WYOMING — The Wyoming Migration Initiative (WMI), an organization within the University of Wyoming, is tracking the migration of a seasonal resident who is making a 175-mile trek from the Red Desert to the Teton Range.
In a Wednesday social media post, WMI shared an update on Mule Deer 665’s annual spring journey. The 5-year-old doe is pregnant with twins and began the migration from her winter range on April 9. The most recent check-in states that Deer 665 took a break on May 7 in the Hoback Basin.
Greg Nickerson with WMI told Buckrail that it takes a bit of time to create and post the migration maps because he coordinates with a graduate-student researcher, an in-house cartographer and a student cartographer in Oregon. He said it will still be a few weeks before the final maps are released.
Deer 665 covered about 67 miles on her first week, crossing a highway and four creeks. According to WMI, the deer began her migration nearly a month earlier than last year, which could be attributed to the mild winter experienced throughout Wyoming.
The most recent update shows that 665’s fourth travel week included a few challenges, like crossing the Fremont Lake bottleneck — a quarter-mile-wide gap between Fremont Lake and the town of Pinedale — and the 100-yard-wide Willow Lake bottleneck. She then crossed WY352, swam across the Green River and passed Rim Station, before ending her fourth week of travel in the Hoback Basin at Raspberry Ridge. At that point, she had covered 135 miles in 29 days.
“Deer 665 wrapped up her fourth week of migration on May 7 at Raspberry Ridge in Hoback Basin, one of her favorite places on this entire migration route,” WMI wrote on social media. “She last passed through this area on October 21, 2025.”
This is the deer’s 10th time on this migration path. In March, WMI captured 665 for a health checkup, and that is when it became known she was pregnant with twins. Last year, she arrived at her summer range on Teton Pass on June 8. More updates on her trek will be shared as they become available.
