Wildlife Research Wildlife Research Society
Ecology, management and conservation in natural and modified habitats

Application of decision theory to conservation management: recovery of Hector’s dolphin

Michael J. Conroy A E , Richard J. Barker B , Peter W. Dillingham B , David Fletcher B , Andrew M. Gormley B C and Ian M. Westbrooke D
+ Author Affliations
- Author Affliations

A USGS Georgia Cooperative Fish and Wildlife Research Unit, Warnell School of Forestry and Natural Resources, University of Georgia, Athens, GA 30602, USA.

B Department of Mathematics and Statistics, University of Otago, PO Box 56, Dunedin 9010, New Zealand.

C Department of Zoology, University of Otago, PO Box 56, Dunedin 9010, New Zealand.

D Department of Conservation, PO Box 13049, Christchurch, New Zealand.

E Corresponding author. Email: mconroy@uga.edu

Wildlife Research 35(2) 93-102 https://doi.org/10.1071/WR07147
Submitted: 18 September 2007  Accepted: 29 February 2008   Published: 21 April 2008


Decision theory provides an organised approach to decision making in natural resource conservation. The theory requires clearly stated objectives, decision alternatives and decision-outcome utilities, and thus allows for the separation of values (conservation and other societal objectives) from beliefs. Models express belief in the likely response of the system to conservation actions, and can range from simple, graphical representations to complex computer models. Models can be used to make predictions about likely decision-outcomes, and hence guide decision making. Decision making must account for uncertainty, which can be reduced but never eliminated. Uncertainty can be described via probabilities, which in turn can be used to compute the expected value of alternative decisions, averaging over all relevant sources of uncertainty. Reduction of uncertainty, where possible, improves decision making. Adaptive management involves the reduction of uncertainty via prediction under two or more alternative, structural models, comparison of model predictions to monitoring, and feedback via Bayes’ Theorem into revising model weights, which in turn influences decision making. As part of a 3-day workshop on structured decision making (SDM) and adaptive resource management (ARM), we constructed a prototypical decision model for the recovery for Hector’s dolphin (Cephalorynchus hectori), an endangered dolphin endemic to New Zealand coastal waters. Our model captures several steps in the process of building an SDM/ARM framework, and should be useful for managers wishing to apply these principles to dolphin conservation or other resources problems.


This work was initiated while MJC was a visiting Evans Fellow at the University of Otago, and he gratefully acknowledges the support of that fund, and of the Department of Mathematics and Statistics, University of Otago. We thank Susan Waugh for help in organising the workshop and for contributions to the discussion on Hector’s dolphins. We thank Mark Maunder and Jim Peterson for helpful comments on previous drafts. The Georgia Cooperative Fish and Wildlife Research Unit is jointly sponsored by USGS, the University of Georgia, Georgia Department of Natural Resources, US Fish and Wildlife Service, and the Wildlife Management Institute.


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