Use of Tree Cavities by Nesting Eastern Bluebirds

Nestbox orientation: a species-specific influence on occupation and breeding success in woodland passerines

“…1b-1d). This finding is consistent with studies of other passerines, including Eastern Bluebirds (Pinkowski 1976) and Prothonotary Warblers Protonotaria citrea (Blem & Blem 1991). However, although Great Tits did occupy nestboxes of any orientation, boxes facing south-southwest were occupied 32% less frequently than those facing other directions (Fig.…”

“…Other species select their nest cavity independently of orientation, although orientation affects subsequent breeding success. For example, while Eastern Bluebirds Sialia sialis do not choose nest cavities according to orientation (Pinkowski 1976), individuals nesting in northeast-facing cavities fledge a significantly higher number of young than those using cavities oriented west (Dhondt & Phillips 2001). Conversely, a species may exhibit an orientation preference that is not converted into increased reproductive success.…”

Eastern Bluebirds Choose Nest Boxes Based on Box Orientation

“…Our fi nding that Eastern Bluebirds in Georgia prefer to nest in northwest-facing boxes was surprising given that Eastern Bluebirds in Michigan showed preferences for southeast-facing boxes (Pinkowski 1976). Southeast-facing boxes are also recommended by Eastern Bluebird guides (reviewed in Napper 2005).…”

“…Indeed, Dhondt and Phillips (2001) showed that more nestlings fledged from boxes facing northeast as compared to northwest, southeast, and southwest, in northern populations of Eastern Bluebirds. Pinkowski (1976) showed that significantly more Eastern Bluebirds nested in boxes facing southeast in his Michigan population. For an Ohio population, Napper (2005) also suggested that more birds nested in boxes facing southeast, but this difference was not statistically significant.…”

Variation in offspring quality with cavity orientation in the great tit

“…Thirdly, some species apparently select nest cavities independently of orientation, even though orientation subsequently affects their breeding success. For example, while eastern bluebirds Sialia sialis do not choose nest cavities according to the direction they face (PINKOWSKI 1976), 60 individuals nesting in northeast-facing cavities fledge significantly more young than those using cavities facing west (DHONDT & PHILLIPS 2001). This may occur when nest-site selection is constrained by the availability of natural or previously-excavated cavities.…”