Lake Productivity and Capacity

• Fraser Lakes Studies
• North Coast Lake Capacity

Fraser Lakes Studies

Project Leader: Ken Shortreed, Cultus Lake Laboratory

This program conducts ecosystem-level lake studies which provide information necessary for stewardship of sockeye rearing lakes in the Fraser drainage basin and for conservation, management, and restoration/enhancement of Fraser River sockeye.

Objectives of the program are to determine trophic status, limiting factors, productive capacities, and juvenile sockeye numbers, distribution, behaviour and diet in Fraser system sockeye nursery lakes. The work determines whether or not a sockeye stock is currently at or below productive capacity. If stock size is below optimal, the work determines what factors are limiting its productivity and which restoration or enhancement technique would be most effective.

Our most recent Fraser lakes publications are:

Hume, J.M.B., K.F. Morton, D. Lofthouse, D. MacKinlay, K. S. Shortreed, J. Grout, and E. Volk. 2003. Evaluation Of Restoration Efforts On The 1996 Upper Adams River sockeye salmon run. Can. Tech. Rep. Fish. Aquat. Sci. 2466: 57 pp.

Schubert, N., A. Cass, T. Cone, B. Fanos, M. Foy, J. Gable, J. Grout, J. Hume, M. Johnson, K. Morton, K. Shortreed and M. Staley. 2002. Status of Cultus Lake sockeye salmon (Oncorhynchus nerka). Pacific Scientific Advice Review Committee, PSARC Working Paper S2002-11.

Shortreed, K.S., K.F. Morton, K. Malange, and J.M.B. Hume. 2001. Factors limiting sockeye production and enhancement potential for selected B.C. nursery lakes. Can. Sci. Adv. Secretariat Res. Doc. 2001/098: 69 p.

Hume, J.M.B., K.S. Shortreed, and K.F. Morton. 1996. Juvenile sockeye rearing capacity of three lakes in the Fraser River system. Can. J. Fish. Aquat. Sci. 53: 719 733.

North and Central Coast Lake Capacity

Project Leader: Ken Shortreed, Cultus Lake Laboratory

This project is determining the productive capacity of lakes in the North and Central Coast areas, the current status of their sockeye stocks, and will identify opportunities for enhancement/restoration.

Through the use of a habitat capacity model based on primary production and limnological surveying we have estimated the carrying capacity of most of the larger sockeye rearing lakes in the Skeena River Watershed. We have also determine the current stock status of juvenile sockeye salmon in these lakes by conducting fall surveys of juvenile sockeye using hydroacoustics and mid water trawls. We are currently surveying the smaller lakes and those with more difficult access.

Much of the work to date is summarized in:

Cox-Rogers, S., J. M.B. Hume , and K.S. Shortreed. 2003. Stock status and lake-based production relationships for wild Skeena River sockeye salmon. Pacific Scientific Advice Working Paper S2003-09.