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Measuring Success in Conservation

Assessing efforts to restore populations of marine mammals is partly a matter of epistemology: How do you know when enough is enough?

Leah Gerber, Douglas DeMaster, Simona Roberts

Ecological consciousness has been rising in the United States and Europe over the past 30 years, making people more aware of their guardianship of the earth's natural resources. In the recent past, several projects have been launched to catalogue all living species in an attempt to protect them from extinction. But this sense of protectionism is not applied evenly to all species. Every year, populations of plants, insects and even microbes reach the brink of extinction, virtually unnoticed. In the meantime, the threat of large-mammal extinctions arouses public passions, attention and, ultimately, money. It is here, at the intersection of sentimentality and scientific controversy that conservation biologists typically face their greatest challenge.

This challenge is twofold. First, biologists need to determine which populations really need recovery action, and just as important, we need to know when a population no longer requires our intervention. Clearly, the efficiency with which these are done can have important economic consequences. Inefficient assessment of conservation activities can lead to economic inequities. It can lead groups to spend money on animal populations that have recovered at the expense of other, lesser known, and possibly less photogenic species that actually need the help. In short, a well-defined ecological policy could translate into sound economic policy as well. Yet putting sound conservation policies into place is hardly straightforward.

The Endangered Species Conservation Act (ESCA) of 1969 and its 1973 iteration, the Endangered Species Act (ESA), defined categories for endangered and threatened species but provided no criteria for deciding when a species should be listed, delisted or "downlisted" from endangered to threatened. As a result, listing and recovery actions for marine mammals, as well as other species, are widely inconsistent. The ESA was amended in 1988 to require that recovery plans include specific criteria to determine when a species should be removed from the List of Endangered and Threatened Wildlife. Nevertheless, our own work with whales has shown this to be a rather sticky epistemological problem. We are barely at the point that we can determine with any kind of certainty when a population has recovered. Recognizing this, we have been working to solve this problem for several populations of endangered whales with the hope that it will move us into a time where rigorous data collection and analysis, and not sentimentality, drive conservation policy.

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