Sightings of southern right whales around ‘mainland’ New Zealand SCIENCE FOR CONSERVATION 225 Nathalie J. Patenaude Published by Department of Conservation PO Box 10-420 Wellington, New Zealand Science for Conservation is a scientific monograph series presenting research funded by New Zealand Department of Conservation (DOC). Manuscripts are internally and externally peer-reviewed; resulting publications are considered part of the formal international scientific literature. Titles are listed in the DOC Science Publishing catalogue on the departmental website http:// www.doc.govt.nz and printed copies can be purchased from
[email protected] © Copyright July 2003, New Zealand Department of Conservation ISSN 1173–2946 ISBN 0–478–22454–0 In the interest of forest conservation, DOC Science Publishing supports paperless electronic publishing. When printing, recycled paper is used wherever possible. This report was prepared for publication by DOC Science Publishing, Science & Research Unit; editing by Jaap Jasperse and layout by Ruth Munro. Publication was approved by the Manager, Science & Research Unit, Science Technology and Information Services, Department of Conservation, Wellington. CONTENTS Abstract 5 1. Introduction 6 1.1 Southern right whales in New Zealand waters 7 2. Purpose of research 8 3. Methods 9 3.1 Collation of sightings and photographs 9 3.2 Photo-identification and matching 10 4. Results 11 4.1 Sighting database 11 4.2 Trends in abundance 11 4.3 Distribution 14 4.4 Seasonality 15 4.5 Residence time 15 4.6 Behaviour 18 4.7 Photo-identification 19 5. Discussion 19 5.1 Limitations and biases 19 5.2 Evidence of a significant recovery of southern right whales around mainland New Zealand 20 5.3 Identifying important NZ coastal habitat for right whales 20 5.4 Determining residence time and behaviour of right whales 21 5.5 Determining by photo-identification matching if the right whales around mainland NZ represent a separate stock 21 5.6 Management recommendations 23 6.