Salmon River Watershead Enrichment for Fish Habitat Restoration (2010)

Attached below is a report on Salmon River by Kevin Pellett from the BC Conservation Foundation for Campbell River Salmon Foundation.



On June 30, 2010, inorganic fertilizer was applied to the Salmon River (Kelsey Bay), Grilse Creek, Memekay River and the White River (July 14) to restore nutrients lost through decreased salmon production and to address footprint impacts as a result of BC Hydro diversion operations. While many species benefit from enrichment activities on the Salmon River, winter-run steelhead trout (Oncorhynchus mykiss) and coho salmon (O. kisutch) are the primary targets. A total of 3,570 kg of slow release fertilizer (Crystal Green, 5-27-0) was distributed over eight sites in the Salmon and Memekay rivers as well as Grilse Creek. Additionally, four sites in the White River/Consort Creek drainage were enriched. Partnership funding from the Campbell River Salmon Foundation, Habitat Conservation Trust Foundation and Living Rivers Georgia Basin/Vancouver Island was used to purchase, apply, and monitor nutrient applications.


Water sampling results indicate that orthophosphate and total phosphorous levels were elevated in treated reaches as compared to representative controls. Nitrogen levels were variable, but generally sufficient to support algal growth. Periphyton collector plates confirmed that chlorophyll a, used as a surrogate for algal growth, was elevated in treated reaches. However; juvenile fish growth analysis from data collected in Grilse Creek suggested that no significant difference in mean weight was achieved by fry in treated reaches. This is the first time in thirteen years that the difference in growth has not been significant. High summer flows have been suspected to reduce the effectiveness of previous treatments. In 2010, flows were nearly 50% higher than the 10 year average.