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An improved technique for indexing abundance of Himalayan thar

Current monitoring of Himalayan thar (Hemitragus jemlahicus) populations in New Zealand involves a technique based on repeated observations by different, experienced observers. The method gives no measure of error and hence does nor allow for statistical comparison of repeated surveys. We outline a faster and cheaper technique that enables statistical comparison between surveys based on mark-recapture theory.

Distance sampling to determine kaka (Nestor meridionalis septentrionalis) density within Waipapa Ecological Area, Pureora

Reliable information about population density and trends is essential for making valid inferences regarding conservation management. The suitability of point counts using distance sampling was examined as a means of monitoring a population of kaka (Nestor meridionalis septentrionalis), a large forest-dwelling parrot, inhabiting the Waipapa Ecological Area in the central North Island of New Zealand. Counts were conducted on 13 occasions between 2000 and 2007.