Occurrence of Polygyny and Double Brooding In the Eastern Wood-Pewee

Abstract

Abstract We document the first confirmed cases of polygyny and double brooding in the Eastern Wood-Pewee (Contopus virens). During an intensive study of the effects of shelterwood harvesting on canopy-nesting songbirds in southeastern Ohio, 2007–2010, we color-banded 79 Eastern Wood-Pewees and monitored 237 pewee nests. In 2007, we confirmed a color-banded male provisioning at two concurrently active nests; the male was polygynous in at least two consecutive years. In 2009, we observed an unbanded female feeding fledglings and subsequently shaping a nest from which young had recently fledged; the female successfully fledged two broods from the same nest. In addition to confirmed observations, we identified several other probable cases of polygyny and double brooding. In our upland oak system, we estimated rates of polygyny from 6–22% with the greatest occurrence of polygyny during a dry spring in 2007; rates of double brooding may have been as high as 6–12%. Males appeared to benefit from polygyny, becaus...