Titi (sooty shearwaters) on Whero Island: Analysis of historic data using modern techniques
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A reanalysis of titi (sooty shearwater, Puffinus griseus) banding data collected between 1940 and 1957 by Lance Richdale demonstrates that well-documented archival material can be usefully reanalyzed using newly developed statistical techniques. In this study, we compare the results obtained by Richdale using empirical techniques to those obtained using a multistate mark-recapture model. Although the two approaches produce similar estimates for some of the parameters, the multistate model additionally provides estimates of precision and can be used to answer biologically significant questions not raised by the original worker. Our analysis provides some evidence for two conclusions that Richdale put forward but could not justify rigorously: (a) nonbreeders have a lower survival rate than breeders, although the difference is not statistically significantly; and (b) nonbreeders are more difficult to capture than breeders. We argue that reanalysis should be carried out more frequently on historical data and lament the fact that it can be rare for such data to be made available for future scrutiny.
Key WordsArchival data Mark-recapture Multistate model Puffinus griseus Reanalysis
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- Burnham, K. P. (in press), “On Random Effects Models for Tag-Recovery and Capture-Recapture Data,” in Statistics in Ecology and Statistics in Ecology and Environmental Monitoring III, Dunedin, New Zealand; Otago University Press.Google Scholar
- Cuthbert, R., Fletcher, D., and Davis, L. S. (in press), “A Sensitivity Analysis of Hutton’s Shearwater: Prioritizing Conservation, Research and Management,” Biological Conservation.Google Scholar
- Lack, D. (1968), Ecological Adaptations for Breeding in Birds, Oxford: Oxford University Press.Google Scholar
- Loery, G., Nichols, J. D., and Hines, J. E. (1997), “Capture-Recapture Analysis of a Wintering Black-Capped Chickadee Population in Connecticut, 1958–1993,” Auk, 114, 431–442.Google Scholar
- Oka, N., Maruyama, N., and Skira, I. (1987), “Chick Growth and Mortality of Short-Tailed Shearwaters in Comparison With Sooty Shearwaters, as a Possible Index of Fluctuations of Australian Krill Abundance,” Proceedings of the National Institute of Polar Research Symposium on Polar Biology, 1, 166–174.Google Scholar
- Richdale, L. E. (1942), “Whero: Island Home of Petrels and Other Birds,” Emu, 42, 85–105.Google Scholar
- — (1943), “Whero: Island of Sea-Birds,” Wild Life Series, 1, 26–40. Dunedin: Otago Daily Times.Google Scholar
- — (1963), “The Biology of the Sooty Shearwater Puffinus griseus,” Proceeding of the Zoological Society of London, 31, 1–86.Google Scholar
- Warham, J., and Wilson, G. J. (1982), “The Size of the Sooty Shearwater Population at the Snares Islands, New Zealand,” Notornis, 29, 23–30.Google Scholar
- Wooller, R., and Bradley, S. (1996), “Monogamy in a Long-Lived Seabird: The Short-Tailed Shearwater,” in Partnerships in Birds. The Study of Monogamy, ed. J. M. Black, Oxford: Oxford University Press, pp. 223–234.Google Scholar