Skip to Main Content
U.S. Forest Service
Caring for the land and serving people

United States Department of Agriculture

Home > Search > Publication Information

  1. Share via EmailShare on FacebookShare on LinkedInShare on Twitter
    Dislike this pubLike this pub


    For birds, risk of nest predation can vary within a breeding season, but few data exist that explain why such variation occurs. We investigated intraseasonal variation of nest survival of the Acadian Flycatcher (Empidonax virescens) in Midwestern forests and tested whether four of the adults' reproductive strategies (clutch size, nest concealment, nest visitation rates, nest height) explained trends in survival across the breeding season. We also used video cameras to identify predators at 40 nests, which allowed us to determine whether variation in predation rates by category of predator (e.g., birds, mammals, snakes) explained overall seasonal variation in predation rates. The flycatchers' nest survival had a quadratic relationship with Julian date but generally increased through the breeding season. Nest height increased as the breeding season progressed but did not explain any variation in nest survival. No other reproductive trait exhibited significant intraseasonal variation. Overall, predator-specific predation rates did not vary seasonally, but there was a marginal decline in the risk of failure from avian predators as the season progressed. Of the explanations we considered, changes in predator abundance or activity were likely the primary contributor to intraseasonal variation in survival of Acadian Flycatcher nests.

    Publication Notes

    • Check the Northern Research Station web site to request a printed copy of this publication.
    • Our on-line publications are scanned and captured using Adobe Acrobat.
    • During the capture process some typographical errors may occur.
    • Please contact Sharon Hobrla, if you notice any errors which make this publication unusable.
    • We recommend that you also print this page and attach it to the printout of the article, to retain the full citation information.
    • This article was written and prepared by U.S. Government employees on official time, and is therefore in the public domain.


    Hirsch-Jacobson, Robin; Cox, W. Andrew; Tewes, Emily E.; Thompson, Frank R., III; Faaborg, John. 2012. Parents or predators: Examining intraseasonal variation in nest survival for migratory passerine. The Condor. 114(2): 358-364.


    Acadian Flycatcher, Empidonax virescens, nest survival, nest-visitation rates, reproductive strategies, seasonality

    Related Search

    XML: View XML
Show More
Show Fewer
Jump to Top of Page