Survey wind gave no clear change in prior ozone slopes for US bird richness in four samples in 1995-2024

We tested whether survey-start wind changed the association between prior-season ozone and recorded bird species richness. Four East and West, early and late models used 24,587 accepted US Breeding Bird Survey records in 1995-2024. Models controlled route-observer groups, regional annual changes, weather and survey conditions. Slope changes for Beaufort codes 2-3 versus 0-1 were +0.08, -0.06, -0.85 and -0.54 species per 10 ppb ozone. All four corrected intervals included zero. Four sensitivity checks gave the same uncertain conclusion. Thus, a clear common change did not repeat. This does not show that detection bias is absent or estimate a causal pollution effect. Selected routes, monitor error, coarse weather, start-only wind and few western state clusters limit inference. The package includes data, source hashes, code, numerical checks and a figure.

birds · ozone · wind · observation bias · species richness · regional replication · null result