Warmer winters leading to rise of moose-killing ticks in Maine, N.H., Vermont

A moose captured for a tick count
(Native Range Inc. photo)

Researchers at the University of New Hampshire say climate change is leading to a rise in deaths among moose from ticks, Brian MacQuarrie reports for The Boston Globe. Winter ticks, which attach themselves to a single moose by the tens of thousands, are being blamed for killing about 70 percent of moose calves in Maine, New Hampshire and Vermont. "Their deadly work is being aided by warming temperatures and shorter winters that allow the parasites to survive longer, scientists believe."

"Adult females can expand to the size of a grape and engorge themselves with up to four milliliters of blood," MacQuarrie writes. Pete Pekins, chairman of the Natural Resources Department at the UNH, which is conducting a study on moose in the three states, told MacQuarrie, "The moose are being literally drained of blood. This is about as disgusting as it gets out there."

As part of the study "researchers are attaching tracking devices to the moose as part of an effort to learn how ticks are affecting them," MacQuarrie writes. "If the reduction continues, researchers said, the range of New England moose is likely to shrink northward. And for many moose that survive, the ravages of winter ticks could render them less healthy and less likely to reproduce."

New Hampshire has about 4,000 moose, down from 7,500 in the early 2000s, MacQuarrie writes. In Vermont the number has dropped from 5,000 in 2006 to 2,200 today. About 76,000 moose roamed Maine in 2012, said Maine state moose biologist Lee Kantar. While Kantar did not have current numbers, some estimates are about 60,000.