Clark, Robert G., Joseph P. Fleskes, Karla L. Guyn, David A. Haukos, Jane E. Austin, and Michael R. Miller. 2014. “Northern Pintail (Anas acuta).” The Birds of North America, edited by Paul G. Rodewald. Ithaca: Cornell Lab of Ornithology. Retrieved from the Birds of North America: https://birdsna.org/Species-Account/bna/species/norpin doi: 10.2173/bna.163