Brood parasitism of greater sage-grouse by California Quail in Idaho

We describe a case of brood parasitism of a Greater Sage-Grouse (Centrocercus urophasianus; hereafter, sage-grouse) nest by California Quail (Callipepla californica; hereafter, quail) in southwestern Idaho during 2019. We observed one quail egg in the parasitized nest; the egg partially hatched, but the chick was dead upon the final nest check. Of the 6 sage-grouse eggs in the nest, only 2 hatched, although the eggs contained chicks that appeared nearly completely developed. Identification of the quail chick was confirmed using mitochondrial DNA. Additional monitoring and documentation of this behavioral interaction is warranted to better understand its prevalence and any reproductive consequences for sage-grouse.