Climate Change And Dubious Science Threaten The Canada Lynx In U.S. Mountain Forests

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Image: Flickr

One of the figurative canaries in our regional coal mine for climate change has un-canary-like tufted, furry ears and big paws.  It is the Canada lynx, which inhabits the snowy mountains of the eastern North Cascades. 

Washington state considers it an endangered species.  The federal government — and the lynx’s Lower 48 relatives in northern Maine, Minnesota, Montana, Idaho, and the mountains of Colorado — considers it threatened. (All populations south of the Canadian border have been lumped together as a “distinct population segment.”) 

 “Lynx are good sentinel species for climate change,” says Dan Thornton, an assistant professor in Washington State University’s School of the Environment, the corresponding author on a recently-published lynx study. “They are like an early warning system for what’s going to happen to other climate sensitive species.”

A 2018 federal status review  pointed out that lynx habitat was going to become smaller and more fragmented; that “stressors” — including climate change — would increase; and that most crucial factors — including in Washington the tenuous connection with larger lynx populations in Canada and the growing destruction of habitat by huge wildfires — were poorly understood. 

Nevertheless, the feds want to de-list lynx in Washington and the rest of the Lower 48.  Some observers expect the de-listing proposal to come soon.  In fact, says Lauren McCain of the national environmental group Defenders of Wildlife, “we’re just expecting that proposed de-listing rule at any time.”

Huh?

The status review “doesn’t paint a rosy picture for how the lynx are doing,” says Western Environmental Law Center attorney John Mellgren.  It does make clear that no one really knows what has been happening to lynx.  “Much irresolvable uncertainty remains regarding the historical distributions and sizes of resident lynx populations in the contiguous United States,” it says.  It concedes that “a recent fire-driven decline in lynx numbers in [north central Washington] seems likely. However, we find no compelling evidence, based on verified historical records, of major range contraction or dramatic declines in the number of resident lynx in the [Lower 48 lynx population] as a whole.”

The “good” news: the reviewers expected all the lynx populations to survive five more years and even to mid-century.  By the end of the century, they figured survival odds of all but the one in northwestern Montana and northeastern Idaho will be less than 50-50.  Nevertheless, there’s no longer any need to consider them imperiled.

Right.  

Lynx in Washington and the other Lower 48 states in which they live occupy the southern fringe of their range.  They have plenty of relatives in Canada and Alaska.  But not here.  In Washington, there may be about 50 of the animals, but no one really knows.

Lynx are specialists.  They dine primarily on snowshoe hares, which are specialists, too.  Both species are adapted to environments that feature deep snow for a good deal of the year.  Both have big feet.  Hares turn seasonally white.  Change the environment, and their adaptations become competitive handicaps. 

It’s not hard to understand: Suppose you and I run a race.  It’s snowy out.  You’re wearing snowshoes.  I’m not.  Who’s gonna win?  Now suppose the snow melts.  You’re still wearing the snowshoes.  I’m still not.  Who wins now?  This is not rocket science.  Or assume you’re a hare.  You have to elude predators — all kinds of predators. ( “It’s not just lynx that eat hares; Conservation Northwest (CNW) science director Dave Werntz explains; “everybody eats the hares “)  Now assume you’re still blindingly white when the snow has melted.  Game over.

The hares like trees tall enough to keep branch tips above the winter snow, short enough to keep those branch tips within reach of a hare.  Young trees are what they need.  After a fire, you get young trees.  But you have to wait a couple of decades until they’re tall enough.  Historically, Werntz explains, there would be lots of small fires, so patches of habitat were being renewed all the time.  The hares and lynx had a kind of “conveyor” bringing new patches of young trees on-line one after another. 

Now, because of fire suppression, there are fewer fires, and they are much larger.  Places that burned in the 1990s  “are going to come on line again,” he says, “some of them in the next five years, but they’re going to all come on line at once.”  In the short term, that’s OK.  In the longer term, it will mean no constantly-renewed supply.

