Highways bring death to animal habitats
Seattle Times science reporter
Even at 70 mph, Dennis Grapp could see the scarlet evidence of a deer killed on the highway.
Then he glimpsed a small, brown spot in the tall grass of the Interstate 90 median. It was a newborn fawn, "all wobbly legs and shaking."
Grapp, 55, of Woodinville once ignored an injured deer on a road in Idaho. Years later, he still regretted it. And while he hunts deer and elk, he thought, "This is just a little baby."
At the next exit, he pulled off and headed back to try to save another deer from one of the biggest threats to wildlife: the road.
This is high season for roadkill, the butt of bad jokes but a growing concern for wildlife and transportation managers sensitive to human sprawl and jeopardized animals.
With newly born birds and mammals finding their way in the world, and adults often traveling farther to feed and breed, Northwest roadways increasingly are littered with dead and dying opossums, raccoons, squirrels, deer and the occasional elk.
It's a danger to people, too. Deer-auto collisions cause an average of $2,000 in damage per accident and nationwide kill between 130 and 210 people a year. In some rural areas, residents say there are only two kinds of people: those who have hit a deer and those who will.
The ever-expanding web of highways and roads concern biologists in other ways, too. They reduce, fragment and often degrade habitat.
Animals must either risk their lives to maintain their territory or hunker down in smaller spaces, straining resources, limiting movement for mating and constraining young animals looking for new territory.
"Roadkill is the least of our problems when it comes to impacts on our wildlife," said Trisha White, transportation associate for Defenders of Wildlife and head of its Habitat and Highways campaign to reduce the impact of surface transportation on wild creatures.
In some ways, the problem is beyond solving with so many roads already built and mounting human needs for homes and services — all in what once was wildlife habitat.
Scientists and road builders are studying options, and in Washington state they are undertaking several projects aimed at easing pressure points such as where Grapp last week found the fawn.
As it happens, scientists have studied that very spot, estimating that between 26 and 35 dead deer and elk had been found in a mile-long stretch just west of Cle Elum, Kittitas County, over an eight-year period.
Accurate roadkill figures are hard to come by. One rough estimate is that a million vertebrates die every day on the nation's 4 million miles of roadway, and research suggests that number is growing.
In Washington state, Department of Transportation (DOT) workers each year pick up between 2,450 and 3,000 dead deer and elk. Labor and equipment costs in the last biennium were about $1 million, with some roadkill salvaged and given to Indian tribes.
And the deer spotted by maintenance workers are only a percentage of those actually killed, said Sandy Jacobson, a Bonners Ferry, Idaho-based Forest Service wildlife biologist on special detail on transportation and wildlife interactions.
While workers will document animals found on a roadway, injured animals frequently wander away to die out of view or succumb to predators.
Locally, opossums lead the pack when it comes to getting killed, said Kris Meyer, field supervisor for King County Animal Control. They're slow and have poor eyesight, relying instead on smell to get around. When confronted with something they don't recognize, they tend to open their mouth and glare.
"That may have worked before vehicles — it doesn't work for them now," said Jennifer Convy, rehabilitation manager for the Progressive Animal Welfare Society in Lynnwood.
But it's the habitat laced and broken up by roads that causes even more harm, say biologists. Reduced habitats can only support smaller animal populations.
The local population can then become extinct, "winking out" as it fails to rebound from disease, famine, fire, catastrophic weather or roadkill rates that exceed birth rates.
A small population also lacks the genetic diversity needed to prevent problems of inbreeding.
Roadways are particularly tough on habitat for large carnivores like bears, wolves and lynx, said Bill Ruediger, the U.S. Forest Service's ecology-program leader for highways. They tend to have low population sizes, low reproduction rates and a large range most likely to be affected by highways.
Gray wolves, which have drifted on their own into Montana from Canada, stopped migrating south when they hit I-90, Ruediger said.
In Washington, I-90 is a concern of the state DOT as it prepares to improve the freeway east of Snoqualmie Pass, a major corridor for wildlife movement up and down the Cascade range.
The department is considering an animal overpass near Easton Hill, Kittitas County, site of frequent collisions, and longer bridges that will leave more room for animal corridors alongside streams.
"There are all kinds of associated ecological benefits that you can have just by having a bigger bridge," said Peter Singleton, an ecologist for the U.S. Forest Service's Pacific Northwest Research Station in Wenatchee, who has studied the area extensively.
Outside of Sequim, DOT and the state Department of Fish and Wildlife two years ago installed half a dozen flashing "Elk X-ing" signs that are activated when radio-collared Roosevelt elk come within a quarter-mile of a section of Highway 101. No data is available on how effective the signs have been.
The DOT has also identified more than 500 road culverts that block salmon passage because they are too high or steep. The agency has replaced 69 of the culverts with some larger ones giving animals a way to cross under roads.
Last week, the DOT started putting up signs in the Methow Valley urging caution. The signs tally the number of deer killed so far this year and the estimated dollar value of vehicle damage from collisions.
"There was a holdup for a couple of days," said Jeff Adamson, communications manager for the DOT's north-central region. "They didn't have enough zeroes."
So far this year, 58 deer have been hit, causing an estimated $145,000 in damage. Based on a Mule Deer Foundation survey of Okanogan County body shops, the DOT figures each deer causes about $2,500 in damage.
One of the more industrious efforts to help wildlife near roads involved 22 underpasses, two 164-foot-wide overpasses and 8-foot-high fencing on 28 miles of the Trans-Canada Highway in Banff National Park. Deer and elk roadkill dropped by 96 percent.
But wildlife overpasses can cost millions of dollars.
Dennis Grapp used a more low-tech method.
After turning around to retrieve the orphaned fawn on I-90, he found her lying in the median about 40 feet from her mother's smashed carcass. He tied off the umbilical cord — she had apparently been born on impact — and wrapped her in an old flannel shirt. At home, Grapp and his wife nursed her overnight on goat's milk from a Playtex baby bottle.
The next day they took her to the Progressive Animal Welfare Society, which unceremoniously named her Number 1513. At first she was weak, lethargic, dehydrated and suffering from low blood sugar, but after a few days she was standing and attempting the head butts that infant deer make when they nurse.
Soon she'll be released into a pen with several other fawns. They are fed by bottles on a rack to prevent their getting used to humans. In late fall, she will be released to the wild.
PAWS will try to time the release to be outside a hunting season, said Convy, the PAWS rehabilitation manager.
But there's no guarantee she won't someday be shot or, for that matter, hit by a car.
Eric Sorensen can be reached at 206-464-8253 or firstname.lastname@example.org.