rdf-syntax-grammar
mods:
  schema location: http://www.loc.gov/mods/v3 http://www.loc.gov/standards/mods/v3/mods-3-2.xsd
  title info:
    title: Waterfowl migration on Klamath Basin National Wildlife Refuges, 1953-2001
  name:
    name part: Gilmer, David S.
  type of resource: text
  genre: bibliography
  origin info:
    place:
      place term: vau
    date issued: 2004
    issuance: monographic
  language:
    language term: eng
  physical description:
    form: electronic
    form: remote
    extent: v, 66 pages : digital, PDF file.
  abstract: The Klamath Basin National Wildlife Refuge (NWR) complex, located in northeastern California and southern Oregon, is situated on a major Pacific Flyway migration corridor connecting waterfowl breeding grounds in the north with major wintering grounds in California and Mexico. The complex comprises five waterfowl refuges including Lower Klamath NWR, Tule Lake NWR, Upper Klamath NWR, Klamath Marsh NWR, and Clear Lake NWR, and one bald eagle refuge, Bear Valley NWR. Lower Klamath and Tule Lake NWRs are the largest refuges in the complex; historically, they supported some of the greatest autumn and spring concentrations of migrating waterfowl in North America. Starting in 1953, standardized waterfowl surveys from small aircraft have been conducted in autumn through spring. This report summarizes waterfowl migration activity (i.e., abundance, species composition, distribution on refuges, and chronology) over four time periods--the long-term (1953-2001), early (1953-76), recent (1977-2001), and the most recent (1998-2001)--to describe changing patterns of migration on Klamath Basin refuges from autumn 1953 to spring 2001. Over the long term, waterfowl abundance (birds per day) on the refuge complex averaged about 1.0 million in autumn and about 360,000 in spring. A record peak count of 5.8 million waterfowl was recorded September 24-25, 1958. Average abundance of autumn staging waterfowl for the refuge complex, after reaching record levels in the 1950s and early 1960s, began a decline that lasted until the 1980s. A gradual recovery occurred during the 1990s, but autumn abundance has not recovered to pre-1970 levels. In contrast to autumn, average spring abundance was generally lower in the early decades but has gradually increased through the 1990s, particularly on Lower Klamath NWR. Dabbling ducks represented an average of 68% of all waterfowl in autumn and 55% in spring for the long term. Northern pintail (Anas acuta) was dominant, representing 62% of all dabblers in au…
  note: by David S. Gilmer [and others].
  note: Title from Web page (viewed on Aug. 31, 2007).
  note: Electronic resource.
  note: Mode of access: Internet from the USGS web site. Address as of 2/5/08: http://www.werc.usgs.gov/dixon/pdfs/Klamath%5FBasin.pdf ; current access via PURL.
  note: Includes bibliographical references (pages 23-26).
  subject:
    geographic code: n-us-ca
    geographic code: n-us-or
  subject:
    topic: Waterfowl
    topic: Migration
    geographic: Klamath River Watershed (Or. and Calif.)
  classification: I 19.209:2003-0004
  related item:
    name:
      name part: Waterfowl migration on Klamath Basin National Wildlife Refuges, 1953-2001
    physical description:
      extent: v, 66 p.
    identifier: (DLC) 2003020513
    identifier: (OCoLC)53090907
  related item:
    title info:
      title: Biological science report ; USGS/BRD/BSR--2003-0004
  identifier: https://purl.fdlp.gov/GPO/LPS90183
  record info:
    record content source: ORE
    record creation date: 070831
    record change date: 20211129155552.0
    record identifier: in00002389679