Meeting Abstract

P3.111  Thursday, Jan. 6  Nest box orientation and surrounding vegetation height influence nest box preference in eastern bluebirds ANDERSON, EM*; NAVARA, KJ; The University of Georiga; The University of Georgia knavara@uga.edu

As a response to substantial declines in populations of eastern bluebirds, there has been a large movement throughout North America to construct and place man-made nest boxes to stimulate bluebird nesting. While large-scale habitat preferences of nesting bluebirds have been well-established, the precise factors that influence nest box preference within habitats that are relatively homogeneous remain unclear. Factors that affect foraging efficiency, developmental stability of offspring, and predation risk are likely most influential in decisions about nest box preference. We tested the effects of (1) nest box orientation, which could substantially influence the microhabitat in which offspring are developing, (2) vegetation height, an effector of foraging efficiency and predator exposure, and (3) the level of human disturbance on nest box occupancy. The level of human disturbance did not affect nest box preference; however, both box orientation and the presence of surrounding vegetation influenced box occupancy. Bluebirds preferred to nest in boxes that faced northwest and that were surrounded by little or no vegetation. Our findings differ from previous studies conducted on bluebirds at northern latitudes, in which southeast-facing boxes were preferred, suggesting the potential for latitudinal variation in preference for nest box characteristics.