Distribution and habitat selection of the pygmy rabbit, Brachylagus idahoensis, in Nevada (USA)

Abstract

We surveyed for pygmy rabbits, Brachylagus idahoensis, in Summer 2003 in Nevada (USA) to better determine the distribution, habitat, and soil patterns of this potentially threatened species. Pygmy rabbits and/or their sign (burrows and fecal pellets) were observed at 261 of 643 survey sites and their known distribution was extended 12 km to the south. Data on topography, soil, lithology, and hydrology were compared between sagebrush habitats where pygmy rabbits and/or their sign was present and absent. A predictive equation was produced and used as a model for characterizing habitats where pygmy rabbits were present. This model successfully explained the occurrence of pygmy rabbits and/or their sign on 56.7% of the surveyed transects. Sites occupied by pygmy rabbits were closer to perennial streams, had deeper soils, and had more northerly aspects than did unoccupied sites. Burrows and pellets were excellent indicators of the occurrence of pygmy rabbits, and thus should be considered indicators of the presence of rabbits when conducting surveys in similar ecosystems due to the difficulty of observing rabbits in tall, dense stands of sagebrush where they are most common. The results of this survey indicate that pygmy rabbits are not as uncommon in Nevada as previously thought.