish Department, Cheyenne, Wyoming, 168 pp.

  • Cross, F. B., and J. T. Collins. 1995. Fishes in Kansas. Second Edition, revised. University of Kansas Museum of Natural History. xvii + 315 pp.

  • Douglas, N. H. 1974. Freshwater fishes of Louisiana. Claitor's Publishing Division, Baton Rouge, Louisiana. 443 pp.

  • Etnier, D. A., and W. C. Starnes. 1993. The fishes of Tennessee. University of Tennessee Press, Knoxville, Tennessee. xiv + 681 pp.

  • 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.

  • 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.

  • Robison, H. W. and T. M. Buchanan. 1988. Fishes of Arkansas. The University of Arkansas Press, Fayetteville, Arkansas. 536 pp.

  • Ross, S. T., and W. M. Brenneman. 1991. Distribution of freshwater fishes in Mississippi. Freshwater Fisheries Report No. 108. D-J Project Completion Report F-69. Mississippi Department of Wildlife and Freshwater Fisheries and Parks. Jackson, Mississippi. 548 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.

  • Sublette, J. E., M. D Hatch, and M. Sublette. 1990. The fishes of New Mexico. University New Mexico Press, Albuquerque, New Mexico. 393 pp.

Use Guidelines & Citation

Use Guidelines and Citation

The Small Print: Trademark, Copyright, Citation Guidelines, Restrictions on Use, and Information Disclaimer.

Note: All species and ecological community data presented in NatureServe Explorer at were updated to be current with NatureServe's central databases as of March 2018.
Note: This report was printed on

Trademark Notice: "NatureServe", NatureServe Explorer, The NatureServe logo, and all other names of NatureServe programs referenced herein are trademarks of NatureServe. Any other product or company names mentioned herein are the trademarks of their respective owners.

Copyright Notice: Copyright © 2018 NatureServe, 4600 N. Fairfax Dr., 7th Floor, Arlington Virginia 22203, U.S.A. All Rights Reserved. Each document delivered from this server or web site may contain other proprietary notices and copyright information relating to that document. The following citation should be used in any published materials which reference the web site.

Citation for data on website including State Distribution, Watershed, and Reptile Range maps:
NatureServe. 2018. NatureServe Explorer: An online encyclopedia of life [web application]. Version 7.1. NatureServe, Arlington, Virginia. Available (Accessed:

Citation for Bird Range Maps of North America:
Ridgely, R.S., T.F. Allnutt, T. Brooks, D.K. McNicol, D.W. Mehlman, B.E. Young, and J.R. Zook. 2003. Digital Distribution Maps of the Birds of the Western Hemisphere, version 1.0. NatureServe, Arlington, Virginia, USA.

Acknowledgement Statement for Bird Range Maps of North America:
"Data provided by NatureServe in collaboration with Robert Ridgely, James Zook, The Nature Conservancy - Migratory Bird Program, Conservation International - CABS, World Wildlife Fund - US, and Environment Canada - WILDSPACE."

Citation for Mammal Range Maps of North America:
Patterson, B.D., G. Ceballos, W. Sechrest, M.F. Tognelli, T. Brooks, L. Luna, P. Ortega, I. Salazar, and B.E. Young. 2003. Digital Distribution Maps of the Mammals of the Western Hemisphere, version 1.0. NatureServe, Arlington, Virginia, USA.

Acknowledgement Statement for Mammal Range Maps of North America:
"Data provided by NatureServe in collaboration with Bruce Patterson, Wes Sechrest, Marcelo Tognelli, Gerardo Ceballos, The Nature Conservancy-Migratory Bird Program, Conservation International-CABS, World Wildlife Fund-US, and Environment Canada-WILDSPACE."

Citation for Amphibian Range Maps of the Western Hemisphere:
IUCN, Conservation International, and NatureServe. 2004. Global Amphibian Assessment. IUCN, Conservation International, and NatureServe, Washington, DC and Arlington, Virginia, USA.

Acknowledgement Statement for Amphibian Range Maps of the Western Hemisphere:
"Data developed as part of the Global Amphibian Assessment and provided by IUCN-World Conservation Union, Conservation International and NatureServe."

NOTE: Full metadata for the Bird Range Maps of North America is available at:

Full metadata for the Mammal Range Maps of North America is available at:

Restrictions on Use: Permission to use, copy and distribute documents delivered from this server is hereby granted under the following conditions:
  1. The above copyright notice must appear in all copies;
  2. Any use of the documents available from this server must be for informational purposes only and in no instance for commercial purposes;
  3. Some data may be downloaded to files and altered in format for analytical purposes, however the data should still be referenced using the citation above;
  4. No graphics available from this server can be used, copied or distributed separate from the accompanying text. Any rights not expressly granted herein are reserved by NatureServe. Nothing contained herein shall be construed as conferring by implication, estoppel, or otherwise any license or right under any trademark of NatureServe. No trademark owned by NatureServe may be used in advertising or promotion pertaining to the distribution of documents delivered from this server without specific advance permission from NatureServe. Except as expressly provided above, nothing contained herein shall be construed as conferring any license or right under any NatureServe copyright.
Information Warranty Disclaimer: All documents and related graphics provided by this server and any other documents which are referenced by or linked to this server are provided "as is" without warranty as to the currentness, completeness, or accuracy of any specific data. NatureServe hereby disclaims all warranties and conditions with regard to any documents provided by this server or any other documents which are referenced by or linked to this server, including but not limited to all implied warranties and conditions of merchantibility, fitness for a particular purpose, and non-infringement. NatureServe makes no representations about the suitability of the information delivered from this server or any other documents that are referenced to or linked to this server. In no event shall NatureServe be liable for any special, indirect, incidental, consequential damages, or for damages of any kind arising out of or in connection with the use or performance of information contained in any documents provided by this server or in any other documents which are referenced by or linked to this server, under any theory of liability used. NatureServe may update or make changes to the documents provided by this server at any time without notice; however, NatureServe makes no commitment to update the information contained herein. Since the data in the central databases are continually being updated, it is advisable to refresh data retrieved at least once a year after its receipt. The data provided is for planning, assessment, and informational purposes. Site specific projects or activities should be reviewed for potential environmental impacts with appropriate regulatory agencies. If ground-disturbing activities are proposed on a site, the appropriate state natural heritage program(s) or conservation data center can be contacted for a site-specific review of the project area (see Visit Local Programs).

Feedback Request: NatureServe encourages users to let us know of any errors or significant omissions that you find in the data through (see Contact Us). Your comments will be very valuable in improving the overall quality of our databases for the benefit of all users.