No one knows exactly when the first elk wandered into the median around milepost 142, but after a few days they were hard to ignore. By that point, there were 25 or 30 of them spread over three miles, trapped, cars and trucks streaking by them on the interstate that flanked them north and south.
In winter it isn't unusual to spot a mule deer or two along I-70 between Eagle and Gypsum. They hover near the highway, seeking easy forage, and some seem so familiar with the hundred-yard-wide median that they might have grown up there. But a couple dozen ungulates at once is another matter entirely. The elk had come from the south side of the road in February, breaching the wildlife fencing that was supposed to keep them away. Some later found an exit; some didn't.
At least six were hit by cars over the next few weeks as they tried to escape. The calls and e-mails poured in to state highway and wildlife offices. One angry motorist sent pictures of dead elk by the roadside, demanding action. Officials from the Colorado Department of Transportation (CDOT), the Division of Wildlife and local agencies got together to assemble an evacuation plan, one that would involve fifty people and practically every oversized snowplow and emergency vehicle in Eagle County.
On March 6 a seven-mile stretch of I-70 was shut down for two hours for the operation. The wapiti wranglers cut holes in the deer fence and steered the herd through them. A few overshot the exits and kept heading west, only to be turned back by big rigs blocking their path at spanning bridges. Eventually nine elk and two deer were removed; one or two other deer outmaneuvered the wranglers and trotted away in the median, left to find their own way back to safety.
Costly as it was, the roundup near Eagle wasn't the worst traffic incident involving Colorado wildlife so far this year. In January a herd of elk tried to cross I-70 in the foothills west of Denver, near the Beaver Brook exit — a frequent and posted migration area. Although it was one o'clock in the morning, there was still more than enough traffic to put a stop to that. A semi and two cars greeted the herd. Amazingly, no motorists were injured, but sixteen elk carcasses had to be scraped off the road.
When four-legged creatures meet up with four-wheeled hunks of metal, the creatures are usually the losers. Not that anybody ever wins; nationally, wildlife-vehicle collisions cause hundreds of human fatalities and thousands of injuries every year. And they're becoming more common, as development spurs more traffic in once-remote areas. According to the Western Transportation Institute, the number of reported collisions increased by 50 percent between 1990 and 2004. Another study estimates the annual costs in property damage associated with such accidents to exceed $1 billion; the average repair bill just for vehicle damage now hovers around $2,000.
In Colorado, the number of documented collisions more than doubled over a seven-year period, from 1,700 in 1998 to nearly 4,000 in 2004 — more than ten a day. The actual figure is probably much higher; roadkill counts by highway maintenance workers suggest there may be twice as many animals killed on the state's roads than are reported to the Colorado State Patrol. On some mountain highways, particularly in the northwest and southwest corners of the state, as much as 70 percent of all auto accidents are wildlife-related.
Beyond the obvious threat posed by several hundred pounds of game crashing through your windshield, the rising rate of collisions has other implications for the survival of several at-risk species in Colorado, from the Canadian lynx to the boreal toad. Roadkill rates for some species can exceed deaths by predation or disease; they're also a strong measure of the extent to which major highways have bisected the habitat of far-roaming wildlife, creating almost insurmountable barriers to migration and leading to genetic isolation and population declines.
"The development of our transportation infrastructure, as well as land-use patterns, has really fragmented landscapes," says Monique DiGiorgio of the Western Environmental Law Center, who's campaigned for improved wildlife crossings across the state. "As the animals move in response to shifting ecosystems, one of the first things they run into is a road. The crossings are critical for reconnecting them to the land as well as avoiding collisions."
For years, Colorado highway and wildlife officials, working with academic researchers and environmental groups, have been gathering data on some of the worst kill zones and seeking solutions. The state has developed and studied different types of wildlife crossings, including underpasses consisting of corrugated steel pipe or concrete culverts. CDOT has installed miles upon miles of fencing, designed to keep wildlife away from highways or channel them to safe crossings, and replaced some older barriers that didn't work as intended. (In some cases, flawed fencing and one-way gates have actually trapped wildlife in the road right-of-way, as in the Eagle snafu.)