Abstract
Smoke from wildfires can be transported hundreds of miles, exposing birds to toxic air across a large geographic area. Yet, research on the impacts of wildfire smoke on wild birds is extremely limited. Quantifying the relationship between wildfire smoke and bird detectability during monitoring surveys is a critical first step in assessing the broader ecological impacts of smoke disturbance. In this study, we evaluate how fine particulate matter (PM 2.5 ), a well-established marker of wildfire smoke and an important air pollutant for public health, influences the probability of observing 84 breeding birds in New York, USA, during the 2021–2023 breeding seasons. We use generalized linear mixed models to relate bird observations from 98,960 eBird checklists to local measurements of ambient PM 2.5 available from ground-based monitors After accounting for habitat, time of day, weather, seasonality, and survey effort, we found that PM 2.5 affected the probability of observing nearly 70% of study species. Across all study species, 18% (15 species) were more likely to be observed and 48% (40 species) were less likely to be observed as PM 2.5 increased. Our findings demonstrate that wildfire smoke influences the probability of observing birds, with species showing divergent responses that may reflect behavioral changes under smoky conditions. Our results support previous research suggesting that wildfire smoke is an important and underexplored component of the detection process; as such, failing to account for air quality may bias models of species distributions and abundance. As climate change continues to escalate global wildfire activity, it is crucial to understand how birds will be affected by increased smoke pollution. Our study provides insights into variation in species responses to smoke exposure, helping inform future research and conservation actions.