Consequences of La Niña phase of ENSO for the survival and growth of nestling Burrowing Parrots on the Atlantic coast of South America
Juan F. Masello A B and Petra Quillfeldt AA Institut für Ökologie, Friedrich-Schiller-Universität Jena, Germany, and Institute of Biochemical and Life Sciences, University of Glasgow, UK.
B Present address: Ecology of Vision Group, School of Biological Sciences, University of Bristol, Woodland Road, Bristol BS8 1UG, UK. Email: Juan.Masello@bristol.ac.uk
Emu 104(4) 337-346 https://doi.org/10.1071/MU03039
Submitted: 19 August 2003 Accepted: 22 June 2004 Published: 16 December 2004
Abstract
Birds are sensitive to perturbations in climate. Changes in reproductive ecology may reflect changes in food availability caused by environmental conditions. We studied the influence of the La Niña phase of the El Niño Southern Oscillation (ENSO) on breeding success and survival and growth of nestling Burrowing Parrots (Cyanoliseus patagonus) (Aves, Psittaciformes) in Patagonia. During the breeding season 1998−99, a severe drought affected the region as a consequence of a strong La Niña. We compare data from a La Niña event with an average year. Clutch sizes were similar in the two years. In both years, clutch size declined during the season. Our results suggest that environmental conditions are not the primary determinant of clutch size in Burrowing Parrots, and seasonal differences are more likely caused by differences in adult quality. Nestling mortality was higher during La Niña, while the surviving nestlings showed reduced growth. Hatching order had a stronger influence on growth and survival of nestlings during La Niña than during the average year. Last-hatched nestlings always showed reduced growth compared with middle- and first-hatched nestlings, but the difference between nestlings was greater during La Niña.
Acknowledgments
We thank Adrián Pagnossin, María Luján Pagnossin and Mara Marchesan for their help in the field, Roger Mundry for statistical advice, and the Servicio Meteorológico Nacional (Argentina) for providing the precipitation data. This project was partially supported by the City Council of Viedma Río Negro, Argentina, and a grant of the state of Thuringia, Germany (Landesgraduiertenstipendium). The present study was carried out under permission of the Dirección de Fauna de la Provincia de Río Negro, Argentina (Exp. no. 143089-DF-98).
Amundsen, T. , and Slagsvold, T. (1996). Lack’s brood reduction hypothesis and avian hatching asynchrony: what’s next? Oikos 76, 613–620.
Forbes, S. , Glassey, B. , Thornton, S. , and Earle, L. (2001). The secondary adjustment of clutch size in Red-winged Blackbirds (Agelaius phoeniceus). Behavioral Ecology and Sociobiology 50, 37–44.
| Crossref | GoogleScholarGoogle Scholar |
Holmgren, M. , Scheffer, M. , Ezcurra, E. , Gutiérrez, J. R. , and Mohren, G. M. J. (2001). El Niño effects on the dynamics of terrestrial ecosystems. Trends in Ecology & Evolution 16, 89–94.
| Crossref | GoogleScholarGoogle Scholar |
Leonardi, G. , and Oporto, N. R. (1983). Biogenetic erosion structures (modern parrots’ nests) on marine and fluvial cliffs in Southern Argentina. Anais da Academia Brasileira de Ciências 55, 293–295.
Rowley, I. , and Chapman, G. (1991). The breeding biology, food, social organisation, demography and conservation of the Major Mitchell or Pink Cockatoo, Cacatua leadbeateri, on the margin of the Western Australia wheat-belt. Australian Journal of Zoology 39, 211–261.
Spear, L. B. , Ballance, L. T. , and Ainley, D. G. (2001). Response of seabirds to thermal boundaries in the tropical Pacific: the thermocline versus the Equatorial Front. Marine Ecology Progress Series 219, 275–289.
Stoleson, S. H. , and Beissinger, S. R. (1997). Hatching asynchrony, brood reduction, and food limitation in a Neotropical parrot. Ecological Monographs 67, 131–154.
Timmermann, A. , Oberhuber, J. , Bacher, A. , Esch, M. , Latif, M. , and Roeckner, E. (1999). Increased El Niño frequency in a climate model forced by future greenhouse warming. Nature 398, 694–697.
| Crossref | GoogleScholarGoogle Scholar |
Tudhope, S. , and Collins, M. (2003). The past and future of El Niño. Nature 424, 261–262.
| Crossref | GoogleScholarGoogle Scholar |
Wingfield, J. C. , Ramos-Fernandez, G. , Nuñez de la Mora, A. , and Drummond, H. (1999). The effects of an “El Niño” Southern Oscillation event on reproduction in male and female blue-footed boobies, Sula nebouxii. General and Comparative Endocrinology 114, 163–172.
| Crossref | GoogleScholarGoogle Scholar |
Wright, T. F. , Toft, C. A. , Enkerlin-Hoeflich, E. , González-Elizondo, J. , and Albornoz, M. , et al. (2001). Nest poaching in Neotropical parrots. Conservation Biology 15, 710–720.
| Crossref | GoogleScholarGoogle Scholar |