Prioritization of Problem Culverts for Restoration Planning and Management: An Application and Comparison of Novel Techniques to Forested Boreal Freshwaterscapes

Alberta is a province with a wealth of natural resources, including vast expanses of harvestable timber and natural gas, as well as the majority of Canada’s oil reserves. In west-central Alberta, extraction of these resources has increased dramatically in recent years and caused landscape-level changes, predominantly from forest harvest and the development of road networks. Culverted road-stream crossings in particular (the most commonly installed structure on small stream in Alberta) can decrease habitat quality and disrupt stream network connectivity. As the repair or removal of problem culverts is an expensive endeavor, systematic methods for their prioritization are essential for the efficient allocation of restoration dollars. Here we assess the applicability of recently developed prioritization models (i.e. budget optimization, heuristics) that maximizes habitat availability for stream resident and potadromous fish in two Albertan watersheds. Each watershed is experiencing increasing levels of industrial resource extraction and contain important habitat for species of special concern (e.g. Arctic Grayling, Bull Trout). Alternative methods for quantifying stream connectivity and species-specific habitat suitability weighting are compared to assess differences in optimal restoration decisions for differing conservation priorities. Cost-benefit curves from these watersheds can be used to minimize overall restoration costs to achieve particular management objectives.