3. Survey area
Kahurangi National Park covers an area of 452,002 hectares and is the second largest of New Zealand's 13 national parks. It encompasses much of the north-west South Island. A selection of rivers draining the north- west corner of the park were surveyed. These include the Waingaro, Anatoki, Aorere, Anatori, Anaweka, Kahurangi, Turimawiwi, Parapara, and Big catchments. The remaining rivers in the south of the park, the Owen, Wangapeka and Matiri catchments, were surveyed by DOC, St Arnaud, between 1994 and 1998 (Studholme 2000). Some of the whio population they contain are being managed at present but a repeat survey has not been completed.