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MEPS Marine Ecology Progress Series Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsTheme Sections MEPS 227:43-50 (2002) - doi:10.3354/meps227043 Oceanographic and climatic factors influencing breeding and colony attendance patterns of Humboldt penguins Spheniscus humboldti in central Chile Alejandro Simeone1,*, Braulio Araya2, Mariano Bernal3, Edward N. Diebold4, Karen Grzybowski5, Margaret Michaels5, J. Andrew Teare6, Roberta S. Wallace5, Mary Jo Willis7 1Institut für Meereskunde, Düsternbrooker Weg 20, 24105 Kiel, Germany 2Anakena 2311, Departamento 208, Viña del Mar, Chile 3Instituto de Oceanología, Universidad de Valparaíso, Casilla 13-D, Viña del Mar, Chile 4Riverbanks Zoological Park and Botanical Garden, PO Box 1060, Columbia, South Carolina 29202, USA 5Milwaukee County Zoo, 10001 West Bluemound Road, Milwaukee, Wisconsin 53226, USA 6Jacksonville Zoo, 8605 Zoo Parkway, Jacksonville, Florida 32218, USA 7Denver Zoological Foundation, 2900 E. 23rd Avenue, Denver, Colorado 80205, USA *E-mail: asimeone@ifm.uni-kiel.de ABSTRACT: A colony of Humboldt penguins Spheniscus humboldti in central Chile was monitored from August 1995 to July 2000 to determine patterns of breeding and colony attendance and how these were affected by climatic (rainfall) and oceanographic (El Niño) factors. Nests were periodically checked for contents and roosting birds were counted from vantage points. Two main breeding events were observed: between August and January (spring event) and between April and June (autumn event). Whereas the spring event regularly produced offspring, the autumn event was systematically affected by rains, causing considerable nest desertion. Adults were present in the colony from August to May, abandoning the colony during winter after the nests were flooded. Juveniles occurred only between November and March. Adults moulted mainly in February, while juveniles moulted in January. During the 1997/98 El Niño episode, the number of breeding pairs was 55 to 85% lower than the mean, the onset of nesting was delayed, and abnormally heavy rainfall flooded nests. While the number of breeding pairs was significantly related to sea surface temperature anomalies (SSTA), breeding success was not. The attendance of adults and juveniles at the colony during El Niño was 25 and 73% lower, respectively, than the mean attendance. This 2-peak breeding strategy of Humboldt penguins appears to have evolved in response to the more favourable oceanographic and climatic conditions of Perú, where breeding is continuous and not interrupted by rains. Although less productive, the species probably maintains its autumnal breeding in central Chile because this provides additional offspring to supplement those regularly produced during the spring event. KEY WORDS: Humboldt penguin · Spheniscus humboldti · El Niño · Nest desertion · Breeding · Colony attendance Full text in pdf format PreviousNextExport citation RSS - Facebook - Tweet - linkedIn Cited by Published in MEPS Vol. 227. Online publication date: February 13, 2002 Print ISSN: 0171-8630; Online ISSN: 1616-1599 Copyright © 2002 Inter-Research.