Passive acoustic monitoring reveals the limited distribution of an indicator species, the White-headed Woodpecker (Leuconotopicus albolarvatus), in the northern Blue Mountains, USA

Abstract

Indicator species can facilitate the assessment, management, and conservation of biodiversity. The White-headed Woodpecker (Leuconotopicus albolarvatus) is a species of conservation concern that is considered an indicator species for mature ponderosa pine ecosystems, a priority restoration habitat that has declined by 90% in the northern Blue Mountains, USA. Here, we employed passive acoustic monitoring at 227 randomly selected locations across two National Forests in the northern Blue Mountains. Autonomous recording units were deployed for an average of 4.41 weeks per station (SD = 1.21) and audio recordings were processed with BirdNETv2.4. White-headed Woodpecker predictions were manually reviewed to create detection/non-detection data. We estimated occupancy and detection probabilities using a Bayesian occupancy model and compared the habitat suitability between occupied and unoccupied sites. Naïve occupancy was 7.5%, and the estimated proportion of sites occupied was 0.08 (95% Credible Interval: 0.075, 0.092). The average weekly detection probability was 0.71 (0.60, 0.80), indicating we detected the species with little error when present. Following model selection, we found the odds of occupancy were 5.26 times lower for every 2.87 m²/ha increase in lodgepole pine basal area. Sites considered occupied were also found to have higher values of a habitat suitability metric currently used to inform land management decisions. Low occupancy of White-headed Woodpeckers potentially indicates the northern Blue Mountains cannot currently support a broad distribution of an indicator species for mature ponderosa pine forests. More broadly, this study provides insight into the condition of a regional, priority restoration habitat and provides important information for forest management.

Citation

Ferris, Adrianna J.; Duarte, Adam; Ratliff, Jamie; Vernasco, Ben J. 2026. Passive acoustic monitoring reveals the limited distribution of an indicator species, the White-headed Woodpecker (Leuconotopicus albolarvatus), in the northern Blue Mountains, USA. Journal of Field Ornithology 97(1):3. https://doi.org/10.5751/JFO-00736-970103.