Lake Trout Food Sources
This article will focus on food sources of lakes. While many of the same patterns that are used frequently in river fly fishing will also apply in lake fishing, there are some different areas of concentration for lakes.
First of all, let me state that this is intended as a general source of information. There is nothing like first hand information for the lake you are intending to fish, whether it is by observation, collection of samples, or talking with locals, direct information about your location is always the best. However, there are some generalities and some fundamental information that can be applied to lakes in general.
I keep several fly boxes dedicated to just lakes, they are filled with midges, mosquitoes, scuds, damsel and dragons, leeches, buggers, crayfish, and terrestrials.
Midges are also called Chironomid, and they are of primary importance to lake fishers. They are small, worm-like in shape, and are in abundance in the majority of lakes that will hold trout. Chironomid are a reliable food source for lake trout, and can emerge every month of the year that the lake is ice free. Reliable patterns include, chironomid pupa, chironomid bomber, snow cone, pure midge, rs-2 emerger, wd-40, and for low visibility situations, the disco midge can't be beat. And for dry fly fishing try the Griffith Gnat as well as small parachute patterns like the Sprout Midge Emerger work really well.
Most anglers will fish a chironomid under a small indicator, or on a floating line with a very, very slow retrieve. These insects don't move much, or very quickly, so it is a painstakingly slow way to fish if the fish are not gorging themselves in your general area.
Virtually every alpine lake fly fisher, knows the both the curse and blessing of the mosquito. They can both foil and save the fly fishing trip. Showing up unprepared in your fly box is bad enough, but showing up without skin protection will quickly end your trip. Mosquitoes are a hearty species indeed, hibernating all winter to show up at the earliest possible time when warming begins. They drop their resilient eggs in shallows and are valuable to fish both as larva and as adults. They can vary greatly in size so be prepared with everything form 12-16 in dries, and use chironomids for the larva.
Scuds are without a doubt my favorite food source for lake trout. They have high caloric content for trout, so they are readily gulped. They are a great indicator of healthy trout populations. In fact, I know of no lake that doesn't have scuds that does hold trout. I am sure they exist but they aren't the rule. Scuds are simply freshwater shrimps, they are omnivores feeding on smaller creatures and vegetation alike. They can be many different colors depending on their diet, but are most commonly gray, tan and olive. Like midges, they are constantly available and are probably more desired than midges due to their high caloric content.
Dragonflies and Damselflies
Crayfish and LeechesLeeches, crayfish, and forage fish are all food sources for trout. They can exist in varying availability, depending on the lake and the season, but trout will not ignore them when present. They have the added bonus of attracting larger than average trout. We were recently able to read some lake surveys done by the USFS for the Gifford Pinchot National Forest. The lakes with the big trout all had healthy crayfish populations. Lakes with small trout did not have many, if any, crayfish...
Terrestrials are anything born on land, of most importance to lake anglers are ants, beetles and sometimes hoppers. Ant falls in particular produce great fishing. But all terrestrial fishing greatly improves with the aid of a high unpredictable wind. Concentrate on banks full of foliage where terrestrials might be lying.
Mayflies are not to be ignored just because your lake fishing. Again get to know your waters, but callibaetis, Tricos, and Hexagenia are all common in lakes, and their specific hatches can result in some of the hottest fishing of the year. Callibaeits tend to hatch mid day, after rains, and during cloudy days as well. They hatch over long periods of time (often all summer). The action can be crazy! They can be tan, olive, brown, or gray. Hexagenia are huge and hatch in huge numbers over a short time. One local lake here has a huge hatch that lasts about 3 days, usually right before the 4th of July.
Like river fly fishing, lake fly fishing requires patience and dedication to excel at it. Different, but equally as rewarding, lake fly fishing cam offer solitude that can be hard it find at popular river destinations.