Clutch parameters and reproductive success of a translocated population of red-crowned parakeet (Cyanoramphus novaezelandiae)
Luis Ortiz-Catedral A B and Dianne H. Brunton AA Ecology and Conservation Group, Institute for Natural Sciences, Massey University, Albany Campus, Private Bag 102-904 North Shore Mail Centre, Auckland, New Zealand.
B Corresponding author. Email: l.ortiz-catedral@massey.ac.nz
Australian Journal of Zoology 56(6) 389-393 https://doi.org/10.1071/ZO08069
Submitted: 27 August 2008 Accepted: 2 February 2009 Published: 13 March 2008
Abstract
At least four populations of the red-crowned parakeet (Cyanoramphus novaezelandiae) have been established via translocation within New Zealand over the last 40 years, but reproductive parameters of these populations have not been documented. We quantified differences in clutch parameters and reproductive success for a translocated population of this species on Tiritiri Matangi Island over two breeding seasons. Overall clutch parameters and estimates of reproductive success were consistent with reported values from natural populations. However, we found previously unreported differences in clutch size, hatching success and brood size between breeding seasons. The number of fledglings produced per breeding pair increased significantly from 1.4 to 3.4 fledglings during our two-year study. In contrast, egg volume and fertility per clutch did not vary during the same period. Overall, 7 eggs were laid per breeding pair but only 2.22 nestlings fledged, representing a 63.8% loss of initial reproductive potential. Losses during the incubation stage were caused by partial and total hatching failure, whereas starvation of nestlings caused all losses during the brood-rearing stage. Hatching success during our study was lower than that reported for wild populations of this and other parrot species, and remained lower even during the most productive breeding season. We found no cases of predation on eggs or nestlings during our study despite the presence of native and exotic avian predators on Tiritiri Matangi Island. We show that clutch size, brood size and changes in loss between breeding seasons are determinants of reproductive output in translocated red-crowned parakeet and also that reproductive output can vary greatly between breeding seasons. Finally, if reduced hatching success is the result of small founder size, management of parakeets should consider the movement of larger and more genetically diverse flocks.
Acknowledgements
This research was conducted under full approval by the New Zealand Department of Conservation (permit AK/15301/RES) and approved animal-handling protocols by the Animal Ethics Committees of Auckland University (protocol AEC/08/2004/RS81) and Massey University (Protocol 05/74). We appreciate the financial support obtained from the National Council of Science and Technology of Mexico (CONACYT) (a scholarship to the first author), Supporters of Tiritiri Matangi Inc., The Parrot Society UK, Sigma Xi The Scientific Research Society and Stiftung Avifauna Protecta. Idea Wild provided a portable computer for data collection in the field. Fuller Ferries and Kawau Kat Cruises provided numerous discount ferry tickets during our research. We are also grateful to all the volunteers who helped in the field with data collection. Finally, we thank Marleen Baling, Mark Hauber, Michael Anderson, Weihong Ji and the anonymous reviewers whose comments improved this manuscript.
Beggs, J. R. , and Wilson, P. R. (1991). The kaka Nestor meridionalis, a New Zealand parrot endangered by introduced wasps and mammals. Biological Conservation 56, 23–38.
| Crossref | GoogleScholarGoogle Scholar |
Elliott, G. P. , Dilks, P. J. , and O’Donnell, C. F. J. (1996). The ecology of yellow-crowned parakeets (Cyanoramphus auriceps) in Nothofagus forest in Fiordland, New Zealand. New Zealand Journal of Zoology 23, 249–265.
Jamieson, I. G. (2003). No evidence that dietary nutrient deficiency is related to poor reproductive success of translocated takahe. Biological Conservation 115, 165–170.
| Crossref | GoogleScholarGoogle Scholar |
Keller, L. F. , and Waller, D. M. (2002). Inbreeding effects in wild populations. Trends in Ecology & Evolution 17, 230–241.
| Crossref | GoogleScholarGoogle Scholar |
Mitchel, N. (1985). The revegetation of Tiritiri Matangi Island: the creation of an open sanctuary. Annual Journal of the Royal New Zealand Institute of Horticulture 13, 36–41.
Ortiz-Catedral, L. , and Brunton, D. H. (2009). Nesting sites and nesting success of reintroduced red-crowned parakeets (Cyanoramphus novaezelandiae) on Tiritiri Matangi Island, New Zealand. New Zealand Journal of Zoology 35, 1–10.
Tatum, J. B. (1975). Egg volume. The Auk 92, 576–580.
Taylor, S. S. , Jamieson, I. G. , and Armstrong, D. P. (2005). Successful island reintroductions of New Zealand robins and saddlebacks with small numbers of founders. Animal Conservation 8, 415–420.
| Crossref | GoogleScholarGoogle Scholar |
Westemeier, R. L. , Brawn, J. D. , Simpson, S. A. , Esker, T. L. , Jansen, R. W. , Walk, J. W. , Kershner, E. L. , Bouzat, J. L. , and Paige, K. N. (1998). Tracking the long-term decline and recovery of an isolated population. Science 282, 1695–1698.
| Crossref | GoogleScholarGoogle Scholar | CAS | PubMed |
