Pallid Bat – Oregon Conservation Strategy

A pallid bat (Antrozous pallidus) flying at night near Sulphur Springs, high-desert habitat, Washington. Photo Credit: Michael Durham, https://www.flickr.com/photos/oregonwild/

Overview

Species Common Name Pallid Bat
Species Scientific Name Antrozous pallidus
Federal Listing Status Species of Concern
State Listing Status Sensitive

Ecoregions

Blue Mountains

Located in NE Oregon, the Blue Mountains ecoregion is the largest ecoregion in the state. It provides a diverse complex of mountain ranges, valleys, and plateaus that extend beyond Oregon into the states of Idaho and Washington.

Columbia Plateau

The Columbia Plateau ecoregion was shaped by cataclysmic floods and large deposits of wind-borne silt and sand earlier in its geological history. It is dominated by a rolling landscape of arid lowlands dissected by several important rivers, and extends from the eastern slopes of the Cascades Mountains, south and east from the Columbia River to the Blue Mountains.

East Cascades

The East Cascade ecoregion extends from the Cascade Mountains’ summit east to the warmer, drier high desert and down the length of the state. This ecoregion varies dramatically from its cool, moist border with the West Cascades ecoregion to its dry eastern border, where it meets sagebrush desert landscapes.

Klamath Mountains

The Klamath Mountains ecoregion covers much of southwestern Oregon, including the Umpqua Mountains, Siskiyou Mountains, and interior valleys and foothills between these and the Cascade Range. The Rogue watershed has the largest population of any coastal watershed in Oregon (Jackson County, Josephine County, and a portion of Curry County). Several popular and scenic rivers run …

Northern Basin and Range

The Northern Basin and Range ecoregion covers the very large southeastern portion of the state, from Burns south to the Nevada border and from the Christmas Valley east to Idaho. It is largely a high elevation desert-like area dominated by sagebrush communities and habitats.

Special needs

Pallid bats are found in dry, open habitat. They use crevices in cliffs, caves, mines, or bridges (and sometimes, buildings) for day, night, or maternity roosts, or hibernacula. In some areas, they use snags as day roosts. Pallid bats prefer grassland, shrub-steppe, and dry forest ecotones for foraging. They also associate with open-water sites within the landscape.

Limiting factors

Pallid bats are patchily distributed and have low reproductive rates. They are sensitive to disturbance at roosts. Loss of low-elevation, dry ecosystems (native grasslands, shrub-steppe, and open ponderosa pine woodlands) to development, and loss of ponderosa pine snags, may be key limiting factors.

Data gaps

Determine statewide distribution, abundance, and trends. Investigate seasonal movements. Identify maternity and winter roost locations and associated microclimate conditions.

Conservation actions

Use gates and seasonal closures to protect known roost sites during sensitive times (raising young and hibernation). Maintain open-water sources in dry landscapes. Manage rock features, such as cliffs, to avoid conflict with recreational use and rock removal. Complete bridge replacement and maintenance when bats are absent. Maintain large pine snags in shrub-steppe/forest ecotones. Maintain and restore native grassland, shrub-steppe, and open ponderosa pine habitat.

Key reference or plan

ISSSSP Bat Grid Monitoring – Oregon and Washington