12/10/2025
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Migration Tracking Week 5 🦌🦌🦌🦌🦌 Happy holidays migration fans! We are thrilled to report that Deer 665 has arrived on winter range and completed her fall 2025 migration. In this final stretch she departed her Prospect Mountains stopover and spent four days migrating to Superior, Wyoming. Last week 40 people guessed she would migrate between 0 and 38 miles in week 5. Her actual distance traveled was 48 miles for the week.
This concludes Deer 665’s fall migration from the Tetons to the Red Desert. Her final migration distance was 175 miles, and the duration was one month and five days from Oct. 13-Nov. 16. In total she spent 35 days migrating with 11 days of stopover.
Deer 665 will likely stay where she is until March or April, sheltering in one of the best winter ranges in southwest Wyoming with approximately 1,800 other mule deer. Assuming all goes well for Deer 665 on winter range, our next migration update for her will happen after the grass turns green in the spring of 2026.
**We know Deer 665’s story and maps strike a nerve. Thanks to all of you, her fall 2025 migration tracking has received more than 2.5 million views. We’re curious though, what makes you care about Deer 665’s story? We’d be grateful if you would take a second to share what inspires or fascinates you about Deer 665 in the comments.**
PLAY-BY-PLAY for Deer 665’s last week of fall migration: For this stretch from day 31-35, Deer 665’s daily distance was 14 miles, then 12 miles, 10 miles, and 9 miles on her final day of migration.
Nov. 12-13 took her across WY 28, near the False Parting of the Ways on the Oregon Trail and the point where Sublette, Fremont, and Sweetwater counties meet. WYDOT has retrofitted portions of WY 28 highway with wildlife-friendlier fencing to make it easier for migratory deer to cross.
From Nov. 13-14 Deer 665 crossed the Jack Morrow Hills and the Jack Morrow Creek drainage. The Shoshone place name for this creek is Senaranden Ohgway, which translates to Aspened Creek.
On Nov. 14-15 Deer 665 traversed Lafonte Canyon and Johnson Canyon. She then headed through Sand Gap on the flank of Steamboat Mountain, a massive butte overlooking the Killpecker Sand Dunes and the Red Desert.
Now in the home stretch, Deer 665 passed by South Table Mountain on Nov. 15 and entered the Leucite Hills. She finally arrived to Horsethief Canyon near Superior, Wyoming on Nov. 16.
Take a moment to recall how she migrated here from the Teton Range, across Jackson Hole and the Gros Ventre Range, Hoback Basin and the entire Green River Basin. What a journey, made possible by generations of stewardship on private ranches and public lands, and the groundswell of support for migration conservation efforts in recent years.
Deer 665 and her herd directly benefit from numerous conservation easements and hundreds of miles of new wildlife-friendly fence projects in the Green River Basin. These science-based efforts are why we and many other partners and independent colleagues track these big game animals, to advance the conservation of migratory herds all across Wyoming and the West.
ABOUT SUPERIOR: Deer 665’s winter range is in the hills outside of Superior, Wyoming a historic coal mining town of about 200 people. We’re not certain why she picks this winter range so close to people, but it’s probably because the habitat overlaps with part of the winter range of her mother, Deer 512.
This ties back to the animation we shared a few weeks ago on Nov. 7 When Deer 665 was still a fawn in the fall of 2021, she and her mom Deer 512 spent the winter together in this area. Deer 665 was first collared on March 8, 2022, and the two moved together on winter range until March 20 of that year.
They even started Deer 665’s first northward spring migration together, until mom bolted on March 26, 2022, leaving the fawn on her own. The animation in the comments shows how this played out, resulting in Deer 665 doing a 220-mile exploratory migration to Ririe, Idaho for summer 2022, and ultimately selecting her own summer range in the Tetons that she has returned to ever since.
So while Deer 665’s summer range is distinct from her mother's, her winter range is very close to where her mom first brought her at six months old to survive the cold season.
As a yearling, deer 665 was one of the 70 percent of deer who survived on this winter range in the horrendous winter of 2022-2023, as compared to 30 percent adult survival at other wintering grounds in southwest Wyoming. Over time that survival at the herd level has allowed the deer near Superior, Wyoming to make some of the most impressive migrations in the lower 48 states.
Deer 665’s ultra-long-distance migration sets her apart from the rest of the Sublette Herd, and all the other Wyoming mule deer that travel short or medium distances.
At the same time, all of these journeys inspire us with the lengths migratory animals go to survive, reproduce and carry the herd forward, and the ways people can work together to help keep these migrations intact long into the future.
Thank you all for following along and sharing Deer 665’s amazing story. Here’s wishing Deer 665 and all of you a safe and healthy winter!
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The data for this map is thanks to collaboration between our team at the University of Wyoming and biologists with , , Bureau of Land Management - Wyoming, and USGS Cooperative Fish and Wildlife Research Units.
Cartography by Naim Ferris and Joanna Merson, our Wild Migrations atlas partners at the Department of Geography, University of Oregon InfoGraphics Lab, with WMI's Ian Freeman.
The Red Desert Mule Deer Study is generously supported by many partners and funders, including:
Knobloch Family Foundation,
George B. Storer Foundation,
Safari Club International Foundation and 100 Hunter Legacy Endowment Fund,
Muley Fanatic Foundation Headquarters,
Muley Fanatic Foundation – Southwest Wyoming Chapter,
Muley Fanatic Foundation Upper Green Chapter
10 Country Chapter of The Muley Fanatic Foundation,
Mule Deer Foundation of Wyoming,
Mule Deer Foundation Headquarters,
SITKA Gear,
National Science Foundation,
Biodiversity Institute of UW – Don and Judy Legerski Fellowship,
Wyoming NASA Space Grant Consortium Graduate Fellowship,
the UW Science Initiative Graduate Fellowship,
USGS Wyoming Landscape Conservation Initiative,
Wyoming Governor's Big Game License Coalition,
Teton Conservation District,
Wyoming Game and Fish Department,
Bureau of Land Management – Wyoming,
The Nature Conservancy,
The Pew Charitable Trusts,
and Sweetwater Royalties, Ghost Town of Superior Wyoming, and Wildcat Coal (for private land access).
