Abstract:
Finsch's duck (Chenonetta finschi), an extinct, possibly flightless New Zealand endemic, was widely distributed and apparently abundant immediately before human settlement of New Zealand, but its bones have rarely been identified in archaeological sites. Its extinction has been variously attributed to habitat changes, predation by the introduced Pacific rat (Rattus exulans), and human predation. Discriminating between possible causes of its extinction hinges on determining the relative timing of phases of the extinction process and the arrival of rats and humans. Methodological problems of determining the time of extinction of fossil species are reviewed. Bayesian statistical analysis of a series of accelerator mass spectrometry 14C ages on gelatin from Finsch's duck bones from non-cultural deposits suggests that the species began to decline before widespread Polynesian settlement and that it was much reduced in range and numbers by the time extensive human predation and habitat alteration began. Possible causes of its extinction after Polynesian settlement are discussed.