It is one of the earliest lake fishing hatches of the season. Many people may recognize these insects as the long slender black midge with two little white wings folded back symmetrically . The males have two fuzzy antennae. In total the fly measures about 7mm long. Some species of midge are non-biting but there are also the biting midge flies, disgusting!
Many fly hatches on a lake are along the lake shoal. The area from the lakeshore to the shallow water is called an ecotone. The bottom layer of water is the benthic layer. Some species of midge larvae thrive in this layer of water, often tolerant of low dissolved oxygen, while other midge species prefer faster, colder water. Yet they can also be found in oxygen-rich trout lakes, living together where there is an abundance of nutrients. Macroinvertebrates (animals without a backbone which can be seen with the naked eye) often dwell in this lower layer and eventually become the visible winged insects such as the midge. The Chironomids start as little red worms then eventually migrate as a pupa to the surface. At their pupa stage, they appear to have shiny bubbles inside their shuck, which the insects will shed off their body. Once they leave the shuck the Chironomids will have wings to dry off by hovering over the surface of the water. This sudden dance above the water is always fascinating.
Recently out on an inland lake I witnessed the Chironomid hatch beginning. I measured the water temperature with my thermometer and it read 52 degrees Fahrenheit. All around me there was evidence of midge fly pupas and shucks. I reached into the water to pick up a specimen. One had a black sticky egg sac attached to the abdomen, a female. These eggs then drop into the water to begin the next generation of midge flies. None of these mid-April flies were biting me, but beware of the mosquitos accompanying them when the sun sets!
To most individuals who travel by boat these flies are nothing but a nuisance. However, to the fly fisherman these are the beginning of an exciting event in the lake. Trout love them and birds love trout. If you look for the diving birds, like the loons, you might spot fish. Observe the wind direction as the drift may carry in insects to hungry fish accompanied by hungry birds. If you find the trout, they will be gulping up flies in surface boils or leaping out of the air! Try fishing with a TDC pattern (which resembles the pupa stage), a small lake mayfly, or with an adult midge pattern (which has the matching tone of black or brown color). Fish might bite a hook resembling a midge fly. The fisherman will see a surfacing trout gulp many flies before ending up on the fishing hook. With so many morsels for trout to choose from, fishing this hatch is more of a challenge! Good luck!