Wildfires have winners and losers in animal kingdom
By Amber Travsky
Wyoming Tribune Eagle
LARAMIE -- There are winners and losers.
That's the assessment of biologists familiar with the effects of fire on wildlife.
Dan Tyers, U.S. Forest Service grizzly bear habitat coordinator, has experience in the Gallatin National Forest north and west of Yellowstone National Park. He has been in the area since Yellowstone's historic fire season in 1988 and has observed the gradual transformation from blackened moonscape to a thriving ecosystem.
"Without a doubt, fire changes the environment," he said. "Some species find what they need with the changes and others do not.
"It also depends on fire behavior where some areas burn quickly with lower heat and other fires stay in an area and burn very hot; some take out the tree canopy and others are close to the ground."
Vicki Saab, a research biologist with the USDA Rocky Mountain Research Station in Bozeman, Mont., has conducted considerable research on the effects of fire on birds.
"There are winners and losers in the avian world," she said. "Some habitats are destroyed, and those species are the losers. Others, especially those that nest in dead snags, can be winners."
About mobility
During the fire itself, the winners and losers depend on their mobility, said Terry Creekmore. He is wildlife management coordinator with the Wyoming Game and Fish Department in Laramie.
He said wildlife that can get out of the way of a fire do so.
Creekmore's own Colorado home was surrounded by the Hewlett Gulch Fire that started in mid May. He was at his house when the flames changed direction and returned after homeowners were allowed back into the area.
"It was incredible," he said. "Even if you can't see the fire due to the smoke, you can hear and feel it.
"There's no doubt when it's time to get out of there, and the wildlife react the same way. If they can flee, they do."
Unlike the panicked exodus often depicted in the movies, the scene ahead of a fire isn't a maddened frenzy of fleeing animals. While wildlife can be seen rushing away, the evacuation is not nearly as dramatic.
Wildlife that live on the ground, such as snakes and reptiles, typically seek refuge in their burrows. Often the fire goes over them and they remain unharmed.
"Those animals that live in the trees and that might seek refuge in a cavity nest are lost," Creekmore said. "Squirrels and pine martins and other tree canopy species can't get out of the way of the fire in time."
Even if animals flee a fire, they get displaced.
"One of the first noticeable effects of a fire is finding wildlife in unexpected areas," Creekmore said. "People in Laramie may see elk or moose in town as a result of the Squirrel Creek Fire in the Snowy Range.
"The same could happen in Wheatland where they see unexpected wildlife in their backyard due to the Arapaho Fire."
Black bears appear
Reghan Cloudman is public affairs specialist with the Arapaho and Roosevelt national forests in Colorado where the Hewlett and High Park fires burned. She said there is an issue now with black bears.
"We are seeing (them) coming into housing areas as they search for food," Cloudman said.
Creekmore added that most of his neighbors reported seeing bears after the Hewlett Fire.
"The power was off due to the fire, and that meant the food in the refrigerators had time to rot, creating these big stink bombs," he said. "The bears were hungry and then they could smell the food and were raiding houses."
The time of year also affects which animals escape the flames.
Creekmore said he watched nine mule deer does wander through the blackened forest near his house n the only one still standing in the vicinity n after the Hewlett Fire.
"The does looked fine, but there were no fawns," he said. "It is likely their fawns perished since they would have been only about a week and a half old.
"Luckily the Squirrel Creek Fire in the Snowy Range was just enough later that it's possible the fawns were mobile and could flee."
Tyers said he found a number of dead moose in a valley after the Yellowstone fire.
"They hadn't burned in the fire but had died from smoke inhalation," he said. "Just like humans, they can perish not just from the flames but also due to the smoke."
Lee McDonald, fisheries biologist with Game and Fish in Laramie, said short-term impacts can result from the loss of vegetation on the stream banks and in the immediate vicinity of a creek.
"If there's a significant rainstorm after a fire, it can result in a catastrophic localized impact," he said. "Sediment, ash and debris can get washed into the creek and be very devastating."
Benefits vary
Once the fire is out and some vegetation returns, benefits can vary. The positive aspects depend on the size of the burn area and the intensity of the fire.
