Nest Box Use by the Dark-eyed Junco (Junco hyemalis)

摘要

The Dark-eyed Junco (Junco hyemalis) is one of the most abundant birds in North America and exhibits versatility in its selection of nest sites. Although typically ground-nesting birds, juncos also nest occasionally in trees, on buildings, and in natural recesses such as rock crevices. To our knowledge, juncos have never been reported nesting in a fully enclosed nest box specifically provided for songbirds. We report the first record of nest box adoption by Dark-eyed Juncos, supported by photographic evidence. A nest box containing a nest attended by a pair of Dark-eyed Juncos was monitored in 2016 in western Washington, USA, and reported to the Cornell Lab of Ornithology's NestWatch program, a national citizen-science program wherein volunteers submit data on wild nesting birds. The nest in question hatched successfully, and three nestlings fledged from the box. Cavity nesting in New World sparrows appears to be very rare, and we found only four additional observations of juncos utilizing natural cavity nests (i.e., a tree hole). Engaging the public to monitor large numbers of nests is the most likely approach to documenting novel nest sites, and citizen science provides the infrastructure for individuals to share observations.