Mark the middle of September on your calendar and make plans to hit the closest trout lake for an astounding feeding frenzy. Every September around the middle of the month backswimmers and their close cousins the water boatmen go on a fall migration. These water bugs are beetle like critters that fly from smaller water bodies to lakes and rivers so they can overwinter. They migrate in such numbers that when they start dropping into a lake, it may appear like it’s raining.
With a profuse number of bugs coming into a lake, every trout that swims will clue in and be looking up on the hunt to cash in on this bounty. Backswimmers, however, don’t make themselves an easy target for hungry trout and these bugs use massive paddle like legs to kick them down to the bottom in a hurry. For the trout that means they’ve got to catch their meals fast or miss out. This sets up a scenario where trout are super aggressive and crush anything that remotely resembles a backswimmer. The solution to catch a lot of trout becomes simple, imitate a backswimmer, catch fish.
For us anglers, there are a multitude of backswimmer flies that will do the job extremely well, but I stick with a small bead head prince nymph. It plunks in like the real thing and then I retrieve it with a non-stop series of quick jerks. This effectively imitates the backswimmer’s action and the hits come fast and often. For the two week window when the backswimmer migration is in full swing the action will be fast and furious so I say, pick up your rod, be it a fly rod or a spinning rod and enjoy.