12-25-2010, 10:21 PM
[cool][#0000ff]I was going to stay out of this, since the thread went back to being about fishing Chesterfield and not about fish handling. But, after it surfaced over here I started a thread on it on the Utah Board. We had some good positive discussion...about the different factors involved...and how much they REALLY affect the survivability of released trout.[/#0000ff]
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[#0000ff]I have been researching for almost two years, trying to find published results from any biological studies that have been done on mortality rates of trout C&R while ice fishing...especially related to exposure to ice and snow. I haven't found ANYTHING. [/#0000ff]
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[#0000ff]Here is my synopsis of the input and opinions expressed on the Utah Board:[/#0000ff]
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[cool][#0000ff]Good input and discussion...AND it has remained civil and professional. Great![/#0000ff]
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[#0000ff]Almost as expected there have been no references to actual published reports from fisheries biologists on the EXACT effects of ice and snow upon trout...for C & R. Lots of theories and opinions...as expected also. Let's list a few.[/#0000ff]
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[#0000ff]1. We all agree that all trout will have a better chance of survival upon release if handled carefully...or not at all. I still cannot find any websites that cover proper handling techniques on ice but I did find one that had some good overall tips and suggestions for general trout handling. [url "http://trophytroutguide.com/articles/cpr.htm"]TROUT HANDLING[/url][/#0000ff]
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[#0000ff]2. Fish slime removal. Dry towels, gloves and bare hands are far more likely to remove protective slime from trout skin than ice or snow. The slime serves two purposes...protection against disease and skin parasites...and lubrication. It covers the rough scales and reduces friction in the water (and when dragged across ice or snow). However, the slime producing glands in the skin usually replace lost slime fairly quickly and unless rough handling injures the fish they can recover soon without much threat of skin ailments...especially in cold water with less potential for harmful organisms in the water.[/#0000ff]
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[#0000ff]3. Harm from flopping on the ice. It could happen, if the fish are dropped from any height at all. But not likely to result from the fish's flopping around. Besides, there is usually a protective and cushioning layer of snow on the ice most of the winter. Rare to be just hard ice.[/#0000ff]
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[#0000ff]4. Skin freezing from contact with ice/snow. Again, the protective layer of slime provides some protection against "flash freezing" if the fish is only briefly in contact with ice or snow while being unhooked or photographed. The potential for harmful freezing is much greater if the fish is hoisted into subzero air with the wind blowing. That supercools the entire fishes' bodies...especially delicate eyes and gill tissue. Human skin freezes quickly (frostbite) if not protected against harsh freezing condtions. So will fish parts.[/#0000ff]
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[#0000ff]5. Abrasive action of ice and snow. This would be more of a factor if the fish were forcibly held down against the ice or snow. But their body weight alone is not enough to create a problem. It is quite the opposite. The surface of the ice and snow is uneven...like the surface of a golf ball...and the slimy skin of the fish slides easily across the rough surface without damage. Just don't stomp on the fish to quiet it down.[/#0000ff]
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[#0000ff]In short, there are two primary sources of harm to fish exposed to ice and snow. First is the handling with dry hands or gloves...or other clothing...to remove slime. Second is the potential for tissue damage due to prolonged exposure to extreme cold surfaces or air. After that it is the same for any trout caught in any other manner. Proper handling, lifting, control, etc. The bigger the fish the more likely it is to suffer damage from improper lifting or control techniques.[/#0000ff]
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[#0000ff]I am still searching for documentation on the variable mortality rates for trout handled in different ways on snow and ice. My thinking is that it would be very difficult to set up controlled experiments to monitor the outcomes over an extended period of time...on a large enough sampling of fish...to make any accurate determinations. [/#0000ff]
