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): David G. Ainley; Sarah G. Allen; Larry B. Spear
    Date: 1995
    Source: In: Ralph, C. John; Hunt, George L., Jr.; Raphael, Martin G.; Piatt, John F., Technical Editors. 1995. Ecology and conservation of the Marbled Murrelet. Gen. Tech. Rep. PSW-GTR-152. Albany, CA: Pacific Southwest Research Station, Forest Service, U.S. Department of Agriculture; p. 361-370
    Publication Series: General Technical Report (GTR)
    Station: Pacific Southwest Research Station
    PDF: View PDF  (626 KB)

    Description

    We assessed the occurrence patterns of Marbled Murrelets (Brachyramphus marmoratus) offshore of Waddell Creek, in central California. Data were derived primarily from cruises during the height of the murrelet breeding season, in June, between 1986 and 1994, as well as some cruises during the prebreeding period, February to early April. The large majority of sightings occurred within 10 km of Point Año Nuevo, directly offshore the species’ breeding area. Only three sightings occurred farther offshore (12-24 km). The physical factors that explained a small but significant portion of variability in murrelet occurrence were: (1) inverse relationships related to distance to breeding area (including ocean depth); and (2) relationships to recently upwelled water. Murrelets were least abundant during periods of El Niño-Southern Oscillation. An analysis of the availability of potential prey species indicated that murrelets were most abundant when more euphausiids were found from the coast to well offshore. Murrelets were absent in years when a large prey concentration occurred only close to shore, indicating that the birds were too close to shore for us to census. We suggest that the critical habitat of this population should include the nearshore marine waters within 10 km of Año Nuevo Island.

    Publication Notes

    • You may send email to rmrspubrequest@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

    Ainley, David G.; Allen, Sarah G.; Spear, Larry B. 1995. Chapter 34: Offshore Occurrence Patterns of Marbled Murrelets in Central California. In: Ralph, C. John; Hunt, George L., Jr.; Raphael, Martin G.; Piatt, John F., Technical Editors. 1995. Ecology and conservation of the Marbled Murrelet. Gen. Tech. Rep. PSW-GTR-152. Albany, CA: Pacific Southwest Research Station, Forest Service, U.S. Department of Agriculture; p. 361-370

    Related Search


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