American Dog Tick

Dermacentor variabilis

ticktexas.org

American Dog Tick Female

ticktexas.org

American Dog Tick Male

The American Dog Tick is the largest of the eastern wood ticks, and the one you are most likely to see. Ticks are arachnids and, like their spider cousins, have eight legs.

The American Dog Tick is reddish-brown with white or yellow markings. The male tick is about 1/8 inch long, and the female is slightly larger. She will get much bigger (about 1/2 inch), though, after she drinks her fill of blood.

Ticks are parasites, and they must find a mammal host for blood. They use their claws to grab onto a host and then dig under the skin with their mouthparts. Their mouth lets out a chemical, which is an anesthesia, to keep the host from knowing it's there. The tick can then bury its head in the host's flesh and drink as much blood as it wants.

Copyright, Tom Murray

American Dog Ticks are known as "three-host ticks," because they have three different host animals in their lifetime.

First, the larva hatches from its egg. Larvae only have six legs, like an insect.

The larva will stay on the ground or climb up a plant or shrub to wait for a host to pass by.

Monmouth County Mosquito Commission

American Dog Tick Larva

Monmouth County Mosquito Commission

American Dog Tick Nymph

The larva will detect a trail or place where mammals often go by smell and bodyheat. It waits with its front claws outstretched to grab the first small mammal that comes by. This is usually a mouse, vole, squirrel, chipmunk, mole, shrew, muskrat, or rabbit. The picture above and on the left is a American Dog Tick larva. The larva drinks its fill of blood (about four days) and drops off its host.

Next the larva molts (sheds its skin) and become an eight-legged nymph. The nymph will look for a new host. It may be another small mammal, or something bigger like a opossum or raccoon.

Copyright, Joyce Gross

Copyright,Tony DiTerlizzi

Jim Kalisch

Once the nymph has grabbed a new host, it will again drink more blood, this time for about six days. It will again drop from its host and molt. This time it may take weeks before it molts and becomes an adult tick.

The male and female ticks will again look for a host, their third one. It will most likely be a larger mammal, such as a raccoon, opossum, fox, skunk, woodchuck, deer, dog, or human. This time the male will not feed. The female will feed on the host, and the male will mate with her while she feeds. After mating, the male will die and the female will drop off the host to lay eggs on the ground. She will lay over 4,000 eggs and the cycle will begin again. If a tick can't find a host in any of its stages, it can survive up to two years.

Jim Kalisch

Because American Dog Ticks have flat bodies, and a hard, protective "shield," they are not easily injured, and they have few predators.

Media

Description
Type
Credit
American Dog Tick Feeding
Video
Unknown
American Dog Tick's Head Under a Microscope
Link to Image
Uglybug.org

Download Quicktime if you are unable to play video

Relationships in Nature:

PREY/FOOD
PREDATORS
SHELTER
OTHER

Meadow Vole

Red-backed Salamander

Poison Ivy

Meadow Vole H

Least Shrew

Wild Turkey

Virginia Creeper

Least Shrew H

Eastern Gray Squirrel

American Toad

Common Milkweed

Eastern Gray Squirrel H

Woodchuck

Five-lined Skink

Goldenrod

Woodchuck H

Eastern Cottontail

Eastern Newt

Witch Hazel

Eastern Cottontail H

Eastern Chipmunk

Garden Centipede

Sassafras

Eastern Chipmunk H

Red Fox

Harvestman

Greenbrier

Red Fox H

White-footed Mouse

Highbush Blueberry

White-footed Mouse H

Raccoon

Bracken Fern

Raccoon H

White-tailed Deer

Red Clover

White-tailed Deer H

Human

Smooth Crabgrass

Human H

Virginia Opossum

Pokeweed

Virginia Opossum H

Muskrat

Smooth Sumac

Muskrat H

Striped Skunk

Queen Anne's Lace

Striped Skunk H

Common Dandelion

Common Reed

Common Elderberry

Spotted Joe-pye Weed

Black-eyed Susan

Relationship to Humans:

Few people can find a good use for ticks. They can be dangerous parasites for you and yor pets since they carry diseases such as Rocky Mountain Spotted Fever and Lyme Disease. They are being collected and studied in order to find cures for these diseases.

SCIENTIFIC CLASSIFICATION

KINGDOM
Animal
PHYLUM
Arthropod
CLASS
Arachnid
ORDER
Acarina
FAMILY
Ixodidae
GENUS
Dermacentor
SPECIES
Dermacentor variabilis

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