Do Montana Elk Escape onto Private Land? The Answer Differs Between Two Herds

For each herd, the share of archery-season GPS fixes recorded on closed ground exceeded what that ground's fraction of the range would predict. The study tracked the whereabouts of collared cows; it did not establish whether they fled onto closed ground. Closed land in the Missouri Breaks accounted for 3% of the range during archery season but contained 32% of the herd's archery fixes. A single Larb Hills block occupied 21% of the range and contained 50% of the archery fixes plus 34% of the rifle fixes. We set those location percentages against the corresponding range percentages and developed a brief map check to measure closed ground within a unit.

Proffitt and colleagues, researchers at Montana Fish, Wildlife and Parks, used nets to capture 25 adult cows from each herd in February 2013. The two adjacent herds lived in Montana's northeastern region. GPS collars recorded an hourly fix through February 2015. Researchers recovered tracking data from 46 elk within a study area measuring 4,963 km2. Fifteen of the elk died over the two years, with hunter harvest accounting for most deaths. Hunters legally harvested 9 of them: 8 on hunter-accessible ground and 1 on private ground unavailable to public hunters.

Concerns about herd size prompted the research. Managers almost doubled the available antlerless licenses during 2004 to 2006. According to unpublished agency figures cited in the paper, hunter success dropped from 40% in 2007 to 10% in 2014, yet the count in 2014 remained 30% over the herd objective. Some stakeholders attributed the problem to elk occupying places hunters could not access. Researchers divided the range among three access categories. The accessible category included huntable public ground and private parcels enrolled in Montana's Block Management program, along with other private parcels that did not limit public hunting access. The no-access category combined private ground under paid leases with one wildlife-viewing area on public land. Private parcels requiring a trespass payment or allowing only friends and family fell into the restricted category. Throughout this article, closed means the latter two categories combined.

Closed land in the Missouri Breaks consisted of scattered small private parcels plus a wildlife-viewing area measuring 5.1 km2. Together, they occupied 3% of the range during archery season. In Larb Hills, a continuous tract of about 150 km2 lay close to the middle of the seasonal ranges; closed land accounted for 21% of the range there.

The abstract opens by reporting that accessible land contained 68% of the Missouri Breaks fixes during archery season and 91% during rifle season. Viewed alone, those percentages suggest that cows mostly occupied places hunters can reach. Setting use against acreage shows heavy use of closed land. If acreage alone determined the distribution of fixes, land covering 3% of the range would contain about 3% of them. Instead, closed land contained 32% during archery season. That is roughly 11 times its fraction of the range, calculated as 32 divided by 3. Because the paper rounds the range percentages to whole values, the actual multiple could fall between about 9 and 13. For rifle season, the researchers reported that no-access land occupied less than 5% of the range but contained 9% of the fixes, exceeding 1.8 times its range share. Applying that calculation to Larb Hills yields 50 divided by 21, or about 2.4 during archery season. This multiple is smaller because closed land already occupied a fifth of the range. Nevertheless, half the archery fixes in Larb Hills fell beyond public hunters' reach, compared with about a third in the Missouri Breaks.

A baseline based solely on area leaves out cover, roads and terrain. The multiple therefore describes the scale of use without separating out the effect of access. The researchers' models account for distances from cover and roads, terrain roughness, and land cover. Their population-level models still assigned no-access ground a positive coefficient within home ranges. This standardized effect indicates stronger selection as its value increases. The Missouri Breaks values were 0.93 during archery season and 0.54 during rifle season; the corresponding Larb Hills values were 1.39 and 1.03.

The researchers also modeled each tracked cow separately for each season-year. In the Missouri Breaks, selection favoring no-access land appeared in only 46% of elk-years during archery season and 24% during rifle season. The paper's Table 3 reports the underlying counts as 17 out of 37 and 8 out of 33. Here, an elk-year means one cow tracked during one season; tracking that cow across both years contributes twice. For Larb Hills, the table reports 33 out of 43 and 27 out of 38. Dividing those counts produces 77% and 71%.

