What Happens to Fish in the Winter: The water is cold so the fish don’t need food andf they can go all winter withoit eating. Many fish hybernate, like ctafish, the school up and just sit there. You might still find a few active fish but 99% are hibernating. Carp, Gar, and most other fish also hybernate. You can see the giant flathead from bridges sitting in shallow water, just sitting there and they won;t move all winter.
Walleye and Sauger like to do a Fall run but not all fish run to dams, some stay down river in deep water or even go into deep lakes. You can catch them in cold weather but most are not feeding because they just don’t need food, they already fed up in the fall before the water temp got to 33*. Reaction baits work well because the fish hit the lure by reaction without thinking. The Walleye and Sager go deeper and deeper and can even be found down in 50′ of water. On average they will sit in 20-35′. If you put a jig in front of their face they may eat it, but probably won’t. If you swim it by them you might get a reaction bite, but the big feed is over.
Bass, Bluegill, Perch and Crappie feed good at first ice but then also slow down and most won’t touch anything. They like to swim around and cruise without eating much. Some just sit without moving much, in schools, especially in lakes.