Resource partitioning in a spring spawning freshwater fish assemblage dominated by catostomids (Catostomus commersoni, C. catostomus)

• Main Author: Dion, René
• Format: Thesis
• Language: English
• Published: McGill University 1992
• Subjects: Fishes > Québec (Province) > Ecology; Resource partitioning (Ecology) > Québec (Province); White sucker; Longnose sucker > Québec (Province); Longnose sucker
• Online Access: http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=60700

For three consecutive years, I monitored the spring stream residency and spawning of five species of fishes using a tributary stream of the Gouin Reservoir (north central Quebec). Timing of spawning of the distantly related species was different whereas the spawning activity of the closely related suckers overlapped in time and space. Intra- and inter-specific egg predation by the two sucker species was observed as well as predation by lake whitefish (Coregonus clupeaformis) on sucker eggs. Synchronisation of the spawning of the suckers may allow them to "swamp" egg predators with drifting eggs. Abundance of spawning fish was affected by water management practices in the reservoir. When water levels were low, fewer fish of all species had access to the stream possibly because of the development of rapids. The courtship behavior of the two sucker species was described and compared in the same period, to determine if behavioral isolating mechanisms which prevented hybridization existed.