Riverscape organisation, anthropogenic disturbances and salmonid habitat

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Salmon fisheries play a role in the regional economies along both coasts of Canada while trout angling is an important recreational industry in the Canadian interior. Substantial funds are currently spent on the rehabilitation and management of freshwater salmonid (salmon, trout) habitat, under threat from damming, improper forestry and farm practices, highway construction, etc.  To minimize habitat degradation or to be more effective in rehabilitation, it is important to understand where the most productive or most sensitive habitats  are located along a river. This research proposes to apply novel models of river landscape structure (sedimentary link models) to better answer these questions.Salmon production in freshwaters can critically depend on a complex juxtaposition of different stream habitat types within a  watershed: lakes, pool-riffle cobble reaches, boulder rapid reaches etc.; insuring, within distances that individual fish can  swim as they grow, clean, gravel-cobble reaches for reproduction and fry rearing, boulder-rich sections for rearing of older salmon parr, and finally thermal refugia and backchannel zones that allow survival through periods of heat stress in summer and ice-related stress in winter. The proposed research program uses novel geomatics, air photo and field techniques to understand the geomorphic controls on salmonid habitat acting across these spatial scales and applying this knowledge to habitat management and conservation. A major research focus is to test hypotheses concerning the effects on salmon abundances of details of riverscape structure (length  and organisation of 'sedimentary links' along valleys, spacing and distribution of bedrock canyons, of boulder rich zones, of   cool water tributaries, etc).