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8 Common Biting Insects in Wisconsin (Pictures)

Wisconsin is a beautiful state, full of forests, rivers, and wetlands. It’s no wonder that so many people want to spend their summers hiking, camping, and fishing in this natural paradise. However, one downside to all this outdoor activity is the biting insects. While some of these insects are harmless, others can carry diseases that can make you very sick. Here are some of Wisconsin’s most common biting insects and what you need to know about them.

8 Biting Insects in Wisconsin

1. Inland Floodwater Mosquito

Inland floodwater mosquito
Inland Floodwater Mosquito | image by Katja Schulz via Flickr | CC BY 2.0

Scientific Name: Aedes vexans

The Inland Floodwater Mosquito is one of the most common mosquitoes in Wisconsin. This mosquito breeds in standing water, so it’s often found near lakes, ponds, and marshes. The Inland Floodwater mosquito can carry diseases like West Nile virus, encephalitis, and dog heartworm.

The main source of food for this mosquito is nectar from plants, but the female mosquito will also bite humans and animals to get the protein she needs to lay eggs. Their eggs can remain dormant for years, waiting for the next flood to hatch them. Inland Floodwater Mosquitoes are most active at dawn and dusk but can also bite during the day.

2. Bedbugs


Scientific Name: Cimex lectularius

Bedbugs are small, flat insects that feed on the blood of humans and animals. A grown bedbug can measure up to 1/5 of an inch long.

They’re most active at night, and they can bite you without you even knowing it. Bedbugs are not known to carry any diseases, but their bites can be very itchy and uncomfortable.

Bedbugs have been known to ingest up to seven times their own weight in blood. They can live for up to 400 days without feeding, and female bedbugs can lay up to 500 eggs in their lifetime.

Bedbugs are most often found in mattresses, bed frames, and headboards, but they can also live in furniture, carpets, and baseboards.

3. Horse Flies

Horse fly
Horse Flies | image by Frank Vassen via Flickr | CC BY 2.0

Scientific Name: Tabanidae

Horse flies are large, predatory insects that feed on the blood of mammals, including humans. They’re usually dark-colored, with patterned wings, and can grow up to 1.25 inches long. Horse flies are most active during the day, and their bites can be very painful.

They have a top speed of up to 90 miles per hour and have an adult lifespan of 30 to 60 days. Female horse flies can lay up to 1000 eggs in their lifetime. Horse flies are most often found near livestock, but they can also be found near other areas where mammals are present.

4. Black Flies

Black fly
Black Fly | image by Jean and Fred Hort via Flickr | CC BY 2.0

Scientific Name: Simuliidae

Black flies are small, dark-colored flies that feed on the blood of mammals, including humans. They usually measure between 0.08 and 0.23 of an inch long. Their bites can be very painful, something that’s made worse by the fact that they often swarm their victims.

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They have a lifespan of two to three weeks, and female black flies can lay up to 800 eggs in their lifetime. They usually lay their eggs in running water, so they’re often found near rivers, streams, and wetlands. Black flies are most active during the day.

5. American Dog Tick

American dog tick on wood
American dog tick male | image by K-State Research and Extension via Flickr | CC BY 2.0

Scientific Name: Dermacentor variabilis

This tick feeds on the blood of mammals, including humans. They are known as a three-host tick, meaning they will feed on three different hosts during their lifetime. It’s usually dark brown or reddish-brown in color, and an adult female measures 1/2 inch long when fully engorged with blood.

This tick can carry diseases like Rocky Mountain spotted fever and tularemia. And while they may carry the bacteria that causes Lyme disease, they are not able to transmit it to humans.

The American Dog Tick is most often found in wooded areas, but it can also be found in grassy or brushy areas. They are most active during the spring and summer months.

6. Deer Tick (black-legged tick)

Black-legged deer tick on plant
Black-legged deer tick on plant | Image by Erik Karits from Pixabay

Scientific Name: Ixodes scapularis

The deer tick is a small, dark-colored tick that feeds on the blood of mammals, including humans. While females have a dark red abdomen, males are either entirely dark or have a dark brown. Adults can grow up to 0.12 of an inch long.

The deer tick is known to carry several diseases, including Lyme disease, anaplasmosis, and babesiosis. They’re most active during the spring and fall, but they can be active year-round if the temperature is warm enough.

7. Fleas

Ground nesting bird flea
Ground nesting bird flea | image by Olha Schedrina via Wikimedia Commons | CC BY-SA 4.0

Scientific Name: Siphonaptera

Fleas are small, brown insects that live off the blood of animals and humans. They’re most often found on dogs and cats, but they can also hitch a ride on rodents, rabbits, and even people. While fleas can jump up to 13 inches high, they prefer not to and will usually only jump onto an animal or person if they’re already close by.

Fleas can carry diseases like typhus and bubonic plague, and they can also transmit tapeworms to animals. A female flea can lay up to 50 eggs per day, and the eggs can hatch in as little as two days. The entire life cycle of a flea, from egg to adult, can take as little as two weeks.

8. Body Lice

body lice
Body Lice | image by Gilles San Martin via Flickr | CC BY-SA 2.0

Scientific Name: Pediculus humanus corporis

Body lice are small, wingless insects that live in the seams of clothing and feed on human blood. Adult body lice can grow to 0.14 of an inch long. They’re usually pale in color but can darken to brown or black after feeding.

Body lice are most often found in crowded, unsanitary conditions. They can spread diseases like typhus and relapsing fever. Female body lice can lay up to 300 eggs in their lifetime. The eggs, which are called nits, hatch in about a week.

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