A new study confirms what wildlife managers have suspected all along: Wily elk from Grand Teton National Park migrate to the south end of the National Elk Refuge earlier than most, and are much more successful at avoiding hunters.

Penned by Bruce Smith, retired refuge biologist, the investigation shows that the elk leave for the refuge when park forage dwindles, not when snow pushes them south. Smith’s paper appears in a recent edition of Northwest Science.

The study comes after National Elk Refuge officials started a limited-range weapon hunt on the south end of the refuge this fall. The goal of the hunt is, in part, to target elk from the Grand Teton herd segment that see very little hunting pressure. The hunt is also designed to move animals off the south end of the refuge in fall, preserving winter forage and reducing the need for supplemental feed.

The south-end hunt has, thus far, yielded mixed results. Though hunters have harvested fewer than 10 elk on the south end of the refuge, there is evidence that the presence of hunters is pushing elk farther north. Refuge biologist Eric Cole reported between 900 and 1,700 elk on the south end in late October and early November.

“Without this [south-hunt] disturbance, there would likely be more than 2,500 elk on the south end of the refuge rather than the current 1,700,” he said in a statement.

On Tuesday, two large groups of elk were in the hunt area just west of Miller Butte. One other group was in a no-hunt zone on the west side of Flat Creek near the National Museum of Wildlife Art and another closer to Jackson in the middle of the refuge near the Miller House.

Refuge officials say that most of these south-end early arrivals come from the Grand Teton herd segment. And Smith’s study confirms that Grand Teton elk do indeed avoid hunters more successfully than animals from the Yellowstone, Gros Ventre and Teton Wilderness herd segments.

An in-depth review of refuge feeding practices, adopted this year, aims to reduce the Grand Teton segment by approximately 1,000 animals. That review also opened the refuge to bison hunting in an effort to curtail that species’ impact on the wintering grounds.

Biologist Smith’s study, conducted from 1990 to 2000, tracked the elk using radio collars as they migrated. Smith also took surveys of vegetation in Grand Teton National Park.

“There’s kind of been a long-standing understanding that the Grand Teton park elk were likely the most difficult to harvest of the herd segments,” said Smith.

Elk from safe areas in the park can reach the safe zones of the refuge by traveling as few as about four miles. Hunting is not allowed west of the Snake River in Grand Teton, but shooting does take place east of the Snake on the Kelly Hayfields and has historically been allowed on the northern portion of the refuge. Those hunts have produced “firing line” scenes where multiple shooters target migrating groups in open country.

In contrast, most other elk in the Jackson elk herd are hunted in their summer range, as well as during their migrations, often long and perilous journeys.

Smith found that the Grand Teton elk migrate in two groups, early and late. Though the earliest migrators theoretically spend more time in hunt areas, hunters only managed to harvest 4.8 percent of those animals compared to 11.3 percent of animals that migrated later. These early migrants often choose corridors through housing developments and other areas where hunting isn’t allowed.

What wildlife managers didn’t know is why Grand Teton elk move south so early. Smith found that, while most high-elevation elk (those outside Grand Teton) start their migration when snow starts accumulating, Grand Teton elk migrate when forage gets depleted. Vegetation levels were down 62 percent on average when elk migrated out of Grand Teton National Park.

“One would not think that they would have to leave,” said Smith. “Snow isn’t limiting their ability to forage. By sampling vegetation, we were able to determine that it was probably initiated by the depletion of forage west of Snake River, more so than by snowfall.”

Smith said the forage in Grand Teton gets hammered especially hard because elk from Yellowstone and the Teton Wilderness move down onto the Grand Teton segment’s summer range in the early fall, sometimes staying there for several days or several weeks.

“It greatly increases the number of hungry mouths there that are feeding on the vegetation that is left,” Smith said.

Early migrants are not only more successful at avoiding hunters, but likely have a better chance of surviving the winter because they access all the ungrazed, irrigated forage at the south end of the refuge.

Smith said the elk don’t necessarily make a conscious decision to migrate early using these paths, but the behavior increases the chance that those animals will reproduce.

That behavior then gets passed down to offspring generation after generation.

The refuge’s goal is to improve the habitat on the 25,000-acre reserve, now heavily trammeled in winter by bison and elk. Better habitat would allow elk to spread out and feed naturally, rather than relying heavily on the traditional supplemental feeding program. Such dispersion also would help protect the Jackson elk herd from diseases, like brucellosis that now infects it, and chronic wasting disease, that has not been discovered but which could be devastating.

Under the management program, the U.S. Fish and Wildlife Service, which operates the refuge, will try to meet Wyoming Game and Fish Department population goals after accomplishing its principal objectives.

While it remains to be seen whether the south-end hunt will result in the harvest of more Grand Teton animals, breaking their early migration pattern would be difficult, according to Smith.

One answer could be to end supplemental feeding.

“A lot of these issues may well resolve themselves if the elk weren’t fed in the winter,” said Smith.

Over time, the herd size would be reduced, leaving more forage in Grand Teton National Park. Further, elk wouldn’t have the memory of feedlines drawing them to the refuge each year. But, with some elk living as long as 17 years, the early migration won’t end too soon, Smith said.