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Originally Posted by dothepuff

Not trying to cause anything just looking for info and thoughts on the matter.



If it's not best to fish in deep water how do people go about catching fish that live in deeper water...lake trout come to mind as one or accidental catch's of other species. Trying to find more info on it being a leading cause of fish mortality. I would think that if there is so many fish being brought up from deep waters that there would be quite a few dead fish always floating around in the summer and in the spring after the ice lifts...

Generally dead Fish, just like drown human bodies, sink until decay bring them to the surface. Here most fish are consumed, unless they are vey large, before they resurface. Catch and release fatalities are also much lower while ice fishing or fishing cold waters, this is well known. The reasons are probably multi factorial but I would think it not unrealistic that barotrauma would be one of the factors. As you know the volume of a gas in a bag is not only proportional with external pressure but also Temperature. While ice fishing the fish would be going from a max of 4 degrees a the bottom and getting COLDER to zero as you brought him up. A very small degree change and it vis a vis the temperature should cause a small decrease. The summer would be completely opposite. Ie the fish would be coming from quite a cold place at depth to a much warmer temperature at the surface (about a 16 degree change) and hence have an expansion effect on the swim bladder.

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I agree that it is well documented...but with people making claims about all this bad stuff that happens to the fish coming up from deep water there isn't much documented on it and no one is sharing any literature or links....just to go out and say it's bad and wrong.....well...I would think if it is such a tragic matter there would be literature published in the regulations to educate the anglers??

Page 23 of the guide "Fish for walleye and perch in relatively shallow water.
For more information, obtain a copy of the pamphlet “Handle and
Release Fish with Care” from your nearest Fish and Wildlife Office." They have put info like this into the guide for a number of years now.

For the best info go down to your local University Library and use their data bases there and you will find that there is actually quite a bit of info on this.




Agree 100%, I also think that if this descending device can save a few fish it is worth having one in the tackle box. Wondering what the long term damage is as the longevity, would imaging it would be more sever for certain species of fish and maybe size?



Not sure what to say on this...I've fished some of the bigger lakes in AB, Sask and Man and we were well over 30' catching everything...never seen any fish come up showing any sign of the bends and even watched big lake trout chase the hooks up to the surface from over 80' fow...some never took the hook and swam back down to the depths they were at.Yes Lake trout have evolved to hunt like this not sure that it is valid for walleye and perch though.

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