A review of hooking mortality rates for marine recreational coho and chinook salmon fisheries in British Columbia

Abstract

This review examines hooking mortality rates for marine recreational coho and chinook salmon fisheries in British Columbia. Hooking mortality results from non-harvest fishing and refers to the proportion of fish dying after being captured and then released (Muoneke and Childress 1994). Currently, coastwide hooking mortality rates are set at 10% for adult coho and 15% for adult chinook, independent of the gear or method of presentation used (Terry Gjernes, Fisheries and Oceans Canada, personal communication). These values come from several studies conducted in the late 1980’s and early 1990’s in Washington State (NRC 1991) and British Columbia (Gjernes 1990, unpublished), where active trolling of both artificial and natural baits was the primary method used to catch fish.

In recent years, the British Columbia tidal waters recreational fishery has declined overall but has expanded in the more remote areas, particularly with respect to both charter and lodge-based operations. Coincident with this expansion has been local preference and specialization in the types of gear being fished and the methods used for their presentation. For example, variations in “mooching” techniques (e.g. drift mooching, live mooching, motor mooching, etc) and “trolling” techniques (e.g. bucktailing, downrigger trolling, wire line trolling etc) are now widespread along the British Columbia coast. Given that hooking mortality is closely related to where hooks are located in fish (Muoneke and Childress 1994), and because different gears and methods of presentation result in salmon being hooked in different ways (NRC 1998), concern exists that the application of common hooking mortality rates to all gear types and fisheries in British Columbia may not be appropriate.

The purpose of this report is to outline current knowledge regarding hooking mortality as it relates to coho and chinook salmon captured in marine recreational fisheries in British Columbia. This review is organised into five sections. The first section summarises the scope of marine recreational fisheries within B.C. coastal waters in terms of locations fished, and fishing methods used. The second section discusses hooking mortality rate estimation and the factors known to affect hooking mortality for fish captured in sport fisheries. The third section summarises current knowledge regarding the range of hook and release mortalities for coho and chinook using different gears and methods from recent studies conducted in British Columbia, Washington, Oregon, and California. The fourth section provides an overview of recent reviews of available hooking mortality information conducted by several fisheries agencies. Finally, the fifth section (discussion and recommendations) discusses the implication of the available data and outlines priority information gaps for stock assessment consideration.