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Providing evidence to improve practice

Individual study: Large-scale control of introduced mammalian predators improves kaka Nestor meridionalis breeding success on North and South Islands, New Zealand

Published source details

Moorhouse R., Greene T., Dilks P., Powlesland R., Moran L., Taylor G., Jones A., Knegtmans J., Wills D., Pryde M., Fraser I., August A. & August C. (2003) Control of introduced mammalian predators improves kaka Nestor meridionalis breeding success: reversing the decline of a threatened New Zealand parrot. Biological Conservation, 110, 33-44


This study is summarised as evidence for the intervention(s) shown on the right. The icon shows which synopsis it is relevant to.

Control predators not on islands for parrots Bird Conservation

A replicated, controlled trial in New Zealand (Moorhouse et al. 2003) found that the nesting success of kakas Nestor meridionalis was significantly higher at three sites with control (80–87% of 70 nests successful) than at three unmanaged sites (10–38% of 43 nests). Predation rate of nesting females was also significantly lower at sites with predator control (5% of 38 tracked females vs. 65% of 17). Stoats Mustela erminea, common brushtail possums Trichosurus vulpecula and rats Rattus spp. were controlled with trapping and poisoning with 1080 sodium monofluoroacetate and anticoagulents. Data comes from 1996-2000 for five sites and 1984-1996 for one (unmanaged) site.