Busy Beavers Fight Drought

Beavers build dams that offset the effects of drought, a new study suggests. They therefore shouldn't be disturbed.

The study, published in the online edition of Biological Conservation, found that over the span of five decades, the presence of beavers and their dams increased the presence of open water by up to nine times.

The researchers also concluded that other climate variables, such as temperature and precipitation, were much less important than beavers in maintaining open water areas in the boreal forest wetlands.

"In times of drought, they may be one of the most effective ways to mitigate wetland loss," said Glynnis Hood, an environmental science professor at the University of Alberta who lead the study. "Some people believe climate is driving everything, but the presence of beaver has a dramatic effect on the availability of open water in an area."

While climate models predict longer and more frequent droughts in parts of North America over the next century, beaver colonies may help lessen the impact by providing habitat and water resources for other animals and livestock. Their dams can even recharge groundwater reserves.

Yet many dams are being removed for the sake of urban and industrial expansion.

"Removal of beaver should be considered an environmental disturbance on par with in-filling, peat mining and industrial water extraction," Hood said.

--LiveScience Staff 

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