Effects of the 1982-83 El Niño – Southern Oscillation on Pacific Ocean bird populations

David G. Ainley; H.R. Carter; Daniel W. Anderson; Kenneth T. Briggs; Malcom C. Coulter; F. Cruz; J.B. Cruz; C.A. Valle; S.I. Fefer; Scott A. Hatch; Elizabeth Anne Schreiber; Ralph W. Schreiber; N.G. Smith

USGS · 70189788

Effects of the 1982-83 El Niño – Southern Oscillation on Pacific Ocean bird populations

David G. Ainley·H.R. Carter·Daniel W. Anderson·Kenneth T. Briggs·Malcom C. Coulter·F. Cruz·J.B. Cruz·C.A. Valle·S.I. Fefer·Scott A. Hatch·Elizabeth Anne Schreiber·Ralph W. Schreiber·N.G. Smith

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Abstract

Seabird reproductive success, population size, and movements in the Pacific region responded dramatically to the 1982-83 El Niño – Southern Oscillation (ENSO). At sites within the North and South Pacific Gyres, the onset of seabird responses tracked oceanographic changes related to ENSO; to the north of the gyres, responses were delayed 1 yr. Reproductive failures and high adult mortality were detected at all sites investigated. Post-ENSO, the return to “normal” nesting patterns depended on species and locality. The 1982-83 ENSO revealed a dimension to the variability in seabird reproductive biology only now appreciated by ornithologists.

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David G. Ainley, H.R. Carter, Daniel W. Anderson, Kenneth T. Briggs, Malcom C. Coulter, F. Cruz, J.B. Cruz, C.A. Valle, S.I. Fefer, Scott A. Hatch, Elizabeth Anne Schreiber, Ralph W. Schreiber, N.G. Smith. 1988. Effects of the 1982-83 El Niño – Southern Oscillation on Pacific Ocean bird populations. https://pubs.usgs.gov/publication/70189788

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