We studied the nest-site characteristics of Western Bluebirds nesting in natural tree cavities in burned and unburned logged ponderosa pine forests along the east-slope of the Cascade Range of Washington, 2003–2008 and 2010. We compared 13 bluebird nest-site habitat variables between burned and unburned stands by assessing overlap in 95% CI.
Evaluating rates of nestling provisioning by adult birds provides insight into foraging strategies and reproductive effort. In most biparental avian species, both males and females provision the young, although this task is not always shared equally between sexes. In woodpeckers (Picidae), biparental care is thought to be necessary to successfully raise offspring, resulting in social monogamy for most woodpecker species. Unlike other avian groups, such as passerines, where females generally invest more than males in raising offspring, male woodpeckers contribute significantly to raising you
Interior ponderosa pine (Pinus ponderosa) forests of the Pacific Northwest have changed dramatically since the time of European settlement. As a result of decades of fire suppression and timber management that focused on selective removal of large-diameter trees, ponderosa pine forests today have high densities of small diameter trees and low densities of large diameter trees and snags, as well as an encroachment of shade tolerant tree species.
The White-headed Woodpecker (Dryobates albolarvatus) is a primary excavator that occurs in pine- (Pinus spp.) dominated habitats throughout its geographic distribution. Throughout the interior Pacific Northwest, the White-headed Woodpecker is historically associated with large-diameter ponderosa pine (Pinus ponderosa) forests. Historically these pine forests were maintained by frequent fires that occurred every 5–15 years. Old trees (>150 years) in these historic forests were 40–91 cm dbh and ranged in density from 19 to 49 per hectare.
The Western Bluebird (Sialia mexicana) is a secondary-cavity-nesting thrush that breeds in semi-open habitats throughout much of western North America. Historically, the Western Bluebird was more common in Washington west of the Cascade crest than to the east, but today it is more abundant in the eastern Cascades.
Woodpeckers are considered keystone species because of their broad effects on other species. In nesting and foraging, woodpeckers create cavities and excavations that other species use, they aid in controlling forest insects, and they may help in dispersing spores of fungi that are agents of decay. Despite the importance of woodpeckers to forested ecosystems, few studies have examined metrics of woodpecker demography such as reproductive success or nest survival or have investigated the associations of habitat characteristics with these or related metrics.