Penny-Wise Preservation

Should conservationists give up on saving some species nearing extinction today for the chance to save even more species down the road? That is the question tackled by a new study that examines how best to allocate severely limited resources to address the threat of extinction.

“The threats to biodiversity are increasing and conservation efforts for threatened species are not sufficient,” four researchers write in Ecology Letters. “Conservation practitioners and the public alike are often polarized as to what constitutes the wise use of a limited budget.”

Some suggest that focusing resources on today’s most endangered species will save the greatest number of species in the long term. Others advocate a strategy known as “triaging,” or prioritizing resources with cost efficiency in mind. That means sometimes even allowing some species to go extinct. (Triaging originated as a medical concept in which emergency care givers abandon hopeless cases, treat more serious cases first, and put less serious cases on hold.)

To determine the best bang for the conservation buck, the research team created a cost-benefit model that accounted for the probability of extinction and the costs of saving 32 species, and then they crunched the numbers to maximize the number of species saved.

They found that focusing resources only on the most-endangered species “will not typically maximise the number of species saved, as this does not take into account the risk of less-endangered species going extinct in the future.” In contrast, over the long term, conservationists can “recover as many species as possible by allocating resources based on the lowest expected cost of recovery.” This will result in a short-term tradeoff for long-term gains, the team notes. “In the short-term, there would be relatively fewer species extant when compared with spending on more endangered species, whereas at longer time periods, there would be relatively more species extant.”

The model highlights the need to shift resources away from saving a relatively small number of highly threatened species today, they argue. “As in medicine,” they conclude, “more emphasis should be placed on long-term preventive conservation rather than short-term fire-fighting.” Matthew Dieter | July 19, 2011

Source: Howard B. Wilson, et al. When should we save the most endangered species? Ecology Letters (2011). DOI: 10.1111/j.1461-0248.2011.01652.x

Image © John Brueske |