Midge flies, also called blind mosquitoes, are ubiquitous throughout Florida. They belong to a very large and diverse family of aquatic insects with their immature stages occurring in the water. They resemble mosquitoes in size and shape but thankfully they do not bite, sting, suck blood or carry disease.
Midge flies can be a problem in Florida all year, but swarms tend to be worse in the dry hot spring and early fall when water tables are at their lowest. The larvae thrive in shallow lakes or shallow areas around the shore and their numbers can grow exponentially in water with high levels of nutrients, low oxygen, and bottom muck. The larvae live on the lake bottom making them more difficult to control and to detect imminent adult swarming.
A swarm of midge flies by your Florida lake, pond or waterway is an annoyance, and it may seem like a good idea to be rid of them all. However, they are a food source for other aquatic insects such as dragon fly nymphs, several varieties of fish, birds and some bats. The goal is to not totally eliminate them, but to bring them into proper balance with the ecosystem. A balanced lake ecosystem is a healthy lake ecosystem.