Three eight…thirty-eight… (Pielow 2017)
Lower pitched and more buzzy than red-eyed and blue-headed vireo (Pielow 2017)
Full second between phrases (Rodewald and James 2020)
Pieplow, Nathan (2017). Peterson Field Guide to Bird Sounds of Eastern North America. Houghton Mifflin Harcourt, Boston, MA.
Rodewald, P. G. and R. D. James (2020). Yellow-throated Vireo (Vireo flavifrons), version 1.0. In Birds of the World (A. F. Poole, Editor). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bow.yetvir.01