Vegetative Characteristics and Size of Home Ranges Used by Pygmy Rabbits (Brachylagus idahoensis) during Winter

Abstract

We determined sizes of home ranges for pygmy rabbits in southwestern Wyoming and characterized the vegetation within and outside those areas used during winters of 1993 and 1994. Seventy percent of pygmy rabbits used more than one core area within their home range. Habitats within home ranges had less low ground cover and a greater number of wider, taller Artemisia tridentata than did adjacent non-used areas. Pygmy rabbits selectively used dense and structurally diverse stands of A. t. tridentata, which also accumulated more snow than areas of low use. Structure and diversity of vegetation above the snow's surface declined as the season progressed and depths of snow increased. The subnivean environment provided access to a relatively constant supply of food and provided protection from predators and thermal extremes. We suggest that size of home ranges used by pygmy rabbits is influenced more by amount of vegetative cover than by forage.

Fragmentation of sagebrush communities: does an increase in habitat edge impact pygmy rabbits?

“…Alteration and fragmentation of sagebrush could limit the size and stability of pygmy rabbit populations due to potentially low capabilities for dispersal of this species across unsuitable habitat (Katzner & Parker, 1997;Larrucea & Brussard, 2008c). Pygmy rabbits use shrubs for cover and large open spaces may act as a barrier to movement (Weiss & Verts, 1984;Estes-Zumpf & Rachlow, 2009).…”

“…Pygmy rabbits are known to use more than one core area within their home range; however, these leporids spend much of their time within 30-100 m of burrow systems (Katzner & Parker, 1997;Heady & Laundr´e, 2005;Crawford, 2008). Given these small patterns of space use, and to test for a relationship between burrow activity and distance from habitat edge, we calculated the proportion of active burrows in 10 m increments from habitat edge up to 100 m into contiguous sagebrush.…”

“…during winter and 51% during summer (Green & Flinders, 1980b;Gahr, 1993). These rabbits rely on areas of contiguous sagebrush habitat throughout all phases of their life cycle and may be particularly sensitive to fragmentation and alteration of sagebrush communities (Weiss & Verts, 1984;Katzner & Parker, 1997;Thines et al, 2004;Larrucea & Brussard, 2008b,c). Given the scope and scale of change occurring in sagebrush habitats, recent petitions have argued that pygmy rabbits warrant listing under the United States Endangered Species Act because these leporids may be declining across their range.…”

Habitat specialists as conservation umbrellas: Do areas managed for greater sage‐grouse also protect pygmy rabbits?

“…Soil characteristics such as depth, type, and strength that are conducive to burrowing and holding burrow structure for long time periods are known to influence pygmy rabbit occurrence (Weiss and Verts 1984, Katzner and Parker 1997, Heady and Laundr e 2005, Parsons et al 2016). Soil characteristics such as depth, type, and strength that are conducive to burrowing and holding burrow structure for long time periods are known to influence pygmy rabbit occurrence (Weiss and Verts 1984, Katzner and Parker 1997, Heady and Laundr e 2005, Parsons et al 2016).…”

Pygmy Rabbit (Brachylagus idahoensis) Habitat Selection: Does Sagebrush (Artemisiaspp.) Age Influence Selection?

“…Habitat requirements for pygmy rabbits have been described in several western states, including California (Larrucea and Brussard 2008b), Idaho (Green and Flinders 1980), Nevada (Himes andDrohan 2007, Larrucea andBrussard 2008b), Oregon (Weiss and Verts 1984), Washington (Gahr 1993), and Wyoming (Katzner and Parker 1997). However, only limited habitat selection work has been published for pygmy rabbits in Utah, and identification of certain characteristics associated with preferred habitats (i.e., sagebrush age) is lacking (Larrucea andBrussard 2008b, Wilson et al 2010).…”