Utah wildlife officers assessed and GPS collared 1,901 wild animals in a single winter, from deer to mountain goats across six species, the largest effort of its kind the state has ever carried out.

Fly low over snow-covered sagebrush in southern Utah on the right morning during the winter of 2024–25, and there was a decent chance you’d see a helicopter crew fire a net gun and a wildlife team assess an animal before releasing it a few minutes later. That capture-and-assessment work involved 1,901 animals between November 2024 and March 2025, across six species and dozens of mountain ranges, and it is the largest single winter of big-game capture work Utah’s wildlife agency has recorded.

The Utah Division of Wildlife Resources (DWR) confirmed the final tally in a news release published in March 2025: 1,130 mule deer, 363 pronghorn, 195 elk, 107 bighorn sheep, 54 mountain goats and 52 moose. That is the brief’s headline figure and the six species, verified, and it beats the agency’s previous record of 1,779 animals from an earlier winter capture season, so “largest ever” holds up against DWR’s own numbers rather than being a loose superlative.

That is close to two thousand wild animals handled, measured and released in a single season.

It is worth being precise about what the number describes. These are not all newly collared animals; some were recaptured to swap a failing collar or take another round of health measurements. DWR’s release describes the total as animals assessed and GPS collared, a category that covers both first-time captures and check-ins on animals already wearing a collar from a previous winter.  The agency didn’t break down how many of the 1,901 fell into each category, so the true number of brand-new collars deployed this winter is somewhat smaller than the headline figure suggests.

How the capture work actually happens

The method is blunt and quick by design. Crews use helicopters fitted with net guns, working from November through March when big game has moved down to lower elevations and cooler weather helps animals recover faster from the stress of being chased and handled. Once an animal is netted, a ground or air crew moves in for a short physical exam: body fat measurements, blood and fecal samples for disease testing, a pregnancy check on does and ewes, and, if it doesn’t already have one, a collar.

Kent Hersey, DWR’s big game projects coordinator, put the priority plainly in the agency’s release: “When we do capture work, we make a concerted effort to minimize chase times and to keep all capture-related stress to a minimum.” The whole handling window for a single animal is typically a matter of minutes.

Speed matters for another reason. Body condition going into winter is one of the strongest predictors of whether a deer survives it, and DWR biologists use the fat measurements taken during capture to gauge how a herd is likely to fare before spring green-up arrives. According to Hersey, that data “has informed our management decisions” on issues from permit numbers to supplemental feeding in hard winters.

Why Utah tracks this closely

The captures aren’t a one-off headline exercise. They feed a longer-running programme, the Utah Wildlife Migration Initiative, that maps where deer, elk and pronghorn actually move across the year rather than relying on where hunters or wildlife officers happen to spot them. Makeda Hanson, the initiative’s coordinator, described the payoff in DWR’s release: “The GPS collars provide crucial data that informs planning for sustainable land use, transportation, energy, residential and commercial development, recreation and habitat improvement.”

In practice, that has meant identifying migration bottlenecks where highways cut across historic deer and elk routes, feeding into decisions about where to build wildlife crossing structures and fencing. It has meant tracking pronghorn herds closely enough to justify relocating some animals between ranges, as DWR did with 310 pronghorn from the Parker Mountain herd during this same capture season. And it has meant building a running record of pregnancy rates and fawn survival that biologists can compare winter to winter, rather than guessing from harvest numbers alone.

Disease surveillance sits underneath all of it. Blood and tissue samples collected during captures feed into chronic wasting disease monitoring, a slow-moving prion disease that has become one of the most closely watched threats to deer and elk herds across the western United States. There is no vaccine and no cure for it once a herd is infected, so early detection through exactly this kind of sampling is one of the few tools wildlife agencies have. A capture season this large means a correspondingly large disease-testing sample, which is itself part of why DWR frames 1,901 as a milestone worth publicising rather than a routine count.

Drought is the other pressure running through all of this work. A dry autumn leaves less forage before winter, which shows up directly in the fat measurements crews take at capture, and a run of dry years can push migratory herds to shift their routes earlier or further than usual. Collar data lets biologists see that shift happening in near real time rather than reconstructing it after the fact from a smaller deer count the following autumn.

DWR’s 2025 release does not state how many of the 1,130 captured deer received a new or replacement collar or how many collars were transmitting statewide. Dividing the capture count by the agency’s population estimate yields roughly one capture for every 260 deer, not one live collar for every 260 deer. It therefore cannot establish the state’s current GPS-tracking coverage.

A snapshot, not a running total

What DWR does have is a clean year-on-year comparison: 1,779 animals in the prior record season, 1,901 this time, an increase of 122 animals. Whether that number keeps climbing, plateaus or drops depends on funding, helicopter availability and how many collars from earlier winters are still working well enough not to need replacing.

Somewhere in Utah’s back country right now, a deer, an elk or a mountain goat wearing a GPS collar placed or checked through this programme may be moving through terrain no person will see this week, while a biologist follows its reported location.

Correction, 15 September 2026: An earlier version said Utah was receiving location updates from roughly one in every 260 deer and implied that all 1,901 captured animals received new collars. The source reports captures and assessments but does not publish the number of currently transmitting collars.