Mule Deer Doe Breaks Record For Farthest Migration

Apr 16, 2018

The doe traveled 92 miles farther than the longest mule deer migration route known.
Credit Wyoming Migration Initiative

After walking the usual migration route from the Red Desert to Hoback Junction near Jackson, Mule Deer Doe #255 kept going to Island Park, Idaho, traveling a total distance of 242 miles. That's 92 miles farther than the known-longest mule deer migration route. All summer, scientists waited to see if she’d migrate back or if she had just joined a different herd. 

“But then in the first week of August, her collar failed,” said Matt Kauffman, director of the Wyoming Migration Initiative. “She was just lost.”

But a year and a half later, they found her back on her winter range, proving the journey was a true migration.

“My graduate student had listened so frequently for Deer #255 that she’d memorized the serial number on the collar. And she looked at the collar, read off the serial number and immediately knew that that was Deer #255. And so that was really exciting,” said Kauffman.

“Outwardly, she looks just like any other mule deer doe,” said Wyoming Game and Fish Department Biologist Mark Zornes with a laugh.

Zornes said, Doe #255 is now migrating somewhere between Steamboat Mountain and Highway 28, but this time she’s pregnant with fawns.

“The interesting question is, will she give birth to fawns and will she successfully rear that fawn and bring it home to the Red Desert for the winter and perhaps pass that trait along that she obviously has?” said Zornes. 

To hear an interview with Matt Kauffman where he tells Deer #255’s whole story, listen to this week’s episode of Open Spaces.