| Abstract/Description or Keywords |
In the face of climate change in the Pacific Northwest resulting in longer and more severe droughts in southern BC watersheds, stream rearing trout and salmon stocks are likely to experience reduced productivity due to declines in habitat quantity and quality. Impact mechanisms include changes in growth rates, thermal mortality, oxygen stress, changes in prey density and changes in interspecific and intraspecific competition. To address this issue, BC Conservation Foundation working with Ministry of Environment continued feasibility assessments of potential stream flow improvement projects in east coast Vancouver Island watersheds in partnership with DFO, First Nations, local governments, Ducks Unlimited Canada and community stewards. Projects since 2006 have included structural modifications or operational refinements to existing storage sites as well as new designs at locations where potential biological benefits are high, impacts are low, implementation is determined to be cost effective, and sufficient partner funding exists. In addition to modeling expected fish production benefits, activities undertaken by BCCF and sub-contracted experts included environmental impact assessments (plants, fish, amphibians, birds, as required), extensive stakeholder consultation, hydrologic studies, conceptual and design engineering, and licensing. Focusing on mainstems and sub-basins between Victoria and Port Hardy, flow improvements are designed to increase wild production of trout and salmon by providing elevated seasonal base flows and maintaining and/or increasing the area and quality of summer rearing habitat. Target species are mainly stream rearing salmonids including steelhead and cutthroat trout and coho salmon. Flow improvements may also benefit summer and early fall migrants such as adult summer run steelhead, pink salmon and Chinook salmon. Without investments to improve base flows, stocks will be less able to cope with stochastic population declines or support traditional sport fisheries and may need additional protection or more costly mitigation to ensure conservation levels are met. During 2009/10, this projects objective was to bring at least two of seven high priority candidate sites to the implementation phase, and advance several others closer to completion stages. Storage feasibility was essentially completed at Keogh Lake and at Upper Quinsam/Wokas Lakes, though implementation of only the former will likely proceed in 2010. BC Hydros prioritized project list for fiscal 2010/11 does not include implementation of negative storage development at Upper Quinam/Wokas Lakes in the Quinsam watershed. At a third site on Charters River in the Sooke River watershed, background agreements with the Capital Regional District, T Sou-ke FN and local ENGO were completed and fundraising for implementation phases in 2010 commenced. This project was co-funded by Living Rivers-Georgia Basin/Vancouver Island (2006-11), a program of the BC Living Rivers Trust Fund. |
