Creature Feature – Winter & Fish Activity

What do fish do under the ice all winter?  Is the phrase “go to sleep with the fishes” based on fact?  Fish have different adaptations and strategies that help them survive winter.  They are cold blooded, so their body temperature is the same as their surrounding environment.  When the water gets cold, fish do, too. They experience a reduction in their metabolism, which triggers a decrease in respiration, digestion and activity.  Fish are classified as cold water, cool water and warm water species.  Warm water fish, like largemouth and smallmouth bass and panfish, will seek out the warmest water possible.  In winter, this is usually the lake bottom. To conserve energy, warm water species also avoid places with a strong current.  They lay low and enter a state of lethargy. Cool water fish, such as northern pike, walleye, crappie and perch, remain somewhat active; but they also experience a reduction in metabolic processes as water temperatures drop, seeking out the warmest places to hunker down.  Both warm and cool water species generally lose weight over the winter. Cold water fish include whitefish, burbot, and varieties of trout and salmon.  These hardy fish stay robust throughout winter, actively hunting throughout the water column and gaining fat.  This can translate to late season success for ice anglers.

Article & Photo by Margie Manthey