Differentiating the Songs of the Green-tailed Towhee and Thick-billed Fox Sparrow

Abstract

Two common Sierra Nevada breeders, the Thick-billed Fox Sparrow and the Green-tailed Towhee, share similar habitats, sing very similar songs, and often sing while hidden in the brush. I analyzed some aspects of their songs, finding two characteristics that may provide a reliable way to distinguish between their songs in the field.