# Resource selection of den sites for bobcats (Lynx rufus) in the Northern Great Plains, United States

> Where does a bobcat mother hide her kittens? In South Dakota’s Black Hills, researchers found 27 dens of radio-collared females, mostly in rock crevices. The mothers chose rugged ground and spots screened at eye level by rocks and shrubs, hiding their kittens from coyotes and cougars, which hunt by sight.

Summary by Kersey Lawrence, Original Wisdom. Updated 5 November 2026. Page: https://www.originalwisdom.com/tracking-literature/2025-morrison-lehman-resource-selection-den-sites/

## Citation and access

- **Authors:** Erin E. Morrison, Chadwick P. Lehman, Brady Y. Neiles, Christopher T. Rota
- **Year published:** 2025 (published online 23 September 2024)
- **Journal or source:** Journal of Mammalogy 106(1)
- **Full citation:** Morrison, E.E., Lehman, C.P., Neiles, B.Y., and Rota, C.T. 2025. Resource selection of den sites for bobcats (Lynx rufus) in the Northern Great Plains, United States. Journal of Mammalogy 106(1).
- **DOI:** https://doi.org/10.1093/jmammal/gyae105
- **Access status:** Publisher link only
- **Where to find it:** https://doi.org/10.1093/jmammal/gyae105

## Tags

- **Species:** Mammals > Bobcat
- **Region:** North America > United States
- **Behaviour and ecology:** Behaviour; Den site selection; Denning; Habitat selection; Predator avoidance
- **Methods and technology:** Bayesian statistics; Cover boards; Deviance Information Criterion (DIC); Discrete choice models; Radio telemetry; Terrain ruggedness index; Very high frequency (VHF) radio collars
- **Data type:** New field data
- **Discipline:** Behaviour and ecology
- **Year published:** 2025

## Detailed keywords

- **Species:** Studied: bobcat (Lynx rufus), adult females and their dens. Known predators of bobcat kittens in the study area, not studied: cougar (Puma concolor), coyote (Canis latrans), golden eagle (Aquila chrysaetos). Mentioned for comparison: Canada lynx (Lynx canadensis), Eurasian lynx (Lynx lynx), Iberian lynx (Lynx pardinus), Pallas’s cat (Otocolobus manul). Vegetation in the study area: ponderosa pine (Pinus ponderosa), white spruce (Picea glauca), bur oak (Quercus macrocarpa), quaking aspen (Populus tremuloides), paper birch (Betula papyrifera), western snowberry (Symphoricarpos occidentalis), common juniper (Juniperus communis).
- **Location and habitat:** Black Hills, South Dakota, United States, within the Black Hills National Forest Fire Protection District, Northern Great Plains, and including private land. Elevation from 975 m to 2,207 m at Black Elk Peak. Coniferous forest at higher elevations; open-canopied forest and grassland lower down. Rocky outcrops are common. Road density in the Black Hills National Forest is about 3.2 km per km², roughly three times the average for United States National Forests.
- **Topics:** den site selection, natal and maternal dens, kitten survival, concealment from predators, horizontal versus vertical cover, terrain ruggedness, aspect and temperature regulation, distance to roads and human disturbance, scales of habitat selection, forest management for carnivores.
- **Statistics or models:** Random-effects Bayesian discrete choice models, comparing each den with a paired random site inside the female’s pre-birth area (a 100% minimum convex polygon of her locations in the month before birth). Models were limited to 1 or 2 variables and ranked by the Deviance Information Criterion (DIC). Fitted in JAGS through R with 95% credible intervals. Two scales: coarse (100 m radius, 3.14 ha) and local (13 m radius, 0.05 ha). Habitat measures: horizontal cover with a cover board, canopy cover with a densitometer, ground cover in quadrats, downed woody debris, slope and aspect, tree basal area with a prism, and small tree density. Map-based measures: terrain ruggedness index from a 30 m digital elevation model, distance to paved and dirt roads, and distance to water, calculated in ArcGIS Pro.
- **Data type:** New field data. Female bobcats were captured from September to April, 2016 to 2021, and 35 were radio-collared. Dens were found and measured in 2020 and 2021.

