WINTER Tick (aka MOOSE Tick)

winter / moose tick

  • The Winter or Moose tick, Dermacentor albipictus, is similar in size and appearance to the American dog tick.

  • The larvae are brown, about the size of a pinhead.

  • Adult winter ticks look like slightly elongated versions of the American dog tick.

Identifying Factors

Habitat & Season

The winter tick isn’t active in the summer and it completes its entire development on one host. It is often found on moose, deer, or horses during the fall, winter or spring. Eggs of this species hatch in the spring, but the larvae remain bunched together, inactive, all summer long. They don’t become active until cold weather returns in the fall. As with other ticks, they wait on leaf litter or low vegetation for a host to brush by. After attaching to a suitable host, this species remains on the animal, feeding and molting until it has fully grown. Then it drops off, and eggs are laid on the ground in the spring.

Winter Tick is more abundant farther north in New Hampshire.



Winter tick doesn’t commonly bite people, and does not transmit agents that cause disease. Winter ticks kill moose because there are so many of them they are weakening the moose by extreme loss of blood causing anemia. Sometimes moose are found in winter with large patches of bare skin, carrying thousands of winter ticks. Such heavy infestations sometimes kill the moose. Recent research in New Hampshire demonstrates that winter ticks are limiting the moose population, and mortality of calves is especially high.

Learn more about tick-borne diseases on our Diseases Page →