Six field trials were conducted in two streams to compare the survival, growth, movement, and distribution of young-of-year Assinica strain and Temiscamie strain brook trout Salvelinusfontinalis 15-91 d after stocking. No consistent differences between strains in recovery after stocking or in growth were detected; however, movement and distribution within streams differed consistently between strains. Approximately four Temiscamie to one Assinica fish moved downstream 2-15 h after stocking. At the conclusion of five trials, the strains were dissimilarly distributed within streams (distribution was not assessed in the sixth trial): a large proportion of Assinica fish were found in the most upstream section of the streams, whereas a large proportion of Temiscamie fish were found in the most downstream section. These differences in movement and distribution may be related to the origins of the strains in large lake systems in Quebec, where spawning occurs in inlet and outlet streams. Assinica fish, which have a probable outlet origin and which moved upstream in this investigation, may be better suited for stocking in areas downstream of where brook trout are to be established. Conversely, their probable inlet origin and demonstrated downstream movement make Temiscamie fish candidates for stocking in upstream areas.
Brook trout (Salvelinus fontinalis) fry are susceptible to high mortality in acidified waters because of their low tolerance to acidic conditions and the potential occurrence of this life stage with episodic acidification associated with snowmelt. Prior to snowmelt, equal numbers of Assinica and Temiscamie strain fry were placed into enclosures. Twelve days after stocking, no consistent differences between strains were observed in survival, distribution, or ion composition. No fry of either strain survived in enclosures placed in shallow water (pH 4.8; 0.7 m depth). Fifty to 100% of fry of both strains survived in enclosures placed in deep water (pH 6.3; > 2.0 m depth). Fry survival in long enclosures that extended from shallow to deep water was 80–99%. Within long enclosures, both strains were recovered in higher densities from middle and deep sections of the enclosures than from shallow sections. High fry survival and non-random distributions in the long enclosures indicated that both strains were able to avoid lethal, nearshore waters during spring snowmelt by moving to deeper water.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.