## Synopsis

### 1. What they did

A safe den is vital for bobcat kittens: the first months of life are when young carnivores are most likely to die. Yet before this study, nobody had looked at how bobcats choose den sites. The authors asked which features of the landscape and the den surroundings female bobcats select in the Black Hills of South Dakota.

They radio-collared 35 female bobcats and located them at least three times a week from March to August. When a female stayed within 500 m for four days in a row, she had probably given birth. If she stayed in the same area for one to four more weeks, the team approached to find the den.

After the mother and kittens had left, they measured the habitat at each den and at a paired random site nearby. They worked at two scales: the wider area around the den (a 100 m radius) and the den site itself (a 13 m radius).

### 2. What they found

- Dens found: 27 dens from 19 females (18 in 2020 and 9 in 2021): 6 natal dens, where kittens were born, and 21 maternal dens, used afterwards.

- Den types: 21 were in rock crevices, 4 in piles of downed wood and 2 in shrub thickets. Six of the rock crevices also had shrubs around the entrance.

- Wider area: bobcats chose areas with more horizontal cover (cover at eye level, from rocks, shrubs and the shape of the ground) and more rugged terrain than random sites.

- Den site itself: horizontal cover was again the only feature that mattered.

- Features that did not matter at either scale: canopy cover overhead, aspect (which way the slope faces), slope, distance to roads, distance to water, tree basal area and downed wood.

### 3. What they concluded

- Bobcats choose den sites that hide them from predators. Coyotes and cougars, the main predators of kittens in the Black Hills, both hunt by sight. Coyotes prefer less rugged ground, so rugged terrain may help keep them away.

- Overhead cover did not seem to matter, which suggests eagles are not a major concern. An earlier study in the area attributed only 1 of 32 kitten deaths to a golden eagle.

- Unlike some other wild cats, bobcats showed no preference for shaded north-facing slopes. Rock crevices already stay cooler and more stable in temperature, so aspect may not matter.

- Bobcats did not den farther from roads, even though humans are the main cause of bobcat deaths in harvested populations. Rugged ground may give enough protection, or the road network in the Black Hills may simply be too dense to avoid.

- In less rugged areas, cover from vegetation may matter more. There, forest management that increases tree and shrub cover at eye level may provide den sites.

### 6. Other technologies, skills or innovations

- Very high frequency (VHF) radio collars with a mortality switch (Advanced Telemetry Systems), located by triangulation from the ground

- Cage traps baited with scent lures and other attractants, and sedation for collaring

- Standard vegetation tools: a cover board, a canopy densitometer, quadrats, a clinometer, a compass and a 10-factor prism

- Map analyses in ArcGIS Pro using United States Geological Survey elevation and water data

### 7. Implications for conservation (from the paper)

- Bobcats are an economically valuable furbearer and a species of management concern across the United States.

- Den sites with good concealment may improve kitten survival.

- In less rugged landscapes, land management that promotes tree and shrub cover at eye level may provide the cover bobcats need for dens.

### 8. Implications for tracking (Original Wisdom's observations)

_These are Original Wisdom's observations, not the authors'._

The dens in this study were found by radio telemetry and then by approaching the female, which often made her flee. Kitten tracks, scat and prey remains around rock crevices and thickets could be a less disruptive way to find or confirm dens, and they could also show how long a den is used.

## Cite this summary

Lawrence, K. 2026. Summary of: Resource selection of den sites for bobcats (Lynx rufus) in the Northern Great Plains, United States (Morrison and Lehman et al., 2025). Original Wisdom, Tracking Literature. https://www.originalwisdom.com/tracking-literature/2025-morrison-lehman-resource-selection-den-sites/