Wildlife biologists shed light on how solar developments affect big game
As solar energy surges, wildlife biologists in Wyoming have published a paper highlighting the challenges utility-scale solar projects pose to big game, like elk and deer.
Beginning in 2018, the researchers monitored 20 GPS-collared pronghorn in southwest Wyoming before and after construction of the 80-megawatt Sweetwater Solar Facility, the first utility-scale solar development in the state. They found that the facility – which was enclosed with a chain-link fence as required – resulted in the direct loss of about 550 acres of habitat and a roughly 40% drop in pronghorn activity within 1 to 2 kilometers of the site.
Hall Sawyer is a research biologist with Western Ecosystems Technology and the lead author of the paper, which was published in April in the journal Frontiers in Ecology and the Environment. He says the case study shows that fenced solar facilities can directly and indirectly affect habitat and create movement barriers.
“We really didn’t expect this sort of outcome,” he said during a recent webinar with The Wildlife Society in reference to the indirect loss of habitat. “Mainly because the amount of disturbance associated with the solar sites is really low, compared to other forms of disturbance, like oil and gas drilling. There’s not a bunch of traffic. There’s not a bunch of noise. There’s not a bunch of lights.”
Before the facility was constructed, 69% of resident pronghorn used the area, he said, and they subsequently had to modify daily and seasonal movement.
When possible, Sawyer suggests solar projects be built outside big game habitat, which can be ascertained by migration corridor maps. If it can’t be avoided, he advises facilities keep the area as small as possible, add wildlife paths through the fenced site, angle the corners of the fences and create buffers by roads.
“I think in general the better approach is to try and make these things permeable to wildlife, rather than trying to deter wildlife from them,” he said.
This story was produced by the Mountain West News Bureau, a collaboration between Wyoming Public Media, Nevada Public Radio, Boise State Public Radio in Idaho, KUNR in Nevada, the O'Connor Center for the Rocky Mountain West in Montana, KUNC in Colorado, KUNM in New Mexico, with support from affiliate stations across the region. Funding for the Mountain West News Bureau is provided in part by the Corporation for Public Broadcasting.