The Scaling of Sound Output and Territory Size: Are They Matched?

Abstract

The size—dependence of sound output power has important implications for ecology, behavioral energetics, and physiology. The sound power of 32 species of birds and the areas occupied by individuals of 86 species of birds show quantitative similarity in scaling to body size. This suggests a general matching of sound output power to dimensions of the spatial requirements of a species. Sound output was ±81.3 mW/ha of territory, and was independent of bird size (6—10 800 g). The allometric patterns tend to confirm conclusions from both theory and studies of single species. Caution should be exercised in estimating population densities from transect censuses than depend heavily on call and song, because of possible size—dependent bias in detectability.