Relationships between nightly warbler and sparrow nocturnal flight call (NFC) detections and average regional nightly atmospheric or ambient noise conditions estimated via generalized additive models.

aInput variables were centered and scaled; thus, exponentiation of parameter estimates provides the average change in NFC detections per standard deviation change of the input variable. Standard deviations of input variables: wind profit (1.91 m/s), wind speed (1.53 m/s), rain (22.57%), cloud cover (35.27%), visibility (1.70 mi), noise (8.28 dB).b603 residual degrees of freedom.cAlthough the expected associations are one-directional, we report P from the two-sided test to avoid missing large differences in the unexpected direction [72].