If you're flyfishing for trout early in the year here's what to expect in the type of food available for trout.

Early in the year there's not much food out there. Mostly the trout are eating leeches, tiny little water bugs (pindot shrimp, daphnia and others) and some chronies. I suspect the bulk of the chronies available are bloodworms close to the bottom and not pupa. One thing to key on to catch trout early in the year is to fish the warmer areas of the lake. Those areas will have food concentrations first. Find the food and you find the trout.

Later on the primary food source is chronies. Around April 85% of what trout eat is chrones, either pupa or bloodworms.... some adults thrown in, but most of the time it's the subadult stages.

You need flats and mud in order to have chronies. They don't live in rocks, nor in marginal territory, like steep shorelines. Also, steep shorelines are usually rocks.