PASSERINE BREEDING AND POST-FLEDGLING HABITAT USE IN RIPARIAN AND UPLAND TEMPERATE FORESTS OF THE AMERICAN MIDWEST

Riparian forests are thought to be important habitat for fledglings in a diversity of temperate-forest passerines, yet few studies have examined this hypothesis. The main objective of this study, conducted in temperate deciduous forests in Michigan's Lower Peninsula, was to compare bird use of riparian and upland forests during and after breeding. Using mist-nets, we quantified populations in accordance with the Monitoring Avian Productivity and Survivorship (MAPS) protocol. Nets were set up in both riparian and upland forests in a paired sampling design. After fledging, we captured juveniles, including those of the Ovenbird (Seiurus aurocapilla), at a rate higher in riparian than in upland forests. The trend for adult Ovenbirds was similar. For riparian breeders, we found no difference in capture rates over time between upland and riparian forests; these species appeared to stay in riparian forests after fledging. Our results suggest that riparian forests are important habitat for passerines during the period following fledging; they need to be considered accordingly during conservation planning.