Feeding behavior of nestling Eastern Bluebirds (Sialia sialis) in east-central Illinois

Abstract

I observed feeding of nestlings in Eastern Bluebirds
in nest boxes in east-central Illinois. Provisioning rate
of males and females were compared and early observation
periods (younger nestlings) were compared with late
observation periods (older nestlings). I also compared the
average food size brought to the nestlings by males and
females and during early and late observations. No
significant differences were found between average food
sizes throughout the study. In addition, food size was not
significantly correlated with mean nestling weights within
a brood. However, males had significantly fewer confirmed
feedings than females for the last observation period. In
addition, there was a significant increase in female's
confirmed feedings from the first observation period to the
last, whereas the overall number of nest visits by males
decreased significantly from the first observation period.
I found no significant correlation between either total
visitation rates or confirmed feeding rates and mean
nestling weights within a brood. Finally, parents of
broods with high weight variation (sometimes created by
artificially increasing hatching spans) did not appear to
increase the size variation of the foods they brought to
the nest.

Date of Award	2012
Original language	American English
Awarding Institution	Eastern Illinois University
Supervisor	Eric K. Bollinger (Supervisor)