Incubation Temperature and Limits to the Arctic Distributions of Pacific Salmon: A Trait-Based Approach to Predicting Colonization and Possible Competition with Native Chars

Warming temperatures may be influencing distributional shifts in the Arctic, yet understanding regarding the ecological implications of these shifts is limited. Vagrant Chum and Pink Salmon appear to be increasing in abundance and distribution in the Canadian Arctic, and could colonize new habitats. Substrate-spawning salmonids in the Arctic share the requirement for hyporheic flow, creating the potential for interaction among the colonizing Chum or Pink Salmon and native riverine chars in spawning habitat. Potential species-specific differences, however, in optimal hyporheic temperature may spatially separate these fish both regionally and at the watershed level. A trait-based approach provides insight into the risk of interaction between colonizing Pacific salmon and native riverine chars in Arctic freshwater ecosystems by associating species-specific hyporheic temperatures to the mechanism of establishment for colonizers. Proactive monitoring strategies could integrate hyporheic temperature into current efforts to better understand and adapt to a dynamic Arctic ecosystem.