Bark Beetle‐Affected Forests Provide Elk Only a Marginal Refuge from Hunters

Abstract

For nearly 2 decades, the forests of the Rocky Mountains in the United States experienced a bark‐beetle (Dendoctronus ponderosae) epidemic. The number of dead and falling trees from this epidemic likely will affect how elk (Cervus canadensis) and hunters use the forest and their interactions. Downed trees potentially create a component of refuge habitat that could affect the effectiveness of hunting to regulate abundance of growing elk populations. We evaluated how forests affected by bark beetles in south‐central Wyoming, USA, influenced resource selection of 50 female elk and 374 hunters in 2012–2016, and interactions between elk and hunters. We employed global positioning system (GPS) technology on elk and hunters, and developed a satellite‐derived land classification specifically depicting beetle‐affected forests. We tested the predictions that elk would increase use of beetle‐killed areas from summer to the hunting season, and that hunters would avoid beetle‐killed areas regardless of elk use. Elk increased use of beetle‐killed areas during hunting seasons as did hunters during the archery season; however, during the rifle season, hunters avoided beetle‐killed areas. Nevertheless, during the rifle season, areas of beetle‐kill with a high probability of elk occurrence dampened the aversion hunters had towards beetle‐killed areas. Therefore, in contrast to our expectations, forests that have been altered by the bark‐beetle epidemic may only function marginally as a refuge for elk. Our study area was at the beginning of the tree‐fall phase (i.e., ~3–7 yr after peak infestation) of the bark‐beetle epidemic; thus, future research efforts should focus on how a continued increase in downed trees will influence interactions between elk and hunters. At current levels of tree fall, however, beetle‐kill should not limit the ability of managers to regulate elk herds through harvest. © 2020 The Wildlife Society.

Sex‐Specific Behaviors of Hunted Mule Deer During Rifle Season

“…This is consistent with behavior during summer in previous studies on mule deer in arid climates (Hayes and Krausman 1993, Tull et al 2001, Ager et al 2003, Morano et al 2019), where deer are more active in foraging areas at night and select resting areas with moderate canopy cover during the day (other ungulates, Giotto et al 2013, Long et al 2014). During the rifle season, habitat use by males was not related to density of canopy, but males increased distance from motorized routes, suggesting that avoidance of human activity was a priority behavior, as is true during hunting season in other ungulates (white‐tailed deer [ Odocoileus virginianus ], Kilgo et al 1998; roe deer [ Capreolus capreolus ], Bonnot et al 2013; and elk, Proffitt et al 2013, Paton et al 2017, Spitz et al 2019, Lamont et al 2020).…”

“…Moreover, hunting season dates and types (i.e., rifle vs. archery; Proffitt et al 2009, Ranglack et al 2017, hunting modalities (i.e., foot vs. motorized ;Stankowich 2008), and the distribution of land management status can elicit variable behavioral responses in different species. In general, however, studies in western North America (Conner et al 2001;Vieira et al 2003;Proffitt et al 2009Proffitt et al , 2010Proffitt et al , 2013Ranglack et al 2017;DeVoe et al 2019) have reported habitat shifts toward refugia or security areas during hunting season (Mikle et al 2019, Lamont et al 2020. Specifically, disturbance from hunting can cause animals to move to areas farther from roads (Bonnot et al 2013, Paton et al 2017, DeVoe et al 2019, Spitz et al 2019, with higher canopy cover (Ranglack et al 2017), or restricted public access (Proffitt et al 2009(Proffitt et al , 2010Mikle et al 2019).…”

Influence of Landscape Characteristics on Hunter Space Use and Success

“…Hunter Space Use and Roads Models of space use revealed strong links of most Starkey hunters, especially rifle deer hunters, with open roads during shooting hours, a behavior well-documented for elk (Lyon and Burcham 1998, Gratson and Whitman 2000b, Lamont et al 2020) and white-tailed deer (Stedman et al 2004) hunters. In Pennsylvania, nearly 90% of deer hunters remained within 0.5 km of a road (Diefenbach et al 2005).…”

“…We determined that most stationary locations (i.e., consecutive locations in camp) were contained within a 200-m radius of the cluster centroid; thus, we excluded from analysis any telemetry locations within a 200-m radius of hunter camps. We further censored locations to exclude those obtained during the scouting period, outside legal shooting hours plus a 1-hour buffer before and after (Lamont et al 2020), within 300 m of the check station (Gerrits et al 2020), and after the day of harvest (successful hunters only; Plante et al 2017).…”

“…Investigations of hunter movements began in the 1990s (Bryant et al 1991, Stedman et al 2004), and Lyon and Burcham (1998) published the first such study in the United States using global positioning system (GPS) telemetry to track elk ( Cervus canadensis ) hunters in Montana. More recent studies are increasingly sophisticated, describing elk and hunter space‐use sharing (Millspaugh et al 2000), habitat use of recreational hunters (Pauli et al 2019), resource selection of caribou ( Rangifer tarandus ) hunters and their prey (Plante et al 2017), habitat characteristics associated with white‐tailed deer ( Odocoileus virginianus ) harvest (Lebel et al 2012), and effects of beetle‐killed forests on resource selection of elk and hunters (Lamont et al 2020). No studies have related spatially explicit hunter movements to hunt outcome (i.e., successful vs. unsuccessful hunters), however, other than modeling success of white‐tailed deer hunters with categorical spatial data from hunter surveys (Bhandari et al 2006).…”