By Ralph E. Mitchell
There are any number of nuisance insects that come to our attention from time to time – lovebugs as an example ! If you live near a freshwater pond or storm water retention pond, you may have had occasion to see the insect known as the freshwater aquatic midge, A.K.A, “blind mosquito” . The good news is that these insects do not bite, sting, or carry disease . However, freshwater aquatic midges can emerge in great numbers, so large in fact, that they can make themselves a real nuisance.
The freshwater aquatic midge favors bodies of water with low oxygen. These areas also tend to have elevated nutrient content which supports certain vegetative growth suitable for the larvae to feed on. The larvae are red in color and are often called bloodworms. These larvae feed on plant organic matter, eventually pupate, and then emerge in the spring and summer as adults. These resulting adults resemble small mosquito-like winged flies. During the day these adult midges hang out in shady areas under eaves , on lanai screens or around doors. They also sometimes accidentally enter homes as people come and go through doorways. The bottom-line issue is that they are a short-term, yet aggravating nuisance for some homeowners.
Management of freshwater aquatic midges can involve several strategies including efforts that help suppress their populations. First, make sure that excess nutrients are not entering the pond in the first place. Implementing best management practices such as keeping a fertilizer-free buffer around the pond and preventing grass clippings from blowing into the water should be standard business. These actions will go a long way to reduce environmental conditions favorable to midge development. Establishing six-foot buffers of appropriate plant materials around the pond can also serve to intercept and clean storm water runoff. These buffers can look both attractive and provide functional protection from excess nutrients. Another strategy may include the introduction of appropriate insect-eating fish to serve as predators. Light traps have also been suggested to divert midges from homes and reduce numbers. Additionally, there are insect growth regulators which can be applied by certified professionals. These materials effectively interfere with the development of the midge life cycle.
While freshwater aquatic midges are part of nature, certain practices can help reduce their population to numbers we can live with. For more information on all types of integrated pest management suggestions, please call our Master Gardener volunteers on the Plant Lifeline on Mondays, Wednesdays and Fridays from 1 to 4 pm at 764-4340 for gardening help and insight into their role as an Extension volunteer. Don’t forget to visit our other County Plant Clinics in the area. Please check this link for a complete list of site locations, dates and times – http://charlotte.ifas.ufl.edu/horticulture/Plant%20Clinics%20Schedule.pdf.
Gioeli, K. T., Creswell, R. L., Gellermann, J. P., Skvarch, E. A. & Koehler, P. G. (2016) Managing Pestiferous Freshwater Aquatic Midge Emergences from Storm Water Retention Ponds. The University of Florida Extension Service, IFAS.