It is unclear how big a toll wildfires have taken on the Mount Graham red squirrel, but lingering drought and an emergency cutting project likely pose the greater threat to the endangered animal, wildlife officials say.
There were 284 squirrels on the mountain this spring, up 10 from six months earlier, according to a survey released last week. It is too soon to tell how the squirrels have fared as the “Nuttall” and “Gibson” fires have burned across the southeastern Arizona mountain. But biologists plan to visit the area as soon as firefighters allow them in.
Meanwhile, controversy is building over the U.S. Forest Service’s emergency decision to cut trees in a 200-foot ring around the Mount Graham International Observatory. Robin Silver, a longtime critic of the telescope project and a founder of the Center for Biological Diversity, said the action “sterilized” an area that has been a critical habitat for the squirrel.
“We’re talking about rendering the area useless to squirrels for centuries,” Silver said.
Forest officials acknowledge that it will take a generation or two for the spruce and fir trees that used to populate the forest nearest the telescopes to grow back. But they say the cutting was needed to protect the observatory as the flames neared.
And, Dean McAlister, fire-management officer for the Coronado National Forest, said the emergency project was not a clear-cut.
“There are still trees standing,” McAlister said.
Fire crews removed dead, standing trees in a 50-foot area beyond a 150-foot protective buffer that was there. The crews cut from 1,000 to 1,500 trees, according to news reports, but McAlister said he could not estimate how many trees were felled.
Tom Skinner, wildlife program manager for the Coronado National Forest, said he and his staff surveyed the area ringing the observatory before the emergency cutting began. They did not find any active middens, the nests where the red squirrel stashes its food.
“Because of drought and bark beetle, those middens were inactive,” he said.
In fact, the ongoing drought and the bark-beetle infestation pose bigger threats to the squirrel, biologists say.
Wildlife officials estimate that most the spruce-fir forest above the 10,000-foot level on the mountain is dead.
That area, the favored habitat of the squirrel, has seen an 80 percent drop in squirrel population because of the stressed forest conditions, said John Koprowski, an associate professor of wildlife and fisheries science at the University of Arizona who has been tracking the Mount Graham squirrel population.
“When you have small populations, there are all kinds of concerns with the possibility of a catastrophe,” he said.
For example, the squirrels could flee in different directions, establishing separate communities that may not be big enough to survive.
But biologists don’t even know how the squirrels respond to the threat of a fast-moving wildfire, he said. There are no studies, even though Arizona has witnessed some catastrophic fires in recent years.
For example, Koprowski said it’s unclear if the squirrels would hole up in their ground burrows, flee or try to protect their young.
Once the fire is out, Koprowski, along with researchers from the Arizona Game and Fish Department and the U.S. Fish and Wildlife Service, will survey the forest for an animal count. There are radio collars on 45 red squirrels.
Meanwhile, wildlife officials at Arizona’s other major fire, the “Willow” fire near Payson, say at least six “activity centers” for the endangered Mexican spotted owl were burned. As with the squirrel, it’s impossible to estimate how this will affect the species until a post-fire survey can be done, said Shawla Hedwall, a biologist with the U.S. Fish and Wildlife Service.
But Hedwall said the loss of the patches of forest will further limit the owls’ options, since much of the surrounding area is piñon-juniper forest, an area not suited to the owls.
“Those birds don’t really have a lot of opportunities for moving to other areas,” she said.