Sora (porzana carolina) parasitism of red-winged blackbird (agelaius phoeniceus) nests

Abstract

Sora (Porzana carolina) is a conspecific brood parasite that also occasionally parasitizes nests of other species. Sora parasitism in nests of passerines is rare. Of 129 Red-winged Blackbird (Agelaius phoeniceus) nests found in North Dakota in 2009 and 2010, two (1.6%) were parasitized by Soras. The conditions favouring this rare parasitic behaviour may include competition for nest sites and high Sora density.