ODFW: Wildlife, vegetation will adapt after fire subsides
As the Eagle Creek Fire continues to burn, area residents have a lot to worry about. Homes and businesses are being threatened in the communities that have been evacuated, air quality has led to medical issues, and many are trying to find a place to stay while they wait for things to settle down.
One concern that can be abated is how the fire, which has consumed more than 30,000 acres as of Thursday, will affect local wildlife. While some animals will get caught in the blaze, experts with the Oregon Department of Fish and Wildlife (ODFW) don't expect any negative long-term impact for the fauna that call the Gorge home.
"Fire is a natural process, and wildlife evolves with it," said Michelle Dennehy, ODFW wildlife communications coordinator. "We actually may see some species flourish."
Because the blaze remains active, no one has been able to explore the region to see exactly how the natural space is being changed. But Dennehy said there is no reason to think the impact of the Eagle Creek Fire will be unique.
Young growth will thrive after the fire has burned out, which will create a good mosaic in the forests," she said.
The Columbia River Gorge is home to more than 800 species of wildflowers, 44 species of fish and 200 types of birds. There are deer, raccoons, skunks, bobcats, beavers, yellow-bellied marmots, black bears, California ground squirrels, Pacific tree frogs and garter snakes, among other species.
"There are 13 species of wildflowers that can only be found in the Gorge, and 24 endangered species of animals.
Wild animals avoid the flames in a variety of ways. Rodents will seek shelter by burrowing into the ground, taking cover in logs or hiding under rocks. Larger animals and birds will flee from the fire, using the smoke, heat and noises as signals to leave the area. Some, such as elk, will take shelter in streams or lakes.
The most at-risk animals are the young, as they may be unable to find shelter or run fast enough to escape danger.
"Some won't be able to escape, but most will make it out of harm's way," Dennehy said.
Predators will use the fire as an opportunity for easy hunting. Fleeing prey will often be caught in the open as they try to escape the flames. Woodpeckers will fly in once the fire is quelled to eat the bugs and beetles that took shelter beneath the bark.
In the immediate future, the results of the Eagle Creek Fire will be more damaging for aquatic species. There are concerns about mudslides in the Gorge as the structural integrity of the soil weakens. Debris from the landslides and ash increase the level of sediment that finds its way into streams and rivers. That can fill the pore spaces at the bottom where fish lay their eggs and can also clog and abrade fish gills while suffocating eggs and aquatic larvae.
"In the near term, there is an increased risk of high flow events, and increased sedimentation in drainages altered by fire which could alter aquatic habitats and cover spawning areas for fish," said Ken Loffink, acting deputy administrator for ODFW.
If the riparian areas located along the stream corridor have burned there could be higher water temperatures next summer, which would affect aquatic life in the affected areas.
Warmer water can be disruptive for fish in the fire zones, but they should be able to migrate up or downstream until the inferno subsides.
Eventually the fire can be a benefit for aquatic communities. Nutrients like nitrogen and phosphorus can be added to the waterway, which is needed to grow plankton and algae, which serve as food for fish.
"How fast habitat recovers after a fire can vary, but it depends on how impacted a drainage was by the fire and how 'scarred' the landscape is," Loffink said.
The vegetation is affected in different ways. Fire kills some plants, rejuvenates others, and is sometimes necessary to spur growth. It can serve as a reset button, allowing an old forest to be reborn. It leads to changes as plants, microbes, fungi and other organisms move in to the cleared land.
At this point it is hard to tell how exactly the forest will respond, but the fire should allow for the undergrowth to quickly sprout back up. Ecologists call the process succession, and through data collected through the past 200 years, the same trees that thrived before the fire ultimately return to dominate the landscape while wildlife returns.
"This fire was human caused," Loffink said, "but animals will react to it just as they would a naturally-caused fire."