The influence of weather conditions on the detection of birds during Common Birds Census fieldwork

Publisher Website
Google Scholar
Abstract
The results from a series of 40 Common Birds Census visits to a census plot on Aston Rowant NNR, Buckinghamshire [Britain, UK], were examined in relation to the weather on the day of the census. For most species, the number of census registrations obtained was dependent on at least 1 weather factor: on temperature (8 spp.), wind strength (4 spp.), rainfall (2 spp.), and cloud cover (2 spp.). Only wren and goldcrest registrations were significantly affected by > 1 weather factor. The results showed significant bias towards more frequent registrations on warm days and on dry days. Individual species less frequently detected on windy days were those with weak voices or that sing from treetops. Among the early-breeding species the sensitivity of registration frequency to temperature was dependent on species body size. The weather influences detected were too weak to bias CBC results, though confirming the inadequacy of results gathered on very cold or on very wet days.