This story comes through a content-sharing partnership with Wyoming Public Media.
Very few Pronghorn are taking part in the longest annual migration in the lower 48 this year, largely because of an extremely harsh winter.
The ‘Path of the Pronghorn’ is about a 200-mile migration from the desert of the Green River Basin to the mountains of Grand Teton National Park. Usually around 200 pronghorn make the journey each spring. But this year, nine were officially counted in the park, but officials estimate there are likely at least 25.
“We were sort of on pins and needles here, while we were waiting to see if the pronghorn would return,” Sarah Dewey, a wildlife biologist with Grand Teton National Park, said. “And so the good news is that some of them did.”
Only some because the larger herd they are part of, the Sublette Pronghorn herd, died at unprecedented rates this winter. The herd was at about 40,000 animals, and after this winter Wyoming Game and Fish officials estimate about 50 percent died due to the cold and a rare bacterial pneumonia.
“We expected that we would see reduced numbers just because of the severity of the winter on the winter range,” Dewey said.
Dewey said migration is a learned behavior. So if fawns can survive the summer and migrate back to the desert, the ‘Path of the Pronghorn’ will be preserved.
“If those fawns survive till the end of the summer, and make that migration, that knowledge will be passed on to that next generation,” Dewey said.
Some estimates show Pronghorn have used this migration route for 6,000 years.
“The migration is why we have pronghorn here in Grand Teton National Park in the summer. And so they are a native species to the park,” she said. “And so of course, we want to be able to conserve them to have them be able to come back so that they can still play their ecological role in this ecosystem. “
Officials will count the Pronghorn again at the end of the summer to get another estimate. In the fall, the animals will make their migration back to the desert of southwest Wyoming.