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The Ultimate Guide to Identifying Lake Flies that Bite: A Comprehensive Overview

The Ultimate Guide to Identifying Lake Flies that Bite: A Comprehensive Overview

Lake flies, also known as non-biting midges, are a type of mosquito-like insect commonly found around lakes. Although they do not bite, their large numbers can be a nuisance to humans, especially during their annual hatch. However, some species of flies do bite and can cause discomfort and even transmit diseases to humans and animals. This article will provide a comprehensive overview of identifying lake flies that bite, including their types, symptoms, and treatments.

Understanding Lake Flies

Defining Lake Flies

Lake flies are a type of non-biting midge that are commonly found around lakes and other bodies of water. They are often mistaken for mosquitoes, but they do not bite and are not a vector for disease. Lake flies are typically small, with a body length of only a few millimeters. They are most commonly found in large numbers near the shoreline of a lake or pond.

Distinguishing Features of Lake Flies

Lake flies have a number of distinguishing features that set them apart from other insects. One of the most noticeable features is their long, slender body, which is typically gray or black in color. They also have two pairs of wings, which are clear and have a distinctive vein pattern. Unlike mosquitoes, lake flies have long antennae and do not have a proboscis for feeding.

Another distinguishing feature of lake flies is their behavior. They are most active during the early morning and late afternoon hours, and they tend to swarm in large numbers near the shoreline. They are attracted to light, so they may be found around outdoor lights or other sources of illumination.

Identifying Biting Lake Flies

Biting lake flies can be a nuisance for anyone enjoying a day by the water. Identifying these pesky insects can help individuals take preventative measures to avoid bites and discomfort. Here are some key indicators to help identify biting lake flies.

Common Biting Lake Flies

There are several species of biting lake flies, each with their own unique characteristics. The most common biting lake flies include:

  • Black Flies: Small, dark flies that are often found near fast-moving water. They have a humpbacked appearance and are known for their painful bites.
  • Midges: Small, gnat-like flies that are often found near still water. They have a slender body and long, delicate wings.
  • Mosquitoes: Small, slender flies that are often found near standing water. They have a long, thin proboscis used for biting.

Anatomical Indicators of Biting Lake Flies

Biting lake flies can be identified by their physical characteristics. Here are some key anatomical indicators to look for:

  • Mouthparts: Biting lake flies have specialized mouthparts used for piercing skin and sucking blood. These mouthparts are often visible and can help distinguish biting flies from non-biting flies.
  • Wings: Biting lake flies have wings that are often longer and more delicate than non-biting flies. In some cases, the wings may be covered in scales or hair-like structures.
  • Coloration: Biting lake flies may have unique coloration patterns that can help distinguish them from non-biting flies. For example, black flies are often dark in color and have a humpbacked appearance.

By recognizing the common species of biting lake flies and their unique physical characteristics, individuals can take measures to avoid bites and enjoy their time by the water.

Behavior of Biting Lake Flies

Biting lake flies are a common nuisance for people who live near bodies of water. They are known for their painful bites, which can cause itching and swelling. In this section, we will explore the behavior of biting lake flies, including their feeding habits and breeding patterns.

Feeding Habits

Biting lake flies are hematophagous, which means they feed on the blood of animals. They are attracted to the carbon dioxide that animals exhale, as well as other chemicals in their breath and sweat. Biting lake flies are most active during the day and tend to feed in large swarms.

When biting lake flies bite, they use their mouthparts to pierce the skin and suck blood. Their saliva contains anticoagulants, which prevents the blood from clotting and allows them to feed more easily. Biting lake flies can transmit diseases to humans and animals through their bites, so it is important to take precautions to avoid being bitten.

Breeding Patterns

Biting lake flies have a complex life cycle that includes four stages: egg, larva, pupa, and adult. The eggs are laid in water, and the larvae and pupae develop in the water before emerging as adults. Biting lake flies can breed in a variety of aquatic habitats, including lakes, ponds, and streams.

The breeding patterns of biting lake flies can vary depending on the species and environmental conditions. Some species breed year-round, while others have specific breeding seasons. Biting lake flies are more likely to breed in warm, stagnant water with high levels of organic matter.

Preventing Lake Fly Bites

Lake flies, also known as non-biting midges, can be a nuisance to people enjoying outdoor activities near lakes. Although they do not transmit vector-borne diseases, their bites can cause swelling, itchiness, and mild redness at the bite site. For some people, the fly’s saliva can trigger life-threatening allergic reactions. Here are some tips for preventing lake fly bites:

Personal Protective Measures

Wearing protective clothing can help prevent lake fly bites. Long-sleeved shirts, long pants, and socks can provide a barrier between the skin and the flies. Light-colored clothing is also recommended as flies are attracted to dark colors. Applying insect repellent to exposed skin can also help prevent bites. Repellents containing DEET, picaridin, or IR3535 are effective against biting flies.

Environmental Control Methods

Reducing the number of lake flies in the environment can also help prevent bites. Here are some methods for environmental control:

  • Light Traps: Light traps can be used to attract and capture adult flies. These traps use ultraviolet light to attract the flies and then trap them in a container.
  • Pesticide Spraying: Spraying insecticides can be effective in reducing the number of adult flies. However, this method may not be suitable for all environments and may have negative effects on non-target organisms.
  • Habitat Modification: Removing or reducing breeding sites can help reduce the number of flies in the environment. Lake flies lay their eggs in water, so reducing the amount of standing water near the lake can help reduce the number of flies.

Treatment of Lake Fly Bites

Immediate First Aid

If a person is bitten by a lake fly, it is important to clean the bite area with soap and water to prevent infection. Applying a cold compress or ice pack can help to reduce swelling and pain. Over-the-counter pain relievers such as acetaminophen or ibuprofen can also be taken to alleviate discomfort.

It is important to avoid scratching the bite, as this can lead to infection and further irritation. If the bite is particularly itchy, an over-the-counter antihistamine or anti-itch cream can be applied.

Medical Treatments

In most cases, lake fly bites do not require medical treatment. However, if the bite becomes infected or the person experiences a severe allergic reaction, medical attention may be necessary.

If an infection is suspected, a doctor may prescribe antibiotics to treat the infection and prevent it from spreading. In severe cases of allergic reaction, a person may require an injection of epinephrine to counteract the reaction.

In rare cases, a person may develop a condition called anaphylaxis, which is a severe allergic reaction that can be life-threatening. Symptoms of anaphylaxis include difficulty breathing, swelling of the face or throat, and a rapid heartbeat. If a person experiences these symptoms after being bitten by a lake fly, they should seek emergency medical attention immediately.


In conclusion, identifying lake flies that bite can be challenging, but with the right knowledge and tools, it is possible to avoid their painful bites. The first step is to understand the different types of lake flies and their behavior patterns.