Influence of the Landscape Template on Chemical and Physical Habitat for Brown Trout Within a Boreal Stream Network

We used the distribution of stream-dwelling brown trout ( Salmo trutta ) in a 67 km 2 boreal catchment to explore importance environmental organizing factors at range spatial scales, including whole-catchment characteristics derived from map data, and stream reach chemical physical characteristics. Brown were not observed any sites characterized by pH < 5.0 during spring snowmelt episode, matching published toxicity thresholds. distributions patchy even less acidic regions network, positively associated with glaciofluvial substrate negatively fine sand/silty sediments. A multivariate model only explained 43% variation densities, while models local site habitat or chemistry 33 25%, respectively. At scale, apparently played primary role this acidity placing an additional restriction excluding headwater streams. Much strength characteristics-fish association could be correlation catchment-scale landscape These results, consistent concept multiple hierarchical filters regulating fish species, underline considering scales both environments when attempting manage restore streams for trout.