Abstracts

Climate impact and adaptation responses of salmon and water managers on the Somass River to the 2002 fall drought in British Columbia

Kim Hyatt¹, Josie Cleland, and Margot Stockwell
¹Fisheries and Oceans Canada
hyattk@pac.dfo-mpo.gc.ca

Salmon populations on the southern end of their range are considered to be highly vulnerable to climate warming impacts. Southern British Columbia experienced a severe fall drought in 2002. On Vancouver Island's Somass River, limited water supplies and high temperatures created multiple threats to fish and fisheries associated with natural and cultured populations of salmon. Water supplies and withdrawals are regulated at several locations in the Somass system to meet the needs of fish, industry (hydro, pulp mill, aquaculture facilities) and urban populations. Review of impact and adaptation responses of fish, fisheries and water managers to the drought indicated the following. Fish experienced delayed migration, delayed spawning, shifts in habitat selection, and decreased survival. Managers responded through emergency retrieval of daily information on resource status and an order of magnitude increase in consultations with stakeholders. The 2002 drought confirmed the vulnerability of major assets in both natural and "built" environments on the Somass and other BC rivers to climate change. Future extremes may dictate negotiation of multiple-asset "tradeoffs" involving significant economic losses. Development of impact models and adaptation options including "standing order responses" to extreme climate events could reduce the magnitude of future water resource conflicts, fisheries management crises and costly litigation in Canada. However, the creation of integrated assessment models and overarching processes to increase our adaptive scope to climate change outcomes in fisheries will require much greater levels of interdisciplinary and inter-sectoral co-operation than current institutional arrangements produce.

2005-04-05