Barotrauma

[jschmitt]

Last weekend my boys and I went to Sodus to catch a few perch for the pond.  We had a big cooler that we planned to keep the fish in until we got back to the truck.  I ran an aerator with a little battery and freshened up the water as needed.   We fished 22 ft.  Every fish we caught had barotrauma.  We tried to reel them in slowly and it made no difference. I even let one sit at 10 ft for a minute just to see if it helped. It didn't.  We placed the fish in the cooler and they all (100%) swam belly up. I figured it was just a matter of time and they would right themselves.  After 3 hrs. they were still doing this so we stopped keeping fish because I wasn't sure they would make it.  Im telling you it was shocking.  Not a single one was swimming properly under the ice when I released them into my pond. I wet the entire area to see clearly through the ice.  Im sure every fish I put back did the same.  Thoughts.

My questions are:

1) Is there an effective way to vent a perch?  I have done it with grouper in Florida per requirement.

2) What is really happening when we put these fish back.  I never see them after they go down the hole.  Are they all floating belly up along the underside of the ice? 
If so, think of what that is doing to the population structure.

3) If fishing deep are we just killing everything we catch?

Also:  Before someone goes after me for moving perch.  The pond I put them in is landlocked (no outlet) and more than a half mile from other waterways so disease transmission is not an issue.  I didn't realize that was a no no honestly, as most people I know got their fish for their ponds from other bodies of water.  I looked it up before posting this, but felt that what I saw was important enough to mention even if I made a mistake in transferring fish to new waters.
 

[jperch]

I think there are two issues here.  A perch brought from 22 feet directly to the surface will have its' air bladder expanded by about 60% by volume compared to what it was at the bottom.  That is why a perch has a difficult time going back down, it's like they are wearing a life preserver.  Then there is the matter of how much damage is done to the fish by the stretching of any air filled cavities, the "barotrauma".  We have all seen the bulging eyes of perch that were harvested from 40 feet and deeper.  One thing I used to do on Conesus was to pinch the barbs down on my hooks and when I hooked a perch that was clearly not a keeper just let the line go slack until it wiggled itself loose.  For your pond, not advocating that you do it, but fish caught in 8 or 10 feet of water would probably not have that problem.

[jschmitt]

Great idea. Thank you.