die offs?

[brokenline]

how can you tell if a lake has died off? the small walleyes and perch are still around on the camera but there is a wierd film that develops in the hole. would the fish float up the hole?

[HawkEyeman]

I have no idea what that film might be. But, the classical winter die off happens when all the oxygen is consumed from the water prior to ice out. If you see fish swimming around on your camera the lake isn't dead. At least not completely.

Not sure out to check for it unless you have some device to measure the oxygen level in the water. I just assume that if we have some major ice that smaller lakes/ponds and shallow lakes/ponds are at risk.