North Pacific Anadromous Fish Commission

Technical Report 11

Table of Contents

Understanding the Mechanisms that Regulate Coho Salmon Abundance in the Strait of Georgia, British Columbia, Canada

Authors:
Chrys-Ellen M. Neville and Richard J. Beamish

Abstract Excerpt:
There was an important commercial and recreational fishery for coho salmon in the Strait of Georgia, British Columbia, Canada in the 1970s and 1980s. The recreational fishery was one of the largest in Canada with average annual catches of 508,000 fish from 1980 to 1990 (Beamish et al. 1999). However, in the late 1980s, it was evident that abundances were declining (DFO 1990, 1992; Irvine et al. 1992). The declines continued into the 1990s with the closure of the commercial fishery in 1995 and the recreational catches diminishing to very low levels after 1994 (Beamish et al. 2008). The declines in abundance were related to the loss of freshwater habitat and to an exploitation rate that was too high (DFO 1990, 1992). However, the synchronous declines in abundance for coho salmon from the Strait of Georgia, Puget Sound and off the coasts of Washington and Oregon (Beamish et al. 2000) indicated that the major reason for the declines resulted from a declining marine survival that was related to a change in the ocean ecosystem. Importantly, the abundance declines in all these areas occurred despite additions of smolts from hatcheries that annually averaged about 100 million fish (Beamish et al. 1997), clearly showing that the declines were mainly a result of changing ocean conditions.

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DOI:
https://doi.org/10.23849/npafctr11/67.71

Citation

Neville, C.M., and R. Beamish.  2018.  Understanding the mechanisms that regulate coho salmon abundance in the Strait of Georgia, British Columbia, Canada.  N. Pac. Anadr. Fish Comm. Tech. Rep. 11: 67–71.  https://doi.org/10.23849/npafctr11/67.71