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The White-headed Woodpecker is currently placed in the genus Picoides, a genus poorly understood phylogenetically and subject to frequent revisions over the years (Garrett et al. 1996). Eight other Picoides species occur in North America: Ladderbacked (P. scalaris), Red-cockaded (P. borealis), Nuttall's (P. nuttallii), Strickland's (P. stricklandi), Downy (P. pubescens), Hairy (P. villosus), Three-toed (P. tridactylus), and Black-backed (P. arcticus) woodpeckers (AOU 1998). Two subspecies of White-headed Woodpecker are recognized: one occurring in the mountains of southern California (P. albolarvatus gravirostris), and the other from British Columbia to the Sierra Nevada in central California (P. albolarvatus albolarvatus) (Garrett et al. 1996; Cannings 1998). Description The White-headed Woodpecker is unique among North American woodpeckers in having entirely black body plumage and tail, with only the face, throat, crown, and large patch at the base of the primaries white. Males have a red patch at the back of the head; juvenile males have a variable patch of red on the crown (Garrett et al. 1996; NGS 1999). Clark's Nutcracker (Nucifruga columbiana), a corvid with pale grey head, and woodpecker-like bill and behaviour, is occasionally mistaken for the Whiteheaded Woodpecker (Cannings 2000). Distribution Global The White-headed Woodpecker is restricted to western North America, ranging from extreme southcentral British Columbia southward, primarily east of the Cascades, to southern California (Garrett et al. 1996). British Columbia The White-headed Woodpecker is a very rare resident in the Okanagan Valley from Naramata south, and occasionally resides in the Similkameen Valley, Grand Forks area, and the Kootenays (Weber and Cannings 1976; Cannings et al. 1987; Campbell et al. 1988; Campbell et al. 1990). Sightings in suitable habitat have also been reported from Lytton, Manning Park, Bummers Flats north of Cranbrook, and south of Golden but have not been substantiated by detailed descriptions or photos (Weber and Cannings 1976; Campbell et al. 1990).

Efforts to conserve bats in the western United States have long been impeded by a lack of information on their winter whereabouts, particularly bats in the genus Myotis. The recent arrival of white-nose syndrome in western North America has increased the urgency to characterize winter roost habitats in this region. We compiled 4,549 winter bat survey records from 2,888 unique structures across 11 western states. Myotis bats were reported from 18.5% of structures with 95% of aggregations composed of ≤10 individuals. Only 11 structures contained ≥100 Myotis individuals and 6 contained ≥500 individuals. Townsend’s big-eared bat (Corynorhinus townsendii) were reported from 38% of structures, with 72% of aggregations composed of ≤10 individuals. Aggregations of ≥100 Townsend’s big-eared bats were observed at 41 different caves or mines across 9 states. We used zero-inflated negative binomial regression to explore biogeographic patterns of winter roost counts. Myotis counts were greater in caves than mines, in more recent years, and in more easterly longitudes, northerly latitudes, higher elevations, and in areas with higher surface temperatures and lower precipitation. Townsend’s big-eared bat counts were greater in caves, during more recent years, and in more westerly longitudes. Karst topography was associated with higher Townsend’s big-eared bat counts but did not appear to influence Myotis counts. We found stable or slightly-increasing trends over time in counts for both Myotis and Townsend’s big-eared bats from 82 hibernacula surveyed ≥5 winters since 1990. Highly-dispersed winter roosting of Myotis in the western USA complicates efforts to monitor population trends and impacts of disease. However, our results reveal opportunities to monitor winter population status of Townsend’s big-eared bats across this region.

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