Effects of Habitat-Specific Primary Production on Fish Size, Biomass, and Production in Northern Oligotrophic Lakes

Abstract Ecological theory predicts that the relative distribution of primary production across habitats influence fish size structure and biomass production. In this study, we assessed individual, population, community-level consequences for brown trout ( Salmo trutta ) Arctic char Salvelinus alpinus variation in estimated habitat specific (benthic pelagic) total whole lake (GPP gross 27 northern oligotrophic lakes. We found higher contribution benthic to GPP was associated with community larger maximum mean sizes fish. At population level, species-specific responses differed. Increased Benthic correlated regardless being alone or sympatry, while responded positively pelagic Pelagic sympatric populations. lakes, both species related Whole . allopatric were proportion Our results highlight importance light-controlled further suggest ontogenetic asymmetry niche shifts may cause be more important than ecosystem size, biomass, Awareness relationships between light availability asymmetric resource favoring large allow cost-efficient informed management actions