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Most examples of woodpeckers preying on vertebrates are thought to be opportunistic, and the wider role that some woodpeckers play as nest predators of other birds has not been appreciated until recently. To date, predation on nestling birds has been documented in at least 10 woodpecker species, including 5 of the 6 species of Melanerpes that nest in the United States. From 2018 to 2020, we documented 57 instances in which adult Lewis's Woodpeckers (Melanerpes lewis) provisioned young with nestling passerines (11.9% of 480 food deliveries), which constitutes the first verification of nest predation in this species. Among picids, nest predation is considered to be a widespread and typical foraging strategy only in the Red-bellied Woodpecker (M. carolinus) and Great Spotted Woodpecker (Dendrocopos major). We suggest that additional research will reveal that other woodpecker species routinely prey on nestling birds. [ABSTRACT FROM AUTHOR]

Mountain pine beetle (Dendroctonus ponderosae) outbreaks in western North American coniferous forests are increasing in size and severity. An understanding of wildlife population responses to pine beetle outbreaks is needed to inform habitat conservation strategies. We monitored 355 nests of 5 woodpecker species during 2 sampling periods, before (2003–2006) and after (2009–2014) the peak of a pine beetle outbreak in dry mixed conifer forest of Montana, USA. Three of 5 woodpecker species represented the beetle‐foraging group: American three‐toed (Picoides dorsalis), hairy (Dryobates villosus), and downy (D. pubescens) woodpeckers. The other 2 species studied were northern flicker (Colaptes auratus), a foraging and habitat generalist, and red‐naped sapsucker (Sphyrapicus nuchalis), a sap forager and bark‐gleaning insectivore. We analyzed daily survival rate of nests in relation to pine beetle outbreak (445,000 ha) severity and timing, along with covariates unrelated to the outbreak (temp, nest height, and nest tree diameter). Our results provided stronger evidence for relationships between woodpecker nest survival and the non‐outbreak variables than those associated with outbreaks. Our results indicated limited support for nest survival relationships with beetle severity (annual and cumulative pine tree mortality at 0.81‐ha and 314‐ha scales). Nevertheless, we observed a significant increase in densities of hatched nests for beetle‐foraging woodpeckers following the outbreak. Our results suggest that woodpeckers, particularly beetle foragers, respond numerically to pine beetle outbreaks through increased nesting densities more so than functionally via nest survival. © 2019 The Authors. Journal of Wildlife Management Published by Wiley Periodicals, Inc. on behalf of The Wildlife Society. We analyzed daily survival rate of woodpecker nests in relation to pine beetle outbreak severity and timing, along with covariates unrelated to the outbreak (temp, nest height, and nest tree diameter). Our results provided stronger evidence for relationships between woodpecker nest survival and the non‐outbreak variables than those associated with outbreaks. Woodpeckers in our study, particularly beetle foragers, responded numerically to the pine beetle outbreak through increased nesting densities more so than functionally via nest survival. [ABSTRACT FROM AUTHOR]

• Snags after bark beetle epidemics provide habitat for woodpeckers. • We analyzed snag persistence patterns after bark beetle epidemic in Montana. • Larger, younger, and broken-top snags persisted more than other snags. • Snags in rugged, densely forested plots also persisted longer than other snags. • These patterns help identify snags likely to provide extended habitat value. Bark beetle (Dendroctonus spp.) epidemics generate snags, providing nesting and foraging opportunities for woodpeckers and other disturbance-associated wildlife. Forest managers need to know how long snags persist to include wildlife habitat conservation in their objectives, but published studies of snag persistence following disturbance under-represent beetle-killed forest. We analyzed snag persistence rates in relation to environmental covariates following a mountain pine beetle (Dendroctonus ponderosae) epidemic in the Elkhorn Mountains (Montana, U.S.A.) over a 6-year study period (2010–2015). We evaluated hypothesized relationships with topography, local tree density, and snag characteristics. Consistent with our hypotheses, we found snags with greater diameter at breast height (DBH), younger snags, and broken-top snags persisted relatively long. Also consistent with our hypotheses, snags located in areas of relatively rugged topography and greater tree densities persisted longer. Moreover, we estimated a diameter-height ratio ≥ 4.8 cm × m−1 as a useful threshold for distinguishing broken-top snags likely to persist longer than other snags. Greater snag persistence on north-facing slopes and on topographic high points were inconsistent with our hypotheses, suggesting these conditions may be less useful for understanding snag dynamics. Our study contributes to general knowledge capable of helping managers identify snags most likely to persist and thereby provide extended habitat value for nesting woodpeckers. [ABSTRACT FROM AUTHOR]

Recent epidemics of mountain pine beetles (Dendroctonus ponderosae) have fundamentally altered forests of the Intermountain West, impacting management decisions related to fire, logging, and wildlife conservation. We evaluated how a recent mountain pine beetle epidemic influenced the site occupancy of 39 avian species in forests dominated by ponderosa pine (Pinus ponderosa) on the Helena National Forest, Montana. Point count data were collected during the avian breeding seasons (May–July) of 2003–2006 (pre‐epidemic) and 2009–2011 (during‐epidemic). We used a community‐level Bayesian hierarchical model accounting for imperfect detection to obtain occupancy estimates for all detected forest birds. Our model for site occupancy included the annual presence of mountain pine beetles, the proportion of ponderosa pine at sites, the interaction between the two, and a random effect of year. We observed changes in occurrence over the study period for 23 of 39 species, including shifts toward and away from beetle‐killed ponderosa pine. Community turnover increased during the epidemic and then returned quickly to pre‐epidemic levels. Our results illustrate the myriad habitat preferences of the small landbird community and suggest that a mosaic of disturbed conifer, intact live conifer, and adjacent aspen forests will be critical for the persistence of populations of native avifauna in the Intermountain West. [ABSTRACT FROM AUTHOR]