Wildfire smoke linked to fewer birds in New York ^{CEFR B2}

New research in Biodiversity and Conservation shows a link between smoke from Canadian wildfires and reduced bird sightings across New York during recent breeding seasons. The authors report that PM2.5, or fine particulate matter, reached its highest concentrations in 2023 when smoke degraded air quality across the state throughout June and July, and at times exceeded World Health Organization guidelines by large margins.

The study examined PM2.5 across New York for the 2021–2023 breeding seasons and matched those measurements with nearly 99,000 birdwatching checklists submitted to Cornell University's eBird database. After rigorous data filtering and statistical controls, the researchers analysed 84 species and found that 40 species were less likely to be observed as PM2.5 increased, 15 species were more likely, and 29 showed no significant change. Many of the species with declines were migratory forest songbirds, including warblers, thrushes and vireos.

Lead author Festus Adegbola said smoky conditions may alter bird behaviour or make individuals harder to detect. Coauthor Adam Wilson added that higher sightings for some species might reflect where observers chose to go during smoky conditions rather than a true benefit. The team emphasises the need to separate reduced detectability from real population declines and calls for further study of smoke impacts as climate change intensifies wildfires. Other coauthors are from the University at Buffalo and the Cornell Lab of Ornithology.