A sensitivity analysis to guide research and management for Hector's dolphin

• Published in: Biological conservation 1999-10, Vol.90 (3), p.183-191
• Main Authors: Martien, Karen K, Taylor, Barbara L, Slooten, Elizabeth, Dawson, Steve
• Format: Article
• Language: English
• Subjects: Animal, plant and microbial ecology; Applied ecology; Biological and medical sciences; Cephalorhynchus hectori; Conservation, protection and management of environment and wildlife; Delphinidae; Fundamental and applied biological sciences. Psychology; Gillnet mortality; Hector's dolphin; Management objectives; Marine; New Zealand; Parks, reserves, wildlife conservation. Endangered species: population survey and restocking; Sensitivity analysis
• ISSN: 0006-3207; 1873-2917
• DOI: 10.1016/S0006-3207(99)00020-8

Hector's dolphin ( Cephalorhynchus hectori) is an uncommon endemic of New Zealand which is suspected to be in decline due to entanglement mortality. However, uncertainty in available data has led to a dispute between the New Zealand Ministry of Fisheries and the New Zealand Department of Conservation over the status of this species. We use a density-dependent deterministic model to predict the future abundance and geographic distribution of Hector's dolphin under different scenarios of fisheries management. We then examine the sensitivity of this model to a number of parameters for which few or no data are available. We find that two populations of Hector's dolphins are predicted to decline in the future even when the most optimistic parameter estimates are used. The status of the third population is dependent upon the estimate of maximum annual population growth rate. Because of the dependence of final abundance estimates on the estimates of entanglement mortality rates and maximum population growth rate, research efforts should be concentrated on estimating these parameters.