Individual cows also carried their patterns into the following year. Researchers tracked 17 Larb Hills cows across both rifle seasons. Among them, 13 favored restricted or no-access land during both years, while 1 favored accessible land during both years. The remaining 3 changed categories. The authors suggest this consistency could reflect a long-term adaptation that would be harder to alter through changes in hunter pressure. A claim about herd-wide selection for closed land therefore combines cows that favor it with others that do not.

Estimated annual pressure totaled about 9,679 hunter-days during archery season versus 5,324 during rifle season, giving a ratio of 1.8. Both herds selected no-access land more strongly during archery season. The authors compare this result with research elsewhere that found greater rifle-season hunting pressure alongside a larger rifle-season elk response. They suggest that seasonal effects likely track hunting pressure. Observations from two seasons at one site cannot separate pressure from the seasons' other differences. The result identifies a pattern without proving its cause.

The timing also matters. Rifle season accounted for 77% of the yearly hunter harvest in the Missouri Breaks and 79% in Larb Hills over the period described by the paper as the last decade. Those agency figures were unpublished, the years were unspecified, and the paper dates to 2016. For rifle season, Missouri Breaks elk relocated to ground with greater hunter access. More elk in Larb Hills remained where hunting access was restricted once archery season ended. The authors say this reduced the number available to rifle hunters.

The evidence comes from one study tracking two adjacent herds across two years of archery and rifle hunting. The 3% and 21% values represent two cases rather than a curve. Researchers collared adult cows exclusively. Bulls were outside the study and may act differently. Our calculation divides each location percentage by its range percentage, relying on rounded values and a baseline based solely on area. The paper does not present that calculation. Closed land in the Missouri Breaks includes a wildlife-viewing area on public ground. The text does not separate fixes there from fixes on private parcels, preventing attribution of the full 32% to private ground. The paper also contains a count that fails to reconcile: its Larb Hills archery follow-up reports groups of 1, 17 and 3 cows despite giving 20 as the total.

Our Montana elk table contains 22,614 rows spanning 2004 to 2025. These include hunting-district harvest estimates and statewide and regional summaries, but lack an ownership or access field. Our public-access tables include Iowa, Illinois and Kansas, plus Missouri, Ohio and Wisconsin, and cover no other states. These data gaps prevent us from determining the size of a closed block in any Montana district, and the guide contains no FDR chart. Statewide harvest is discussed in our Montana elk and mule deer paper.

Assess the amount of closed land before concluding that the herd shifted. First, mark all parcels unavailable to public hunters. Include posted private parcels and land under paid leases, refuges where hunting is prohibited, and private parcels admitting only friends and family. Divide their combined acreage by the acreage used by the herd. Use the state wildlife agency's seasonal range map when one is published; otherwise, use the hunting district as a rough substitute. Second, locate the biggest continuous closed tract and measure its distance from the range's middle. A tract of 150 km2 amounts to about 37,000 acres, or approximately 58 square miles. Third, determine which hunting season brings greater pressure to your unit, using hunter-days when the agency supplies them. In this study, archery brought both greater hunting effort and a stronger elk response.

Next, set your measurements beside these two cases. They provide two observations without predicting an outcome. In the Missouri Breaks, small scattered pieces of closed land occupied a few percent of the range, and accessible land contained most fixes. Under that arrangement, examine cover, roads and hunting pressure where access is open before blaming the fence. In Larb Hills, a single tract near the range's middle closed off a fifth of the range. Closed land there contained 50% of the fixes during archery season and 34% during rifle season. The researchers caution that restricting hunter access across a relatively small area may affect elk distribution disproportionately. We have no observations between these cases and do not connect them with a line.

Among individual cows, greater home-range accessibility accompanied stronger archery-season preferences for cover, greater distance from roads, and rougher terrain. Yet accessibility accounted for only 5% to 13% of the variability in those selection coefficients. The guide to whitetail collar studies makes a comparable point about deer: the studies emphasize the portion of a deer's range visible to hunters more than the number of hunters who checked in.