Foraging-substrate use by house wrens nesting in natural cavities in a riparian habitat

Abstract

Foraging behaviour and substrate use by the primarily insectivorous house wren (Troglodytes aedon) were studied during the 1982 breeding season at 10 natural nesting sites in the dune-ridge forest, Delta Marsh, Manitoba. The foraging variables, i.e., time of season, gender, nesting stage, nest site, and time of day, interacted significantly. Wrens gleaned prey off substrate in 82.5% of the prey captures observed. Foraging behaviour varied greatly among the nest sites studied because of prevailing local differences in habitat, and possibly prey availability. The plant species from which wrens gleaned their prey correlated closely with the availability of the substrates in the habitat surrounding each nest site.