The biggest number of winter ticks that Peter J. Pekins ever found on a moose was about 100,000. But that moose calf was already dead, most likely the victim of anemia, which develops when that many ticks drain a moose’s blood. So it was probably a lowball estimate, because some of the ticks had already detached.

“It’s about as grody a picture as you can imagine on a dead animal,” said Dr. Pekins, a professor of natural resources and the environment at the University of New Hampshire. (A warning: The pictures below are, indeed, grody.)

Between 2014 and 2016, Dr. Pekins counted ticks on moose calves at two locations in New Hampshire and Maine. He wanted to see how the moose were faring, given that climate change has been delaying snow’s arrival in New England’s winters.