... Hi just wondering I know quite a few fisherman , after catching their personal limit of 3 walleye(Oneida Lake NY) - they sit there and continue to catch many fish for fun in the winter and summer months . Somewhwere between 20 to 60 fish . What I would like to know is this stressing the fish and putting them in jeapordy pulling them up at depths over 30 ft. I never believed in this practice but these guys boost on social media - it can't be good for the fish especially in the winter . I wanted a professional answer or maybe an educated one to try to educate these guys with facts if they exist ! Thanks for your time .

I don't know about walleye specifically, but the average (mean) estimate of post-hooking mortaility across a set of studies of different fish species under catch and release is - from memory - around 15%. So while this is not an easy thing to determermine, prevailing wisdom is that appreciable mortality occurs although there are of course steps that can be taken to reduce it (barbless hooks, careful handling etc etc). there is a nice review here from a few years ago that will give you more info:

www3.carleton.ca/fecpl/pdfs/Bartholomew%20Review.pdf

It is undoubtedly the case that capture is an acute stressor for fish, and beyond the risk of immediate mortality, stress in fish typically causes sublethal effects (e.g. reduced growth, reduced reproduction, depressed immune function). Effects can be cumulative if, for instance, repeat captures lead to chronic stress. All that said, while angling related stress is unlikely to ever "benefit" a fish, it is less clear how severe the problems caused might be in abolsute terms, or relative to stressors from natural predators (i.e. herons, bigger fish etc). My unsubstantiated gut feeling is that recreational angling can a major source of stress-related problems in some circumstances, but may be trivial in others.

I agree with Alistair’s comments - a fish caught by hook and line usually constitutes a major acute stress, activating the equivalent of the mammalian sympathetic nervous system to release catecholamines and hypothalamic-pituitary-adrenal (inter-renal in fish) axis to release cortisol. How this plays out will depend on many of the same factors in mammals such as stress nature (e.g., location of hook, bait or artificial lure), intensity, duration (e.g., either acute or repeated landing time) and perhaps even adaptation to certain stressors, prior exposure to stress, genetic predisposition/stress susceptibility/species, age and perhaps even gender, and the environment (e.g., chemical composition of the water, extremes in water temperature) and can have short and long-term (e.g., reproductive) effects. In terms of catch-and-release you also have to consider the time spent out of water, and any facilitated recovery. Here is another short article on this matter - http://www.acuteangling.com/Reference/C … ality.html - walleye are briefly mentioned in a couple of tables.

Last edited by Steve Lolait (16th Jul 2015 22:38:43)