Several factors cause fish to move in mid-winter
Bitterly cold temperatures dominated the weather scene in the Bemidji area this past week in what was, hopefully, the coldest week of the winter.
The extended forecast predicts the cold temperatures will last at least through the early part of next week which will likely keep the bite slow again this weekend for most anglers.
For several reasons, fishing is typically slow during the coldest part of the winter. Metabolism is at the low point for the year so fish don't have to eat as often to maintain their weight.
Fishing pressure eventually moves fish, too. The fish begin to thin out in areas that have been pounded by anglers early in the winter. Anglers harvest some of the fish and many others move out of the area because of the noise on the ice.
Oxygen levels in the deepest portions of the lakes begin to drop because of fish respiration and decaying algae that has settled to the bottom of the basin.
The shallows may also become depleted of oxygen because of the large amounts of decaying vegetation. The lakes are locked in by the cold so there is very little new oxygen being added to the water.
By mid-winter many of the fish have begun to leave both the weed-choked shallows and the stagnant deep water and begin to gravitate towards the mid-range depths where oxygen levels are higher.
Anglers begin to lose contact with the fish as they change locations and patterns. To stay on the fish anglers have to keep moving around the lake to find new patterns and fresh schools.
Anglers have severely limited mobility this winter because of the deep snow and slush on the lakes. Most anglers with stationary houses are either making short moves or staying in their current locations and taking what they can get for fish.
There is usually a dramatic up-tick in the activity levels of all species of fish at some point in February. Eventually the weather breaks and the lakes begin an alternating pattern of melting and refreezing.
The melting snow and ice on the warmer days periodically flushes some fresh water into the lakes, which helps move more fish back into the shallows.
Fish also begin to stage for spawning during February, especially in larger lakes. Early spawning species like walleyes and northern pike often have long distances to travel to reach their preferred spawning sites. Consequently, they begin their migrations in mid to late-winter as the weather conditions start to improve.
Most anglers in the Bemidji area are still fishing the larger lakes where there are plowed road. Winnibigoshish has about a dozen resorts that plow roads so anglers can use whatever resort is plowing roads closest to their favorite part of the lake.
The action on Upper Red Lake has been slow but steady with anglers catching a few walleyes during the day and a little better flurry in the mornings and evenings.
The crappie population in Upper Red Lake has dropped significantly since its peak, with the majority of the crappies remaining still from the one huge age class of fish from 1995.
Crappies seldom get older than 12 to 15 years so most of the remaining crappies in URL have outlived their life expectancy or they are from a smaller age class of fish. Crappies need near perfect conditions to put in a successful spawn.
Clear water lakes like Bemidji, Cass, Leech and Winnibigoshish still have the best action for walleyes in the mornings and evenings. Most anglers are finding walleyes in 24 to 32 feet of water on the edges of structure.
Perch fishing has been slower in deep water for most anglers, with large schools of perch difficult to find. There are also schools of perch on the shallower mid-lake flats that are covered with chara or rocks, but the perch are usually on the move and difficult to stay on because of the poor ice conditions.
Crappies have been feeding in 25 to 40 feet of water in most situations, with many of the crappies suspending 5 to 10 feet off the bottom.
Paul A. Nelson runs the Bemidji Area Lakes Guide Service. He can be e-mailed at email@example.com.