Effect of hook type on mortality, trauma, and capture efficiency of wild stream trout caught by angling with spinners

This study assessed short-term (48-h) hooking mortality, eye damage, jaw injury, and capture efficiency of three species of wild stream trout caught on size-1 Mepps spinners having barbed or barbless treble or single hooks. The mortality of rainbow trout Oncorhynchus mykiss, brown trout Salmo trutta, and brook trout Salvelinus fontinalis was low (<4%). Hook types did not differ significantly in causing mortality or severe eye damage of rainbow trout or brown trout. Severe eye damage was evident on about 10% of the trout landed (range = 2% to 13%, depending on species). Jaw injuries were found on about 6% of the catch. Barbed hooks hooked and held more trout than barbless hooks and treble hooks hooked and held more trout than single hooks. Barbless single hooks were quicker to remove than the other hook types, but the difference was insufficient to reduce mortality. Our results do not indicate a biological advantage with the use of single- or barbless-hook spinners when caught wild stream trout will be released.