Global Seabird Response to Forage Fish Depletion—One-Third for the Birds

Determining the form of key predator-prey relationships is critical for understanding marine ecosystem dynamics. Using a comprehensive global database, we quantified the effect of fluctuations in food abundance on seabird breeding success. We identified a threshold in prey (fish and krill, termed "forage fish") abundance below which seabirds experience consistently reduced and more variable productivity. This response was common to all seven ecosystems and 14 bird species examined within the Atlantic, Pacific, and Southern Oceans. The threshold approximated one-third of the maximum prey biomass observed in long-term studies. This provides an indicator of the minimal forage fish biomass needed to sustain…

• NS
  National Science Foundation

  Award: 0929017
• ID
  Institut de Recherche pour le Développement
• EV
  Exxon Valdez Oil Spill Trustee Council
• SR
  Sight Research UK

  Award: bas0100025
• NR
  National Research Foundation
• N
  Naturvårdsverket
• DO
  Department of Agriculture, Forestry and Fisheries
• NO
  National Oceanic and Atmospheric Administration
• UF
  U.S. Fish and Wildlife Service
• UG
  U.S. Geological Survey
• NE
  Natural Environment Research Council

  Award: bas0100025
• NM
  National Marine Fisheries Service
• BA
  British Antarctic Survey