Retrofitting busy highways to let wildlife travel safely, too

COLLEGIATE PEAKS SCENIC BYWAY, Colo. - U.S. Highway 285 was once a death zone for the dwindling herds of elk and mule deer on Colorado’s Western Slope. But today it offers a lifeline, helping them travel from their summer range high in the mountains to winter foraging grounds along the Arkansas River.

For the past year, a tunnel dipping under three lanes of speeding traffic has beckoned. And as frost descended recently on subalpine meadows and glittering-gold aspen, a huge bull elk, measuring at least nine feet from antlers to hoofs, entered the structure ever so cautiously. Infrared cameras on both ends captured his meandering.

"Yes!" exulted Mark Lawler, an environmental specialist with the state transportation department, sitting under the 25-foot-wide tunnel arch and watching images pop up on his laptop. The ground there was marked by coyote, deer and even squirrel tracks, more proof of success. But Lawler was focusing on the elk's safe passage. He "won't be hit by someone on the highway."

The $3.5 million project is one of several planned for Colorado's ever more crowded roads, on which some 4,000 bears, bighorn sheep, coyotes and myriad other animals died last year. The cost of the carnage exceeded $80 million, according to state officials.

Across the country, as development continues to encroach on natural areas, wildlife-vehicle collisions are taking a massive toll. More than 1.9 million animal-collision insurance claims were filed in fiscal 2019, a State Farm report found, with some researchers estimating the annual price tag of the resulting human fatalities, wildlife mortality, injuries, vehicle damage and other costs at almost $10 billion.

Yet advances in satellite tracking technology are helping biologists to better understand how many animals rely on corridors - strips of land that link habitats - and how wildlife crossings over and under roads are essential to reconnect these shrinking settings. Federal and state officials, conservationists and landowners are now partnering across borders on remedies.

"Our ecosystems are in crisis due to habitat loss, deforestation and, of course, climate change," said Sen. Tom Udall, D-N.M., who in May introduced a Wildlife Corridors Conservation bill with bipartisan support. The measure would provide federal land managers the authority to establish corridors, set aside $78.5 million in funding, in part for regional projects, and order the creation of a federal wildlife connectivity database.

"The science is clear that corridors help protect our most vulnerable species," Udall said in an interview.

Research and video feeds show that specially designed crossings have protected scores of pronghorn antelope in Wyoming, panthers in Florida, mule deer in Nevada, moose along "Slaughter Row" in Utah and grizzly and black bears in Montana from oncoming cars and trucks. Mortality dropped by as much as 90%, studies show.

Beyond maintaining populations, such projects ensure that ailing ecosystems retain biodiversity, scientists note. The strategy works for flora, too. A new study based on a decades-long experiment that restored longleaf pine savanna in South Carolina found that fewer plants went extinct in connected habitats.

“We need to create, or support, maintaining wildlife movement and connectivity at landscape scale because it has long-term genetic consequences,” said Rob Ament, road ecology program manager at the Western Transportation Institute at Montana State University, who is consulting on a project in Asia that will benefit rhinos, tigers and elephants. “We built our interstate system in the 1950s and 1960s before we knew this, and now we must retrofit it to connect landscapes across major highways.”

Under a 2018 secretarial order, the Interior Department is funding work in 11 Western states to identify wildlife corridors and what threatens them, and to create plans and partnerships to preserve such areas. Casey Stemler, a senior adviser in the U.S. Fish and Wildlife Service, recalls asking those states to list the key risks to the corridors, "and they all said highways." A Senate transportation bill includes $250 million for a five-year wildlife-crossing pilot program.

New Mexico and Colorado officials are collaborating with tribes, the National Wildlife Federation, sportsmen's organizations and landowners pushing for special management areas to protect corridors across three national forests - Rio Grande in Colorado and Carson and Santa Fe in New Mexico. Collectively, they represent one of the least fragmented wildlife landscapes in the continental United States, with elk, bighorn sheep, mule deer, pronghorns, lynx, black bears and cougars traveling among them.

"When you have two areas that promote wildlife movement from forest to forest, region to region, and state to state, it sets a strong precedent," said Jeremy Romero, the federation's regional connectivity coordinator. "We are hoping this can be a West-wide model."

States are independently prioritizing wildlife corridors and crossings, too. New Mexico Gov. Michelle Lujan Grisham, a Democrat, in March signed legislation directing her transportation and game and fish agencies to work with tribes in using GPS data from wildlife fitted with electronic collars to identify roads that hinder migration. A plan listing the top proposed corridor projects is to be submitted to the legislature by January.

And under an executive order from Colorado Gov. Jared Polis, in August, his natural resources department is studying migration patterns in advance of developing new policies. "We want to ensure conservation of big-game winter range so we can grow our outdoor recreation economy and protect the diversity of our wildlife," Polis, a Democrat, said in a recent interview.

Meanwhile, engineers in Southern California are designing the world's largest animal crossing. The $87 million overpass, which will span a 10-lane Los Angeles freeway, is a bid to save the region's mountain lions by reconnecting habitats in the Santa Monica Mountains with those to the north. Other creatures also are expected to traverse it.

Roadway ecologists emphasize crossings' cost-effectiveness. Every vehicle-elk collision avoided meant $17,483 per kilometer per year in car repairs and medical expenses averted, a 2009 Montana study found. With moose, the figure jumped to $30,760.

"A lot of these structures, we've done the math on them and they can effectively pay for themselves in a decade," said Hall Sawyer, a research biologist at West Inc., an environmental consulting firm in Cheyenne, Wyoming.

Key to crossings' success are fences that direct wildlife toward the site and structure, metal guards that keep animals off roads at intersections, and earthen ramps that allow them to exit.

A couple of hours west of Colorado Springs, the project along Highway 285 has two miles of eight-foot fencing on either side of the asphalt to funnel animals into a trio of box culverts constructed in the late 1960s. Its location near the small town of Buena Vista is not happenstance: Lawler compared law enforcement crash data on injuries from wildlife-vehicle collisions and carcass removal information collected by maintenance crews, then talked with wildlife managers in the area and coordinated with private landowners.

The effort paid off: The bodies of elk and mule deer no longer litter the road. Instead, Lawler watches remotely as they amble with little danger through the tunnel.

The state transportation department plans to hire a firm next spring to track data from the structure's cameras and better quantify the crossing's effectiveness.

“It would be great if someday wildlife treatments are seen as stand-alone projects,” said Lawler, glancing up at the pinyon- and juniper-covered hillside where animals case the underpass for safety. “I can see that day coming.”