Lessons from the Winter of 2022–23: Rebuilding Mule Deer Herds After Catastrophe

By Trevor J Hubbs

The winter of 2022–23 will be remembered across the West as one of the harshest in recent memory. In Wyoming, Idaho, and parts of northern Utah, relentless snow and bitter cold combined to create a perfect storm of survival challenges for mule deer. Tens of thousands of deer perished, including entire fawn crops and mature bucks that entered the season in good shape but simply couldn’t endure months of deep snow and subzero temperatures.

For biologists, managers, and hunters, that devastating winter was more than a tragedy, it was a hard-earned lesson in how fragile mule deer populations can be, and how recovery depends on patience, sound management, and continued conservation work.

1. Why was the Winter of 2022–23 Was So Deadly?

Mule deer are remarkably adapted to the West’s tough winters. They grow thick coats, slow their metabolism, and migrate to lower elevations where food is easier to find. But the winter of 2022–23 overwhelmed even those natural defenses. Combined with the unique phenomenon of the harshest weather and conditions at lower elevations than normal, mule deer and pronghorn we drastically affected.

In many regions of western Wyoming and southeastern Idaho, snowpack reached record levels: five to eight feet deep in some valleys. Bitter cold followed, with temperatures rarely rising above freezing for months. Crusted snow made it impossible for deer to reach the sagebrush, bitterbrush, and other forage buried beneath.

Without access to food, deer burned through fat reserves and muscle just to stay alive. Fawns and old deer were the first to die, followed by even healthy adults as the cold persisted into late spring. In some monitored herds, biologists recorded fawn survival rates below 10%.

2. The Domino Effect of a Harsh Winter

When winter mortality spikes, it triggers a chain reaction that ripples through herds for years:

Reduced recruitment: With few surviving fawns, local populations can take five to seven years to recover even under ideal conditions.
Weakened age structure: Mature bucks and productive does often succumb in prolonged winters, affecting the genetics and breeding potential of the herd.
Winter Range Access: Deep snow can alter traditional travel routes for deer and make their winter ranges unavailable and displace deer to lesser habitats or expose them to increased predation and vehicle collisions.
Migration disruption: Deep snow forces deer to shift routes or abandon traditional winter ranges, exposing them to predators and vehicle collisions.
Habitat stress: Overgrazed or degraded winter ranges recover slowly, especially when drought follows.

For wildlife managers, that means adjusting tag quotas, shortening seasons, and sometimes closing units altogether to give herds time to rebound. The Mule Deer Foundation supports state fish and game professionals when they madethese tough decisions in 2023 and 2024, recognizing that short-term sacrifice is necessary for long-term sustainability.

3. How State Agencies Responded

Wyoming and Idaho both implemented significant changes following the 2022–23 winter. Quotas for antler-less and general-season buck tags were reduced, and some units moved to limited-quota or draw-only systems.

In Wyoming, biologists also intensified their collaring and migration monitoring efforts to understand how deer adapted, or failed to adapt, to the severe conditions. In Idaho, winter feeding programs were activated in targeted areas to help prevent starvation while avoiding the unintended consequences of concentrating deer too tightly, which can spread disease.

In Idaho, winter feeding programs were activated in targeted areas to help prevent starvation while avoiding the unintended consequences of concentrating deer too tightly, which can spread disease. In Wyoming, biologists also intensified their collaring and migration monitoring efforts to understand how deer adapted, or failed to adapt, to the severe conditions..

The lesson for hunters: recovery takes time. Herds that lost half their population in one winter can’t bounce back in two or three years. Responsible hunting pressure and habitat improvement must work hand–-in–-hand to restore balance.

4. What Hunters Can Do to Help Recovery

For hunters who live and breathe mule deer, patience and stewardship are the best tools in the aftermath of a winter die-off. Here’s how you can make a difference:

Respect reduced tag allocations. Fewer tags don’t mean lost opportunity, they mean managers are protecting the foundation for future hunts.
Volunteer for habitat projects. Fencing removals, bitterbrush planting, and sagebrush restoration improve the very ranges that sustain deer through harsh winters.
Support migration corridor protection. Many deer died in 2023 trying to reach winter range that had been blocked by development or degraded by overuse. Protecting these routes ensures herds can adapt to changing weather.
Respect seasonal closures. Stay away from deer during the late-winter/early spring to help them conserve energy. Keep dogs away from wintering animals.
Report winter conditions. Hunters are the eyes and ears on the ground. Sharing observations of winter-kill or habitat conditions helps biologists make better decisions.

By taking a conservation-minded approach, hunters become part of the recovery process, not just observers of the decline.

5. Understanding the Recovery Timeline

Mule deer herds rebound slowly, and that’s natural.. It often takes five to ten years for populations to regain stability after a severe die-off, especially if winters remain tough or drought limits summer forage.. Biologists track multiple indicators, including fawn–-to–-doe ratios, buck age structure, and body fat reserves, to determine true recovery progress.

In short: nature takes its time. The key is giving herds the space and support they need to rebuild naturally, without adding unnecessary pressure.

6. Conservation After the Storm

The Mule Deer Foundation’s mission becomes even more critical after winters like 2022–23. MDF and its partners have ramped up efforts to restore winter range, improve migration corridors, and build more mule deer in heavily impacted areas.

By working with state agencies and local communities, MDF has helped replant native browse species, remove invasive weeds, and rebuild wildlife-friendly fencing on key winter ranges across Wyoming and Idaho. These efforts help ensure that when the next hard winter hits; and it will; herds have stronger, more resilient habitat to fall back on.

Good Luck!

As always, good luck this fall everyone and remember to send any success pictures or stories from the field to [email protected] and you could be featured on our website or in our magazine. If this article or any of our articles have helped you become a better hunter or conservation steward, consider becoming a member of the Mule Deer Foundation for only $35 dollars a year. Click here to join: https://muledeer.org/product-category/membership/

Trevor Hubbs

Trevor is the Communications Manager and Editor for the Mule Deer Foundation and Blacktail Deer Foundation. He grew up hunting and fishing the Ozark Mountains for quail, ducks, and bucks. Now he goes west for mule deer as often as he can draw a tag.