maybe they thin up in the winter??
That was one of the questions I had about flats. If they don’t eat in the winter dormant months, why would they look so healthy in the spring? Look at a bear in hibernation I thought. They are scrawny in the spring from using up the stored fat.
There are some that think flats group up in the winter to keep warm.
Bears are warm blooded and cats are cold blooded so a flat’s temp is the same temp as the water.
There was a study done in Connecticut a few years back where they acclimated flatheads to different water temps. Using fathead minnows they found flats ate very little below 50 degrees. The group that in the 40 degree water ate nothing.
Not only did they count minnows eaten, they put a scale to each fish and found their metabolism slow down so much they lost very little weight. No energy consumed, no energy used lead to very little weight loss.
This attribute of the flathead is so well documented scientifically, that MN will be having it’s first state wide closed catfish season this December 1st for the wintering months.