Do adult eastern bluebird Sialia sialis males recognize juvenile-specific traits?

Alternative Material Nest Boxes and Impacts on Nestling Physiology and Adult Behavior in the Eastern Bluebird (Sialia sialis)

Evidence that plumage bacteria influence feather coloration and body condition of eastern bluebirds Sialia sialis

Parasites influence the expression of secondary sexual traits and the health of infected individuals. We set out to test the influence of reputed exogenous parasites, plumage bacteria, including feather-degrading bacteria (FDB), on secondary sexual characteristics and body condition of wild adult eastern bluebirds Sialia sialis. Previous work has shown that FDB alter the coloration of structura...

Occurrence of twin embryos in the eastern bluebird

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 p...

Increased perception of predation risk to adults and offspring alters avian reproductive strategy and performance

Predation risk can inflict profound effects on prey by influencing prey behavior and other traits. Prey are often subjected to a diversity of predators, which can exert differential predation pressures on prey life-history strategies. In birds, breeding adults and offspring (as eggs, nestlings, and fledglings) are susceptible to different types of predators, and life-history theory predicts tha...

Sex-specific costs of reproduction in Eastern Bluebirds Sialia sialis.

In species with bi-parental care, individuals must partition energy between parental effort and mating effort. Typically, female songbirds invest more than males in reproductive activities such as egg-laying and incubation, but males invest more in secondary sexual traits used in attracting mates. Animals that breed more than once within a season must also allocate time and energy between first...