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
    Author(s): Pam Krannitz Kym Welstead
    Date: 2005
    Source: In: Ralph, C. John; Rich, Terrell D., editors 2005. Bird Conservation Implementation and Integration in the Americas: Proceedings of the Third International Partners in Flight Conference. 2002 March 20-24; Asilomar, California, Volume 1 Gen. Tech. Rep. PSW-GTR-191. Albany, CA: U.S. Dept. of Agriculture, Forest Service, Pacific Southwest Research Station: p. 630-636
    Publication Series: General Technical Report (GTR)
    Station: Pacific Southwest Research Station
    PDF: View PDF  (155 KB)

    Description

    Predation is the predominant cause of nest failure for the Brewer's Sparrow (Spizella breweri breweri), a provincially red-listed shrub-steppe species that has experienced significant declines throughout most of its range. We monitored Brewer’s Sparrow nests and conducted an artificial nest experiment, in the South Okanagan Valley, British Columbia (B.C.), to investigate factors associated with nest predation. Avian predation of artificial nests was higher when nests were placed in smaller shrubs, set out earlier in the season and when corvid numbers were high. Predator imprints on clay eggs in the artificial nest experiment showed that rodent predation increased through the season. Results from real nests indicate that nest initiation date was also an important predictor of nesting success with more predation by all predators later in the season. Nesting density was lower at sites with more corvids, and much higher at similar sites with low corvid numbers. Our results suggest that Brewer's Sparrows select sites lower in avian nest predator activity and that this results in the effect of other predators such as rodent becoming more apparent.

    Publication Notes

    • You may send email to psw_communications@fs.fed.us to request a hard copy of this publication.
    • (Please specify exactly which publication you are requesting and your mailing address.)
    • 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.

    Citation

    Kym Welstead, Pam Krannitz, Nancy Mahony. 2005. Using survival analysis of artificial and Real Brewer''s sparrow (Spizella breweri breweri) nests to model site level and nest site factors associated with nest success in the South Okanagan region of Canada. In: Ralph, C. John; Rich, Terrell D., editors 2005. Bird Conservation Implementation and Integration in the Americas: Proceedings of the Third International Partners in Flight Conference. 2002 March 20-24; Asilomar, California, Volume 1 Gen. Tech. Rep. PSW-GTR-191. Albany, CA: U.S. Dept. of Agriculture, Forest Service, Pacific Southwest Research Station: p. 630-636

    Keywords

    artificial nests, Brewer's Sparrow, corvids, depredation, predator avoidance, Spizella breweri breweri, survival analysis, timing

    Related Search


    XML: View XML
Show More
Show Fewer
Jump to Top of Page
https://www.fs.usda.gov/treesearch/pubs/32015