Attitudes toward sustainability and extinction

Conservation biologists and natural resource managers are both working to m aintain species, but their approaches and priorities differ. The contrast w as highlighted when the World Conservation Union (IUCN) listed some commerc ial fish species, such as the Atlantic cod (Gadus morhua), in the 1996 Red List of Threatened Animals. These species qualified under IUCN's criteria b ecause they had undergone a marked decline in abundance. Disagreements over these listings revealed fundamental differences between resource managers and conservation biologists. Resource managers aiming to maximize continuin g yields using specific, explicit, and data-rich models, generally have not considered risk assessment and sometimes face the necessity for political compromises. Conservation biologists generally consider a wide diversity of species and operate in a data-poor and precautionary context with an overa ll aim of minimizing extinction risk. The IUCN Red List is an extreme case in point and uses simple criteria for evaluating the conservation status of all species. Under these circumstances, it can do little more than indicat e a species' status in order to prompt further investigation by the appropr iate body. We suggest that procedure collaboration between conservation bio logists and resource managers will start with an understanding of these dif ferent perspectives and will benefit from common interests in precautionary approaches, ecosystem approaches, and adaptive management studies.