Bug Season: Biting Midges

A screened-in porch is an ideal place to relax on a summer evening. The tight, wire mesh that covers the walls allows the enjoyment of nature’s unique fragrances and wildlife sounds without the harassment of mosquitoes and other flying nocturnal pests.

However, during the early parts of summer, there is one bug that can detract from the ambiance. Biting midges are small enough to pass through traditional screens, allowing them access to any individual wanting to enjoy the evening.

The biting midges form a large group of exceedingly small true flies that are roughly the size of a sand grain, and are known to many as punkies or no-see-ums. The latter common name comes from this bug’s ability to remain unseen in low light conditions, such as on a porch after sunset, even when one of these pests has started to chew into your skin. Despite their dark color, no-see-ums are still a challenge to see clearly, even when standing against a patch of light colored skin. On a person with a dark complexion, punkies can be impossible to spot, regardless of how good the light may happen to be.

It is evident when a female biting midge has landed on your arm, leg, neck or face, as this insect is capable of producing a very noticeable bite. Her mandibles are equipped with exceedingly sharp teeth that can slice into the flesh of most creatures, and are capable of expanding to allow her to clamp onto a piece of flesh sizeable enough to encounter a surface capillary. Once the individual locates a source of blood, it begins to suck this fluid into its mouth with a straw-like appendage.

Because of their small size, biting midges produce no more than a pinch when they initially cut into a person’s skin. However, the chemicals contained in their saliva react with the surface cells of that area of the body and can inflame them and further aggravate an individual wanting an evening of total relaxation. Some people are known to experience an allergic reaction when a no-see-um bites similar to the adverse reactions an individual may experience when bitten by a black fly or mosquito.

As is the case with other biting flies, only the female requires a meal rich in proteins, as these nutrients are needed to promote the development of the eggs within her reproductive system. While some species of punkies target a specific form of wildlife, others are known to attack any creature they happen to detect when in need of a protein meal. Blood from a mammal or bird is the item that most species of no-see-ums prefer, yet there are a few types of biting midges that rely on blood from amphibians, and some even utilize body fluids from large insects.

A female may lay several batches of eggs during the few weeks of the adult stage of her life cycle. Even though she may extract blood from an individual that contains disease, the species of no-see-ums that exist in northern regions are not responsible for disease transmission. First, the amount of contaminated blood that is ingested is just too minute. Second, her stomach typically digests pathogens along with the blood; and last, the length of time that passes before she makes contact with a second host prevents disease causing microbes from remaining viable inside a no-see-um’s body.

Different species place their eggs in different settings. Some laying them in a shallow pool of water along a quiet stretch of marsh, while a few species simply deposit them in a patch of extremely moist soil that contains a rich source of nutrients. After she lays her eggs, the female, like the male, relies primarily on flower nectar for meeting her own energy needs. On occasions, sap is also extracted to satisfy an adult’s appetite.

The microscopic larvae feed on a variety of complex organic molecules around them, along with various microorganisms. Larvae that develop during the middle to end of summer are genetically programmed to enter into a dormant state in which they pass the winter. In the late spring, when conditions become favorable, they continue their development and transition into pupa. The adult emerges a short time later, and within a week, the female is looking for a meal of protein for her eggs.

A screened-in porch is a wonderful place to spend time during the evening, especially if an extended dry period beforehand has greatly reduced the population of no-see-ums.