Creekmore said he is especially concerned with the Arapaho Fire in the Laramie Peak area.
"That fire is more than 90,000 acres," he said. "That's huge, and the impacts will likely be much more significant with so much habitat being lost all at once."
While a 10,000-acre fire, such as the Squirrel Creek Fire in the Snowy Range, is still big, by comparison it is smaller and would have less impact since wildlife can move into adjacent unburned areas.
What is unique with the Squirrel Creek Fire is that it includes Sheep Mountain.
Sheep Mountain rises above the Laramie Plains and Centennial Valley. Covering over 19,000 acres, it was designated a National Wildlife Refuge in 1924 and can be accessed on foot, horseback or via mountain bike. Motorized travel is prohibited.
The southern portion of the mountain comprises the Forbes/Sheep Mountain wildlife management area. It is closed to human activity from Jan. 1-June 30 to minimize disturbance to mule deer and elk.
Creekmore said grasses are expected to return quickly.
"That will provide good forage for the deer and elk, but they also need escape cover," he said. "It will be a long while before the tree cover returns."
In the avian world, Saab said the primary beneficiaries of all those standing dead trees are woodpeckers.
"Woodpeckers that nest in tree cavities can do quite well after a fire," she said. "Initially that may not be the case since the trees need to soften before they can use them. But three to four years after a fire the habitat can be quite good for cavity-nesting woodpeckers."
Trees weakened by fire attract bark and wood-boring beetles, which are an important food source for woodpeckers.
"Not only do they get an increase in food resources, but their nest predators, such as red squirrels, are reduced since those species need a live tree canopy," she said. "The lack of predators and increase in food supply also make the post-burn landscape particularly inviting."
Other woodpeckers, such as flickers, are slower to increase since they tend to feed on fallen logs.
"They feed on ants that are in the logs," Saab said. "Since most logs get consumed by the fire, the food source isn't there initially, but flickers increase about 10 to 12 years after a fire."
Long-term benefits
In spite of the short-term loss to wildlife and displacement, over the long term wildfire can be beneficial.
Yellowstone provides an excellent example of the impacts of fire several decades after the event.
Al Nash, Yellowstone National Park spokesman, said Yellowstone is a fire-adapted ecosystem.
"We need fire in this park as a way for nature to work," he said. "We have more of a mosaic of vegetatative ages now. Fires create meadows and edges, providing increased diversity of habitats and of wildlife."
Nash says Yellowstone looked pretty stark in some areas after the fire.
"Now we get asked if we planted all the trees people see today," he said. "We let them know that the trees came back without our help.
"While we still have some areas that have not bounced back as well, two decades after the fire the majority of the burn areas look great."
Cloudman agrees that fires can be beneficial and wildlife can adapt.
"It's the magnitude of the fires, such as the 87,284-acre High Park Fire, that changes the dynamic," she said. "We had all the dead beetle-killed trees but even the living trees were exceptionally dry. That meant even the living trees burned."
On the positive side, the High Park Fire was a "dirty" burn. That means there is a mosaic within the burn area of patches that didn't burn as hot, and some areas even remained somewhat unscathed.
"Since the fire was often wind-driven, it didn't stick around for long," Cloudman said. "There are variations in the degree of burning and that is good news for wildlife.
"It is problematic for firefighters since there's always the possibility that the fire will reignite in those unburned areas."
One wildlife species that has remained below pre-1988 fire levels in Yellowstone is the moose.
Moose rely on tree cover to cool down in the summer months. When fire removes that cover, the moose move out and, as has occurred in Yellowstone, they are slow to come back until the cover returns.
Moose are an example of being a winner in the sense that they're mobile enough to escape a fire, but they can be a loser if the needed habitat is so slow to return.
The long-term effect on fisheries can be beneficial too n if more woody debris gets lodged in the stream.
"That creates more fish habitat," McDonald said. "As long as the riparian vegetation returns fairly quickly, fire impacts can be positive in the long term"
It's too soon to know the extent of wildlife losses, both short and long term, due to the fires this season. As wildlife, fisheries and habitat biologists fan out to assess the impacts, the winners and losers will become more apparent.
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