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[#0000ff]In the meantime, I will continue to conduct my own personal research...both for catch and release and keep and consume (release in the grease). I have definite mortality figures for the latter.[/#0000ff]
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[#0000ff][/#0000ff]
[#0000ff]I have been researching for almost two years, trying to find published results from any biological studies that have been done on mortality rates of trout C&R while ice fishing...especially related to exposure to ice and snow. I haven't found ANYTHING. [/#0000ff]
[#0000ff][/#0000ff]
[#0000ff]Here is my synopsis of the input and opinions expressed on the Utah Board:[/#0000ff]
[#0000ff][/#0000ff]
[cool][#0000ff]Good input and discussion...AND it has remained civil and professional. Great![/#0000ff]
[#0000ff][/#0000ff]
[#0000ff]Almost as expected there have been no references to actual published reports from fisheries biologists on the EXACT effects of ice and snow upon trout...for C & R. Lots of theories and opinions...as expected also. Let's list a few.[/#0000ff]
[#0000ff][/#0000ff]
[#0000ff]1. We all agree that all trout will have a better chance of survival upon release if handled carefully...or not at all. I still cannot find any websites that cover proper handling techniques on ice but I did find one that had some good overall tips and suggestions for general trout handling. [url "http://trophytroutguide.com/articles/cpr.htm"]TROUT HANDLING[/url][/#0000ff]
[#0000ff][/#0000ff]
[#0000ff]2. Fish slime removal. Dry towels, gloves and bare hands are far more likely to remove protective slime from trout skin than ice or snow. The slime serves two purposes...protection against disease and skin parasites...and lubrication. It covers the rough scales and reduces friction in the water (and when dragged across ice or snow). However, the slime producing glands in the skin usually replace lost slime fairly quickly and unless rough handling injures the fish they can recover soon without much threat of skin ailments...especially in cold water with less potential for harmful organisms in the water.[/#0000ff]
[#0000ff][/#0000ff]
[#0000ff]3. Harm from flopping on the ice. It could happen, if the fish are dropped from any height at all. But not likely to result from the fish's flopping around. Besides, there is usually a protective and cushioning layer of snow on the ice most of the winter. Rare to be just hard ice.[/#0000ff]
[#0000ff][/#0000ff]
[#0000ff]4. Skin freezing from contact with ice/snow. Again, the protective layer of slime provides some protection against "flash freezing" if the fish is only briefly in contact with ice or snow while being unhooked or photographed. The potential for harmful freezing is much greater if the fish is hoisted into subzero air with the wind blowing. That supercools the entire fishes' bodies...especially delicate eyes and gill tissue. Human skin freezes quickly (frostbite) if not protected against harsh freezing condtions. So will fish parts.[/#0000ff]
[#0000ff][/#0000ff]
[#0000ff]5. Abrasive action of ice and snow. This would be more of a factor if the fish were forcibly held down against the ice or snow. But their body weight alone is not enough to create a problem. It is quite the opposite. The surface of the ice and snow is uneven...like the surface of a golf ball...and the slimy skin of the fish slides easily across the rough surface without damage. Just don't stomp on the fish to quiet it down.[/#0000ff]
[#0000ff][/#0000ff]
[#0000ff]In short, there are two primary sources of harm to fish exposed to ice and snow. First is the handling with dry hands or gloves...or other clothing...to remove slime. Second is the potential for tissue damage due to prolonged exposure to extreme cold surfaces or air. After that it is the same for any trout caught in any other manner. Proper handling, lifting, control, etc. The bigger the fish the more likely it is to suffer damage from improper lifting or control techniques.[/#0000ff]
[#0000ff][/#0000ff]
[#0000ff]I am still searching for documentation on the variable mortality rates for trout handled in different ways on snow and ice. My thinking is that it would be very difficult to set up controlled experiments to monitor the outcomes over an extended period of time...on a large enough sampling of fish...to make any accurate determinations. [/#0000ff]
[#0000ff][/#0000ff]
[#0000ff]In the meantime, I will continue to conduct my own personal research...both for catch and release and keep and consume (release in the grease). I have definite mortality figures for the latter.[/#0000ff]
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