Winter ticks

About Winter ticks

Winter ticks are a one-host tick of ungulates. Large numbers of ticks can cause anemia due to blood loss, hair loss due to excessive grooming, and poor body condition due to inadequate food intake.

Commonly Affected Species:

Signs Of Disease

Winter ticks are usually not seen on animals in the larval or nymphal stages as these are relatively small. The adult males and females are the same size as typical wood ticks. The engorged adult females can be 1-2 cm in diameter. Moose, elk and deer with large numbers of winter ticks often lose significant amounts of hair, especially in late winter. Some of these animals may be lethargic and appear weak from loss of blood, hypothermia and inadequate nutrition.

Where is Disease Found?

Winter ticks are present in nearly all areas of ungulate distribution in North America except for Alaska. Winter ticks have been identified in most ungulate species in Idaho.

How Can I Protect Myself?

Winter ticks favor ungulates. The larvae and nymphs typically do not attach to humans or other animals. But the adult ticks can attach for short periods of time to humans. Removal of winter ticks can be done as for other wood ticks that are found on humans.

Samples to Collect

If there is concern about this condition, contact a conservation officer or an Idaho Department of Fish and Game Regional Office. Appropriate samples can be collected for testing if deemed necessary. Ticks can be collected and preserved in 10% alcohol for identification.

Can I Eat The Meat?

Meat from animals infested with winter ticks is suitable for human consumption.

What is IDFG doing to help manage this disease?:

Control of winter ticks depends on habitat manipulation to remove adult females after they drop from moose in late winter or early spring or removing larvae when they ascend vegetation in fall,, usually by controlled burns. Controlling moose densities to avoid buildup of tick numbers on animals in the population can minimize the numbers of ticks on individual anmals. Treatment of individual animals is possible, but difficult to do across large areas and can be expensive.