The effectiveness of stream habitat rehabilitation was evaluated in year two of a five-year program in the treated (logged and rehabilitated) watershed, the Keogh River, compared to the
neighbouring and untreated (logged, no rehabilitation) watershed, the Waukwaas River. Anadromous salmonid density and growth were compared in untreated and treated reaches of the
Keogh River, which contained a variety of stream habitat structures as well as fertilized and unfertilized sections. Treatments were added annually to previously untreated reaches, starting
upstream and working downstream with various placements of structures, and starting downstream and working upstream with addition of slow-release fertilizer, incrementally from 1997 to 1999. Significant increases were found in steelhead parr and fry abundance and coho fry abundance overall at the watershed level and in reaches treated with rehabilitation structures, compared to untreated controls both within and between watersheds, despite low levels of adult escapement. Detailed analyses of structure usage by species indicated variation from year to year; climatic factors (stream discharge) may have influenced annual variations in species and age-class distributions. A diversity of structural types appears to provide an optimum strategy for habitat rehabilitation, rather than singular types. Analysis of salmonid growth in-stream, continued to indicate that significantly larger salmonids were found in fertilized sections. Results indicate that habitat rehabilitation for juvenile salmonids in streams may partly counteract recent dramatic and persistent declines in survival observed in freshwater and marine life stages...
McCubbing, D.J.F., Ward, B.R.. 1998. Stream Rehabilitation in British Columbia's Watershed Restoration Program: Juvenile Salmonid Response in the Keogh and Waukwass Rivers 1998. Ministry of Environment. Watershed Restoration Project Report. WRPR12