E-Fauna BC: Electronic Atlas of the Wildlife of British Columbia

Catostomus catostomus (Forster, 1773)
Longnose Sucker
Family: Catostomidae
Photo of species

© Jamie Fenneman  Email the photographer   (Photo ID #3217)

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Source: Distribution map provided by Don McPhail for E-Fauna BC
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The Longnose Sucker is a habitat generalist that is found in cool waters throughout BC where it is primarily an interior species (McPhail 2007). Spawning migrations occur in the early spring (mid-June in the Peace and Cariboo), are temperature driven, and occur earlier than other species of sucker (McPhail 2007). Three forms are recognized in BC (McPhail 2007), with one form, the Chehalis form (Salish Sucker), red-listed in BC and listed as endangered by COSEWIC. The BC Conservation Data Centre lists the Salish Sucker as Catostomus sp.4.

Species Information

Dorsal spines (total): 0; Dorsal soft rays (total): 9 - 11; Anal spines: 0; Anal soft rays: 7; Vertebrae: 45 - 47. Distinguished by the sucking mouth located on the ventral sides of the head and thick papillose lips (Ref. 27547). Gill rakers short; lateral line complete, inconspicuous; caudal tips slightly rounded (Ref. 27547). Adults may be reddish brown, dark brassy green or black above, paler on the lower sides, with the ventral parts white; young fish are usually dark gray with small black spots; breeding males are usually dark above with a brilliant reddish stripe along each side, while females are greenish gold to copper, with a less brilliant red stripe; breeding males show prominent tubercles on the rays of the anal and caudal fins and also on the head (Ref. 27547).

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

Identification and Subspecies Information

The three distinctive forms of the Longnose Sucker recognized in BC by McPhail (2007) are:

1) Longnose Sucker ('normal' form)
Refer to the text above for the general description of the species, its biology, and its range.

2) Longnose Sucker ('dwarf' form)
"A set of geographically scattered 'dwarf' populations that breed at smaller sizes" is present in BC (McPhail 2007).

3) Longnose Sucker (Chehalis form)--the Salish Sucker (listed as Catostomus sp. 4 by the BC Conservation Data Centre)
"An undescribed genetically and morphologically distinct form of the Longnose Sucker (Catastomus catastomus)" (Eric Taylor, pers. com. 2011).


Species Biology

Found in clear, cold, deep water of lakes and tributary streams; occasionally found in brackish water in the Arctic (Ref. 5723). Moves from lakes into inlet streams or from slow, deep pools into shallow, gravel-bottomed portions of streams to spawn (Ref. 27547). Feeds on benthic invertebrates (Ref. 1998). Young are preyed upon by other fishes and fish-eating birds; while adults in spawning streams are taken by mammals, osprey and eagles (Ref. 1998)

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


BC Distribution and Notes

This is the most widely distributed sucker in British Columbia. There are “dwarf” populations scattered around the province. The ecological factors associated with these populations of small suckers are unknown but in at least one lake (now rehabilitated) small-bodied and large-bodied longnose suckers once coexisted. In B.C., one small-bodied form — the Salish sucker — is restricted to the lower Fraser Valley. Genetically and morphologically, it is slightly, but consistently, different from other northwestern longnose suckers.

Source: Information provided by Don McPhail for E-Fauna BC.
Global Distribution

North America: throughout most of Canada and Alaska; Atlantic Slope south to Delaware River drainage in New York, USA; Great Lakes basin; upper Monongahela River drainage in Maryland and West Virginia, USA; Missouri River drainage south to Nebraska and Colorado, USA. Also in Arctic basin of Siberia in Russia. Occurs in Columbia River System (Molly Hallock, pers. Comm.).

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

Status Information

Origin StatusProvincial StatusBC List
(Red Blue List)
NativeS5YellowNot Listed
BC Ministry of Environment: BC Species and Ecosystems Explorer--the authoritative source for conservation information in British Columbia.

Additional Notes

This is a nocturnal species that spawns in riffles in the spring (Pearson and Healey 2012).

Additional Range and Status Information Links

Additional Photo Sources

Species References

DFO 2008. Aquatic Species at Risk. Salish Sucker. Fisheries and Oceans Canada. Available online.

McPhail, J. D. 2007. The Freshwater Fishes of British Columbia. The University of Alberta Press. Edmonton.

Pearson, Mike. 1999. The Biology and Management of the Salish Sucker and Nooksack Dace. Proc. Biology and Management of Species and Habitats at Risk. Kamloops, B.C., 15–19 Feb. 1999. Available online.

Pearson, Mike and Healey, M.C.2012. Species at Risk and Local Government: a Primer for BC. Stewardship Centre of British Columbia, Courtenay BC. Available online.

Taylor Eric. 2011. Personal Communication. Department of Zoology, University of British Columbia.

General References

Recommended citation: Author, Date. Page title. In Klinkenberg, Brian. (Editor) 2021. E-Fauna BC: Electronic Atlas of the Fauna of British Columbia [efauna.bc.ca]. Lab for Advanced Spatial Analysis, Department of Geography, University of British Columbia, Vancouver. [Accessed: 2024-06-15 3:41:19 AM]
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