In terms of nature conservation monitoring of animal populations is of great importance. For birds several standardized methods exist to estimate population sizes by mapping singing males within their territories during the breeding season. In most woodpecker species these surveys are done by mapping drumming males that in some cases are hard to localize by an observer especially if the population density is high and several individuals of different species are drumming simultaneously. The idea of the study was to design and test a feasible microphone setup that takes on the principle of the established methods and enables to conduct surveys by locating drumming signals via acoustic recordings. Four-channel-recordings with cardioid microphones in cross configuration were conducted within a woodpecker community in a natural preserve north of Berlin. Territories were estimated by mapping the localization results of drumming signals obtained by triangulation using cross correlation techniques and additional distance information from sound pressure measurements. The findings showed good correlations with the onsite mapping of drumming individuals by an ornithologist concerning the species composition as well as the individuals’ territories situation.
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