During the cold months of the year, lake fishing is largely ignored. In large part this is due to most lakes freezing clean over until early spring. Yet there are years, like this one, when the weather is relatively mild and the lakes are free of ice with happy trout gorging themselves on a variety of aquatic insect life. The fish haven’t been pressured or harassed in months and now freely and non-selectively prowl the waters for their next meal. This presents a great opportunity to wail on big trout outside of prime season but we need to change our tactics to succeed.
It is important to understand the dynamics of a lake in the winter. With the cold air permeating the surface thermocline the warmer water is pushed to the deeper portions of the lake. Surface temps. can read 2 to 3 degrees colder than 10 to 15 ft. down in the water. This means the majority of the food and fish will typically be found in the warm deep parts of the lake as opposed the shallows where they are found in the Spring and early Summer. So forget about fishing the shallow ends of the lake unless fish are consistently rising.
Mornings are going to be the slowest part of the day because the water is at its coldest. The best plan of attack is to string up a full sinking line with a medium to large leech pattern. It is important to make a nice long cast and then wait for the line to sink fairly deep before retrieving the leech back. Most full sinking lines have a specific sink rate to gauge the depth of the line over a period of time. Count the time the line sinks and vary it until you find the depth where the fish are feeding. Also vary the strip from a fast retrieve to a slow retrieve until you find the pace the fly needs to move. Typically in the colder water, a slower retrieve will prove to be more effective.
As the day progresses and midges begin to start hatching, it is usually a good time to start chironomid fishing. Typically in the spring and early summer a 3 to 4 foot spread between the fly and the indicator is all that is needed but in the winter the spread needs to be larger. There is definitely a thermocline that the fish will be gorging themselves on chironomids, so adjusting the depth is important until fish are caught on a consistent basis. Sometimes this means lengthening the leader out to 12 or 15 feet to get the fly down to the feeders. Make sure that the majority of the leader below the indicator is 5x tippet and tie the chironomid on a loop knot to get the most natural presentation.
From mid-afternoon until 4 p.m. be on the lookout for the water boatmen hatch. The adults lay the eggs by diving into the water and swimming down to the bottom of the lake. These egg layers are an easy target for feeding trout and the fish key into them quickly. Fish a sub-surface water boatmen on a floating line in water 4 to 6 feet deep. It is important to vary the retrieve until you find the speed the fish are after. Water boatmen are erratic swimmers so short strips, 2 to 3 at a time with a pause in between will be the most effective retrieve.
Be adaptable and willing to change flies and lines to adjust to the varying conditions with an emphasis on fishing deeper than usual and success will be had. Remember to be aware of insects and change according to what is occurring at the moment. If all else fails start experimenting with different patterns and presentations.