Changes in abundance and distribution of the rock wren (Xenicus gilviventris) in the South Island, New Zealand

Abstract

We collected and collated more than 2400 records of the rock wren Xenicus gilviventris, covering the period 1912-2005. These records allowed past and present distribution patterns to be mapped and compared. Areas from which birds have apparently disappeared were identified. The rock wren was common once on mountain ranges along or close to the Southern Alps, South Island, New Zealand, but have been recorded less frequently in many areas after 1980. More numerous records from some areas and during some decades could have resulted from differences in search effort and from inconsistency in record keeping. Nevertheless, there were consistent anecdotal accounts of decline, evidence of predation by stoats and mice, unsuccessful searches in previous strongholds and the recent extinction of 5 confamilial species indicate that the rock wren should be regarded as a threatened species.