Chronic oiling of marine birds in California by natural petroleum seeps, shipwrecks, and other sources

Laird A. Henkel, Hannahrose Nevins, Marida Martin, Susan Sugarman, James T. Harvey, Michael H Ziccardi

Research output: Contribution to journalArticle

15 Scopus citations


We assessed temporal and spatial patterns of chronic oiling of seabirds in California during 2005-2010, using data on: (1) live oiled birds reported to the Oiled Wildlife Care Network (OWCN) from throughout the state, and (2) dead oiled birds found during systematic monthly beached-bird surveys in central California. A mean of 245 (±141 SD) live miscellaneous oiled birds (not associated with known oil spills) were reported to the OWCN per year, and 0.1 oiled dead birds km-1 per month were found on beach surveys in central California. Chemical fingerprinting of oiled feathers from a subset of these birds (n=101) indicated that 89% of samples tested were likely from natural petroleum seeps off southern and central California. There was a pronounced peak during late winter in the number of oiled birds reported in southern California, which we theorize may be related to large storm waves disturbing underwater seeps.

Original languageEnglish (US)
Pages (from-to)155-163
Number of pages9
JournalMarine Pollution Bulletin
Issue number1-2
StatePublished - Feb 15 2014



  • Monterey Formation
  • Oil fingerprinting
  • Seabirds

ASJC Scopus subject areas

  • Oceanography
  • Aquatic Science
  • Pollution

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