Project dates: 2010-2017

The Ocean Tracking Network (OTN) investigated stressors associated with recreational catch-and-release angling. Three popular sport fish—Atlantic salmon, Arctic char, and coho salmon—served as the models for this study. It focused on how environmental characteristics such as water temperature, and pathogen presence, and handling fish during capture and release, impact fish survival.

This study provided the first post-release data for both char (Cambridge Bay) and coho salmon (lower Fraser River). The research was conducted in collaboration with an OTN Atlantic salmon study (OTN project 4.9) to include fish angled in lower river areas soon after sea entry and those caught in the nearshore coastal environments. It is one of the first studies to link health and pathogen presence to different fisheries stressors. 

Coho salmon mortality was low and treatment-specific impacts were negligible, presumably reflecting that fish were in a mature state in the final phases of their migration. Char also had high levels of survival. Atlantic salmon had a high survival rate after release (approximately 93 per cent), although higher mortality was associated with warmer waters and post-release mortality was independent of fishing gear, fish size and fight time. Anglers who used best practices could expect released fish to survive overall, although fly fishing yielded a higher number of survivors than lure fishing. Duration of air exposure was a good predictor of fish mortality after release, however no standard for maximum air-exposure time exists and many species can tolerate different exposure times.