Forecasting an Ecosystem's Point of No Return
Image credit: Matt Callow/Flickr
Most conservation, unfortunately, is reactive. Though improved assessment methods make this reaction more timely, plans are crafted after habitats are degraded and species are recieve protected status after their populations have demonstrated critical declines.
New research, however, could help conservationists pinpoint the moment a species will take a turn towards the unrecoverable—knowledge that could change the way preservation plans are designed and implemented.John M. Drake, a professor at the University of Georgia, and Blaine Griffen, a professor at the University of South Carolina, used a commonly cited but little understood principle to demonstrate trends in stressed populations can be predicted.
Called "critical slowing down," the principle describes a decreasing rate of recovery in systems approaching a tipping point. Drake explained:
The theory was originally used to describe drastic changes in other kinds of systems—everything from epileptic seizures to regime shifts in the earth's climate system...but these attributions of CSD primarily have been after-the-fact explanations of anomalous observations without clear controls.
In this latest experiment, populations of water fleas where placed under increasing stress, represented by a lack of food, and compared to a healthy control group. It was the first time CSD was applied to a biological system—let alone extinction.
By observing changes in a range of indicators in relation to the decreasing availability of food, researchers were able to predict the onset of the tipping point well before it arrived.
The incredible thing about the finding, Drake explained, was its generality. He said:
You don't have to know the underlying equations to use the theory...and this is important in biology, where the dynamics are typically sufficiently complex that we often do not know which equations to use. In fact, we may never come to such a complete understanding, given the range of biodiversity out there and the fact that species are evolving all the time.
Though the findings are still a long way from practical application, they represent, Drake argues, the first step towards a system that could accurately predict approaching tipping points—something that would be a powerful tool for conservation planning.
Read more about conservation:
Wildlife Trapped by Global Biodiversity Surveillance System (Photos)
Life on the Endangered Species Waiting List
The Problem With 'Shoot to Kill' Conservation
6 Conservation Successes That Brought Animals Back from the Brink