Climate change will leave lynx with less winter snow.  To find enough white stuff, they will have to use habitat at higher elevations.  In the North Cascades, they will be able to find it.  But going higher means having less habitat — think how much less area the snow cone of Mt. Rainier covers than the base does — and means that pockets of habitat will be farther apart.

   
Thornton and his WSU colleagues have found that lynx now occupy only 20 percent of their potential habitat in Washington. The WSU study seems to undercut the Status Review’s reassuring conclusion that no evidence suggests lynx’s historic distribution has been substantially reduced.  The authors said that their “results paint an alarming picture for lynx persistence in Washington.” Werntz says that the questions the WSU study raises about population distribution and abundance are “the sort of things the U.S. Fish and Wildlife Service (FWS) is usually pretty good at.  You’d think,” he adds, “that what came out of that paper would cause the Fish and Wildlife Service to look at [de-listing] the other way.”

Conservation Northwest executive director Mitch Friedman says that when he and his organization started working to save lynx, as far back as the presidency of George H.W. Bush, Washington had maybe 300,000 acres of lynx habitat.  Now, he says, the state has maybe a third or a fourth of that.

Friedman recalls that in 1991, he and a colleague, Mark Skatrud, wrote the first petition for a federal endangered species listing.  The feds didn’t want to do it.  CNW, Defenders of Wildlife, and other groups went to court.  That fight lasted most of the 1990s.  Lynx in the Lower 48 states finally got a threatened listing in 2000.  

Why lynx?  Friedman recalls that the Forest Service was contemplating timber sales in key lynx habitat.  Conserving that habitat seemed important.  CNW also worked to preserve lynx habitat on state land.  In 1999, after a whirlwind public fund-raising campaign (and a crucial last-minute donation by the Allen Family Foundation), it bought timber rights to 25,000 acres in the state’s Loomis forest, west of Tonasket.  The state still owns the land as a Natural Resources Conservation Area , but can’t log it.  “We used the lynx as the totem” for the Loomis campaign, Friedman says.

Lynx like dense forests with standing trees jumbled together and lots of dead wood littering the forest floor.  When a lodgepole pine forest looks like that, it’s going to burn.  Historically, though, before small fires were suppressed and big fires became the norm, lynx managed just fine. What do lynx and other critters do in the immediate aftermaths of fires? That depends on whether or not they have other places to go. They may be able to take up residence in forests that haven’t been clearcut or turned into developments. They may also use pockets of habitat that survive in “skips” — places the fire has passed over —  within the burned zone. 

Lynx by and large avoid open places, CNW’s Werntz explains, so people long assumed they’d stay away from recently-burned areas.  Now, he says, we know that’s not true. University of British Columbia scientist Carmen Vanbianchi and colleagues have pointed out the value of “skips.” Their “forest habitat models showed lynx-selected islands of forest skipped by large fires, residual vegetation, and areas where some trees survived to use newly burned areas. Lynx used burned areas as early as one year post-fire.”

It turns out that lynx like living on the edge, literally. They thrive on the boundaries between dense and open habitat, cluttered areas of dense tree growth with dead wood on the ground, and the open areas created by fire.  They can den in the dark woods, then go out and hunt in the open space next door.  Those dense areas can be the skips that fires missed.

 But skips provide immediate habitat only if people leave them alone. If government land owners order the salvage logging of standing trees in the aftermath of a fire, these pockets of habitat disappear. UBC’s Vanbianchi et. al. suggest that “increasingly severe fires or management that reduces postfire residual trees . . .  will likely jeopardize lynx and other predators. Fire management should change to ensure heterogeneity is retained . . . as fire regimes worsen with climate change.”

