HomeFish encyclopediaRay-finned fishesSalmonsSalmonidsRound whitefish Round whitefish (Prosopium cylindraceum) Scientific name: Prosopium cylindraceum Pennant, 1784 The Round whitefish (Prosopium cylindraceum) is a freshwater fish of the family Salmonidae. BiologyInhabits shallow areas of lakes and clear streams, rarely entering brackish water. Also in rivers with swift current and stony bottom. Migration is limited to movements associated with spawning. Epipelagic. Feeds on benthic invertebrates and occasionally on fishes and fish eggs. One specimen taken from a depth of 218.9 m in eastern Lake Superior, off Grand Marais, Michigan.Source: FishBase, licensed CC BY-NC 4.0. Species factsScientific nameProsopium cylindraceumFamilySalmonidae (Salmonids)OrderSalmoniformes (Salmons)ClassActinopterygii (Ray-finned fishes)Maximum length59.0Common length28.6Depth range72 m (236 ft)EnvironmentFreshwater; brackish; demersal; potamodromous; depth range ? - 72 m, usually ? - 37 mClimateTemperateDistributionNorth America: Arctic and Pacific drainages from western Hudson Bay in Canada to Alaska and northern British Columbia, Canada; Arctic and Atlantic drainages from Labrador in Canada to Connecticut, USA and west through St. Lawrence-Great Lakes basin in Canada-USA (except Lake Erie). Northern Asia: widely distributed in Siberian rivers.Conservation status (IUCN)Not EvaluatedThreat to humansHarmlessUsesFisheries: minor commercial; gamefish: yesResilienceLow, minimum population doubling time 4.5 - 14 years (tm=5-7; tmax=16; Fec=1,000) SourcesTaxonomy, distribution and biology data: FishBase (Froese, R. and D. Pauly, eds.), licensed CC BY-NC 4.0.Last updated 27 September 2026