The "other species" likely winter in deeper water in lakes and rivers as the deeper water is usually most dense and therefore holds ample amounts of oxygen. I strongly believe that a lot of the fish marked by guys with electronics during the winter are those of species such as suckers,goldeye or cats that happen to slowly move by.
On L. Manitoba...a location that I often frequent I have the habit of checking out piles of non-marketable fish left on the ice by commecial fishers after lifting their nets. Very common to see drum, carp, suckers, etc...species not often caught by angling in the winter...but not nearly as many as one would expect to see if netting was done during the summer. Therefore my theory of these fish being very active and travelling around in warm water and almost "dormant" for the lack of a better words in cold water... holds some water.
FF
