The aim of this study was to provide optimal methodological criteria for the quantitative and qualitative estimates of bird communities inhabiting woodland areas using point counts. Results obtained from counts carried out once or twice during the same breeding season were compared and the optimal duration of each session was assessed. Data obtained in three different woodland areas, from a total of 46 point counts each lasting 20 min. and repeated twice in the breeding season were analyzed in 5-min. blocks. It was concluded that 10-min. sessions repeated twice in a breeding season can provide a good description of the passerine bird community. However, some rarer species of the breeding community under study, including some diurnal raptors, woodpeckers, and scarce passerines, could be underestimated with this duration.
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1 December 2000
Assessing Bird Communities by Point Counts: Repeated Sessions and their Duration
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Acta Ornithologica
Vol. 35 • No. 2
December 2000
Vol. 35 • No. 2
December 2000
bird census
Breeding season
point count duration