The deep green eyes of the Canada lynx (Lynx canadensis) have the advantage in the region’s dark spruce-fir, or boreal, forest. They see without being seen. The better to go walkabout in new territories, say researchers who have tracked lynx in U.S. states such as Maine, New Hampshire and Vermont.
Cats-of-the-snow on the prowl
Lynx habitat – the boreal forest – extends across Canada and reaches down into the northernmost U.S. There lynx have it all: their main food source, snowshoe hares; the brushy woods the hares prefer; and the deep winter snows to which lynx and hares have adapted. Both species have thick cushions of hair on the soles of their large, snowshoe-like feet.
Lynx populations are in sync with those of their hare prey, according to ecologist Jeff Bowman of the Ontario Ministry of Natural Resources and Forestry. Snowshoe hare numbers peak about every 10 years, says Bowman, with lynx numbers reaching highs a year later.
South of the U.S.-Canada border, the spruce-fir forest begins to peter out, and with it, numbers of snowshoe hares and, usually, lynx. But lynx numbers in Maine are now at a relative high, according to biologist Jennifer Vashon of the Maine Department of Inland Fisheries and Wildlife. “Our last estimate, in 2006, was 750 to 1,000 adults,” she says. “We think the population has grown since then, and that lynx have expanded their range.” State biologists are conducting a new survey; they plan to have an updated count by 2018.
Maine’s lynx may be doing well enough that they’re fostering new populations in New Hampshire and Vermont – states where the snow cats haven’t been seen for decades.
Several lynx, including kittens, have been glimpsed along the edges of snowy roads in remote parts of Vermont and New Hampshire. Just as we do, lynx use thoroughfares for travel, especially in winter. People in cars – and on skis, snowshoes and snowmobiles – might find that they’re sharing highways and trails with these shadow cats.
The hunting success of an individual lynx – and the stability of a lynx population – depend not on old-growth forest, as had long been thought, but on early successional forest: woods with trees between 10 and 30 years old. Snowshoe hares hide there in young thickets or “edge rows,” the wilderness equivalent of the hedgerows where suburban rabbits hop.
Sections of forest that have been periodically harvested for timber are scattered across northern New England. Many have young trees springing up amid a hare, and therefore lynx, favorite: jumbles of downed branches atop scrubby undergrowth.
Logging can be a plus for lynx, wildlife ecologists say. It may be the equivalent of lightning-strike fires that once burned in the North Woods; such fires, researchers report, are now largely suppressed.
More than logging or fires, a tiny, native insect – the eastern spruce budworm – has radically altered forests in states like Maine. Spruce budworm killing sprees happen every 30 to 60 years. The last onslaught was in the 1970s-1980s. Millions of acres of spruce-fir forest were infected, the conifers’ needles consumed by budworm larvae until the trees died, then fell or were cut down.
But what’s bad for balsam fir and black spruce is good for lynx. As dense, old-growth coniferous forests lose trees and “revert” to early successional states with young trees and low undergrowth, snowshoe hares move in. Hot on their heels are lynx.
States where Canada lynx exist (Maine; Montana; Washington; Wyoming; and Colorado, where lynx have been reintroduced) likely have small populations. Now – thanks perhaps to spruce budworm-driven forest changes in Maine – New Hampshire and Vermont can be added to the list.
The number of lynx in northwestern New England is under debate. What isn’t a question, say biologists Chris Bernier of the Vermont Fish and Wildlife Department and Jillian Kilborn of the New Hampshire Fish and Game Department, is that the cats have returned.
Where are they coming from?
Lynx are likely crossing state lines from Maine into New Hampshire then Vermont. They might also be emigrating from areas south of the St. Lawrence, such as southern Quebec, says Bowman. He recently published results of a study of peripheral populations of Canada lynx in the Canadian Journal of Zoology. The research uncovered surprising evidence of lynx crossing the St. Lawrence River, “so some lynx could migrate to New England from north of the St. Lawrence,” Bowman says.
Adds Luke Hunter, author of the book Wild Cats of the World and president of Panthera, a wild cat conservation organization headquartered in New York, “lynx are capable of extremely long dispersal movements, particularly during hare declines.”
Whatever path these ambassadors of the northern forest took to New Hampshire and Vermont, they’ve arrived.
“For the past 30 years, lynx sightings and tracks have been intermittently documented in New Hampshire,” says Kilborn, “with little consistency until 2010 and 2011, when they became common in northern Pittsburg near the Canadian border.” During the fall of 2011, hunters spotted lynx kittens on a Pittsburg logging road, Kilborn says, “prompting us to make a concerted effort to document the distribution and abundance of lynx in the state.”
Lynx were regularly recorded during the first two years of the survey (2011 and 2012) in the towns of Pittsburg, Cambridge and Success. Then in April, 2013, lynx tracks were discovered on Kinsman Mountain in the White Mountains, the first confirmed high-elevation record in New Hampshire since the 1970s. Lynx were again observed in northern Pittsburg in the winter of 2013-14. In the winter of 2014-15, says Kilborn, “we detected a further expansion of lynx range beyond Pittsburg.”
This winter (2015-16), the scientists have come across several lynx tracks, including in the White Mountains near Zealand Mountain. “Our research confirms that there is cross-border movement by lynx along the Maine-New Hampshire line,” says Kilborn.
Adds Alexej Siren, a biologist at the University of Massachusetts Amherst who’s collaborating with the New Hampshire Fish and Game Department, “We continue to document tracks, with more lynx detected south of Pittsburg than in recent years. Our most recent sighting [on January 31st] was on state lands along a trail near prime snowshoe hare habitat. That could explain why a lynx was there.”
Next door in Vermont, the state has had at least 10 documented “citizen sightings” of lynx since 2010, according to Bernier. “Five of these were of tracks. One was of three lynx together – a presumed family group – while another appeared to be two adults together. The other sightings were all of single individuals.”
In March, 2010, a snowmobiler snapped a photo of two adult lynx, probably a breeding pair, on a trail in the Silvio O. Conte National Wildlife Refuge in northeastern Vermont. Almost every winter since, lynx have been present there. In 2013, for example, refuge scientists obtained a trail camera photo of one lynx, and detected tracks of an adult female with four kittens, says refuge biologist Rachel Cliche. That same year, says Bernier, “we confirmed the birth of at least four lynx in Vermont.”
This winter, the researchers are still on the lookout for signs of lynx.
In January, 2013, Harry McCarthy of Woodland, Maine, had his own four-lynx sighting. McCarthy was host to a group of lynx parading up his driveway. He grabbed his camcorder and was able to get a few pictures through his living room window. McCarthy posted the photos on his Facebook page. Friends saw them, and soon the snapshots went viral.
Biologists believe the lynx were likely an adult female and her three eight- to nine-month-old kittens.
The North Woods indeed has eyes.
Lynx were here: A lynx leaves a sign of its presence along a snowy hiking trail in New Hampshire’s White Mountains. (Photograph: Dylan Summers)
A related article appeared in Northern Woodlands.
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