Need some advice on a weird situation, yesterday after the last of ice thawed I noticed catfish floating on the surface. I guess I lost 10 cats. Upon further investigation we found dead tad poles about 3/4 inch long and lots of smaller blue gill and bass dead in the leaves on bottom. I am asking myself why would there be tad poles this time of year and such small fish. Almost like they had a hatch in the fall and froze in. I am boggled. Any insight?

How deep is the pond? Likely low oxygen killed them. The combination of ice cover, and anaerobic decomposition from decaying plant matter used up the O2. Tadpoles will winter over under the ice before they make the transformation in the spring. Once again, low O2 got the tadpoles also.

Yep, Yaz probably has it right.

Things you can do:
1. Make the pond deeper.
2. Add an aerator or source of incoming water.
3. Keep your weeds controlled during the summer so you don't have a bunch that will die off under the ice.

its a little over a 1/4 acre and 17 foot deep in the middle , basically a damned up ravine. I have heard of Aerators, Any options other than running electricity to it? That would be a heck of a project

I've heard just cutting holes in the ice, and splashing in the hole will put air under the ice. But I don't know that would be enough. Might be a good question for THROBAK.

electricity to the pond or an air line to it

1/4 Acre isn't very big, but 17' is nice depth to hold a few fish. Guessing it's just overpopulated for the carrying capacity, so when oxygen levels got low during freeze up it killed some off, hopefully not all of them.

The big cats make it worse when they are all gathered up in the deepest hole and stir up the silt. I'd get the cats out of there and go with hybrid bluegills.

My buddy just runs an extension cord and puts his portable air compressor in the hole with no attachment on it. He ties the hose to a jug and lets it go for a day or so then shuts it down. He does that a couple times every winter and it works really well.

The 17' depth makes is easier to properly aerate. Instead of running electricity to the pond, run an air line using inexpensive poly (black) water line (1/2"). The line is much cheaper than wire and you don't have to put it underground.