We had quite a wind last night and the fish are reaping its benefits. Dissolved oxygen levels in ice-covered lakes get lower over time because there is limited mixing of air and water. On smaller lakes and ponds this depletion of oxygen occasionally causes fish kills, when the level of dissolved oxygen gets so low that it won’t support the fish. A big wind like we had last night whips up the water in good-sized waves, and mixes in a lot of oxygen. Since the ice has only been out for two days, the dissolved oxygen level had been pretty low, but last night likely brought it way up. And with it, the activity level of the fish will similarly increase.