Lower Fraser fishwheels and biotelemetry for improved in-season estimates


Year 2008
Proponent LGL Limited
Project type Fisheries
FSWP funding source Living Rivers
Grant amount $340,437.00
Total project value $754,073.00
ID number 08 SIFM LR 43

Location: Mission, BC

Project Summary

Three important strategies within the FSWP work plan are: engagement of First Nations, development of more sustainable fisheries and improved information for fisheries management.  This project addresses each of these strategies and is part of a multi-year initiative to address concerns related to the in-season abundance estimates, in-river survival, migration behaviour and species composition for Fraser salmon. 

Major components of this initiative include: 1) the 2007-08 feasibility studies for using fishwheels as a live capture platform to provide salmon for tagging and species composition estimates on the lower Fraser River; 2) estimating sockeye abundance passing Qualark using DIDSON hydroacoustic equipment; and 3) radio-telemetry to assess migration rates, in-river survival and fishery impact on sockeye.

Data from past studies indicate that species composition can vary substantially between near-shore and off-shore (mid-channel) waters in the lower Fraser River.  The Whonnock gillnet test fishery likely provides a good sample of the species composition for off-shore waters but is not suitable for assessing near-shore waters.  The opposite is true for the Crescent Island fishwheels. In addition, the 2008 data indicate that the DIDSON hydroacoustic gear, drift gillnet test fishing and radio-telemetry arrays were effective methods for assessing sockeye passage at the Qualark site.  The combination of the data from these three programs (Qualark, Whonnock and Crescent Is.) with the Mission hydroacoustic site can be used to derive reliable specific estimates of salmon escapement past Mission.

Sockeye radio-telemetry studies have provided estimates of in-river survival as well as the location of any enroute losses between Mission and the spawning areas.  Results from the proposed 2009 sockeye telemetry combined with estimates for other years, will be used to detect trends in enroute losses that could result from changes in environmental conditions (e.g. water temperature and flow) and/or changes in fisheries (e.g. timing, intensity and gear). The 2009 telemetry data will be important for evaluating and building confidence in a combined Mission-Qualark assessment system by providing direct measures of the migration rates between Mission and Qualark, and helping to explain any differences observed between the escapement estimates derived from spawning ground surveys and those derived from the Mission and Qualark hydroacoustic projects. 

Another high priority issue for Fraser salmon is related to the run-timing, abundance and fishery impacts on spring-run Chinook salmon.  In-river harvest rates estimated for several Spring 42 chinook stocks have been consistently higher that those for all other Fraser Chinook stocks and spawning numbers for these populations have declined substantially in recent years (English et al. 2007a; 2007b).  Consequently, we have proposed to apply 100-150 radio-tags to spring-run Chinook captured along the Fraser River between Hope and Yale in order to assess migration rates, in-river survival and spawning distribution for these stocks.  The stock origin for each radio-tagged Chinook will be determined from the analysis of DNA samples and tracking data for each fish.



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