Garcia-Perez, Belen; Hobson, Keith A.; Powell, Rebecca L.; Still, Christopher J.; Huber, Gernot H. (Public Library of Science, 2013-01-31)
Background: Barn Swallows (Hirundo rustica) breed almost exclusively in the Northern Hemisphere. However, since the early 1980's, a small disjunct breeding population has become established in eastern Argentina, presumab ...