Occurrence of twin embryos in the eastern bluebird

Citizen Science, Cornell Lab of Ornithology, Ithaca, NY, United States
Retired, State College, PA, United States
DOI
10.7287/peerj.preprints.186v2
Subject Areas
Ecology, Zoology
Keywords
eastern bluebird, Pennsylvania, Sialia sialis, twinning, double-yolked egg, citizen science
Copyright
© 2014 Bailey et al.
Licence
This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Cite this article
Bailey RL, Clark GE. 2014. Occurrence of twin embryos in the eastern bluebird. PeerJ PrePrints 2:e186v2

Abstract

We report the first record of presumed twinning in eastern bluebird (Sialia sialis) and provide a review of previously reported twinning events in wild birds. A nest containing twin eastern bluebird nestlings was monitored in 2013 in central Pennsylvania and reported to the Cornell Lab of Ornithology’s NestWatch program, a national program where volunteers submit data on wild nesting birds. A presumed double-yolked egg of a free-living eastern bluebird pair hatched successfully, and twin nestlings lived for 11 days in a nest box shared by three siblings. Due to the rarity of twinning in wild birds, engaging the public to monitor large numbers of nests is the most likely approach to documenting twinning in wild populations, and citizen science provides the infrastructure for individuals to share observations.

Author Comment

Version 2 is the peer-reviewed version now published on PeerJ.

Supplemental Information

Table S1

Nest visits (extracted from NestWatch.org) documenting the chronology of an Eastern Bluebird nest attempt containing twin embryos.

DOI: 10.7287/peerj.preprints.186v2/supp-1