Once upon a time, lynx lived in the Kettle Range, east of the Okanogan Valley, largely in the Colville National Forest.  In the 1970s, that population was trapped to extinction.  Trapping has been illegal there for decades, but lynx have never returned  Now, CNW’s Friedman says, “we aspire to [getting] more lynx in the Kettles.”  Why aren’t there any now?  “It’s always been a mystery why they haven’t re-colonized” the area, Friedman says. 

Historically, when lynx populations swelled north of the border, they sent “pulses” of animals south into the Kettles.  Now, they don’t.  Friedman and his colleagues figure that  the connection with larger populations in B.C. has been broken. Lynx can’t easily walk north and south since the habitat just north of the border won’t support them.  Instead, they’ll have to go farther east, beyond the Kettle River, and then make their way west into the range.  CNW wants to help create a Cascades-to-Rockies corridor through which the animals can travel.

When it comes to international travel, even North Cascades lynx don’t get around much any more.  No one knows exactly why.  Trapping and hunting in southern British Columbia may play a part.  Whatever the reason, if lynx are isolated in their islands of U.S. habitat, they’ll eventually fall victim to inbreeding.  

Even if the government decides to de-list most lynx in the Lower 48, could it treat Washington’s population as a separate, more-imperiled sub-group?  That “certainly is an option,” attorney Mellgren says, but not one the government has been choosing with other species.

The 2000 listing, for better or worse, rested heavily on a technicality: There were no regulatory mechanisms to protect lynx.  Now, some national forest plans have been amended to mention lynx.  Is that doing any good?  No one knows, but some are skeptical.  In any case, Mellgren says,  those amendments “still allow a lot of activities that are very adverse” to lynx.  

Whatever the plans say, Mellgren argues, “you can’t just lump everything in that basket and ignore everything else” that threatens lynx.  For one, you can’t logically “ignore the effect of climate change on Canada lynx, which wasn’t even considered in 2000.”  

“We know so little about the species and what we do know is that the lynx aren’t doing well,” McCain of Defenders of Wildlife says.  Under the circumstances, “de-listing really just flies in the face of the Fish and Wildlife Service’s own science.”  Mellgren agrees. “I don’t see how they have a legitimate scientific basis for de-listing,” he says.  (In early 2018, Seattle Congresswoman Pramila Jayapal and a dozen colleagues wrote to the deputy director of the FWS stating their opposition to de-listing and asking, among other things, if the agency’s own experts thought that lynx in the Lower 48 were heading toward oblivion, how could the FWS conclude that the animals no longer needed protection.)

McCain figures “the Fish and Wildlife Service is kind of playing some games with the numbers.” In the West, she says, “the lynx are heavily dependent on the National Forests. And the Forest Service wants to really prioritize logging.”  She says, “there’s this real press to get out the cut on national forests.”  As a result, “last year was a record timber harvest year.”

Certainly Mellgren says, endangered species litigation over lynx has shut down some timber sales.  There has been other litigation, too.  He was involved in a suit before a federal district judge in Montana over the lack of a lynx recovery plan.  The judge gave the Fish and Wildlife Service two years to come up with a plan.  At the last minute, the federal government said it didn’t need a plan because it had a different kind of plan: to de-list the lynx.  How can they justify de-listing without a recovery plan, Mellgren wonders.

The plan would set benchmarks for what recovery would look like.  It’s “kind of crazy to de-list a species without a recovery plan,” Mellgren says.  “I don’t see how they have a legitimate scientific basis for de-listing.” 

Werntz agrees: “It doesn’t appear,” he says, that the de-listing effort “is being put forward by scientists.”  He says “it’s a bit rich,  I guess, to speculate that [the lynx are] doing fine without really knowing what their numbers are.” 

Inconveniently, perhaps, the Endangered Species Act requires the government to use the “best available science.”  Mellgren adds: “If they don’t do that, they will be sued.”

No doubt they will, and such litigation will take a long time.   Best case would probably be a new administration that cared about science and about species and about climate change. 

Those mountains won’t get any colder.  The lynx could use some help.

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