Optimal Australian dugong populations and conservation plans: An economic perspective

Australia provides one of the last refuges globally for the sea mammal Dugong dugon, an inhabitant of the Queensland coast and other northern Australian waters. In response to declining dugong numbers, some ecologists have strongly advocated extensions of dugong protected areas in Queensland. In these areas, gill net fishing is banned. This raises the question of what is the optimal population of dugong (and similar species) and whether economic factors should play a role in its determination. Ecologists recommending extended dugong protected areas pay no attention to economic factors so their analysis is far from holistic. As discussed, economics is relevant to assessing the cost-effectiveness of alternative conservation strategies and social cost-benefit analysis can throw further light on the social dimensions of the problem, even though A.C. Pigou's view that welfare economics only yields partial answers should be heeded. Furthermore, even application of precautionary principles and safe minimum standards requires account to be taken of economic considerations, as recognised by amendments to the Endangered Species Act of the US. The ecologists in this dugong protection case ignore all such considerations