Every fall, New Hampshire’s moose pick up an enemy they cannot shake. Winter ticks latch on by the tens of thousands, and over the cold months they drink their fill of blood, weakening the state’s largest land animal and frequently killing its calves. Some adult moose carry upward of 50,000 ticks at a time. As Henry Jones, the moose project leader for New Hampshire Fish and Game, put it, “Essentially, they get the life sucked out of them.”
Now a team of New Hampshire scientists wants to know whether the answer to this slow-motion crisis has been hiding in the way the state’s forests are cut. A new study, approved to move ahead by Gov. Kelly Ayotte and the Executive Council on Wednesday, June 3, as reported by the New Hampshire Bulletin, will test a deceptively simple hypothesis: that the pattern of logging across the landscape may be quietly steering moose into the same tick-infested ground year after year. If the researchers are right, a change in forestry practice could become one of the first real tools to slow a decline that has worried biologists, hunters, and the tourism industry for two decades.
Why the moose are in trouble
The health and numbers of New Hampshire’s moose have been sliding for roughly 20 years, and winter ticks are the single biggest reason. Research by the University of New Hampshire and Fish and Game has identified the parasite as the driving force behind the regional decline of moose across the Northeast. The ticks are native to New Hampshire and target moose, deer, and other hoofed animals. They climb aboard their hosts in the fall, feed through the winter, and drop off again in spring to lay their eggs.
What changed is the math. In recent decades the number of ticks parasitizing moose has boomed, helped along by a warming climate. Longer stretches of autumn without snow on the ground give the questing ticks more time to find a host before winter sets in. “The way climate change is affecting moose is through parasites,” Jones said.
Climate is only part of the story, though. UNH professor Remington Moll, one of the study’s leads, points to a population boom that peaked in the Northeast in the early 2000s. The sheer abundance of moose during those years gave ticks an enormous supply of hosts, and tick numbers climbed to the high levels that persist today. In other words, the herd’s past success helped build the parasite load now dragging it down.
The toll is severe. Blood loss weakens adult cows and reduces how many calves they can produce. For young calves, heavy infestation through a first winter brings anemia and nutrient deficiency that is often fatal. Winter ticks are the leading cause of death for moose calves under one year old, according to the Maine Department of Inland Fisheries and Wildlife.
What has and has not worked
Biologists have not been short on ideas, but each has run into a wall. One option is to raise hunting quotas to thin the herd, on the theory that fewer moose means fewer hosts and, eventually, fewer ticks. Fish and Game has already increased target moose harvests in northern New Hampshire with that logic in mind. But as Moll notes, the research behind this approach is thin, and other states are only now testing it, so no one yet knows whether it will actually break the tick cycle.
A second idea is chemical. Tick-killing pesticides could in theory be applied to the landscape or directly to the animals. The problem is practicality and principle. “If you can get a moose and put pesticide on the moose, it helps,” Moll said. “But it’s just logistically very hard. And conceptually, it’s kind of a non-starter, because you don’t want to be putting pesticide everywhere in the forest.” Blanketing New Hampshire’s woods in tick poison is neither feasible nor something most residents would tolerate.
That leaves a third, far less explored avenue: managing the habitat itself.
The logging hypothesis
Moose are drawn to young forest, where tender new growth provides abundant food. Recently logged tracts fit the bill perfectly. Because timber harvesting is usually done one large block at a time, the researchers began to wonder whether moose return to those same productive patches every fall and spring, feeding in the same spots and, in the process, dropping and picking up ticks again and again in the same ground.
The timing matters. Winter ticks do not travel far during the summer after they fall off their hosts. So if moose keep coming back to a small number of rich feeding sites, they may effectively be handing the next generation of ticks an easy target. Break that routine, the thinking goes, and you might break the cycle.
To find out, Moll, Jones, and their colleagues will fit moose with GPS collars and collect tick samples across moose habitat. They want to learn whether the animals really do return to the same locations year after year, and which kinds of forest hold the heaviest tick concentrations. If the hypothesis holds up, it could point toward a new conservation tool: more dispersed logging that scatters young forest across the landscape, encouraging moose to vary their movements and lowering the odds that any one animal walks into a tick hot spot.
Initial work begins this summer, though the team will not start collaring moose until more than a year from now. The project carries an estimated price tag of about $1.2 million, with three-quarters funded by a federal grant from the U.S. Fish and Wildlife Service and the remaining 25 percent coming through the University of New Hampshire.
Why it matters for New Hampshire
The moose is more than a charismatic backdrop for a postcard. Fish and Game Executive Director Stephanie Simek and Business Division Chief Kathy LaBonte told the governor and council that protecting the animals serves the state’s tourism economy, its hunting heritage, and its ecological balance, as well as the moose themselves. The state’s broader work on land and wildlife, from forest management amid rising drought and wildfire risk to long-running research on how a warmer, drier climate is reshaping New Hampshire’s water and woods, all feeds into the same question this study asks: how do you keep an iconic landscape intact as the climate shifts beneath it?
For now, the researchers are careful not to oversell. The forest angle, Moll said, simply has not been examined before. “We don’t know if there’s going to be a strong connection or not, but it’s important to pursue that question because it’s never really been answered,” he said. “We love moose, and we want to figure out what’s going on with them so that we can adjust management and conservation efforts to keep them around.”
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