Beavers are contributing to climate change, adding an estimated 800 million kg of methane to the atmosphere every year, scientists have found.
Over the last century, there has been a worldwide conservation effort to save beavers from extinction. The fur trade between the 16th and 19th century almost led to the annihilation of beavers across the globe.
After trapping was limited and the creatures were reintroduced to their natural ranges, their numbers grew significantly, with scientists now estimating their population to have reached over 10 million worldwide.
However, the consequence of this has led to beavers building more ponds, creating conditions for climate changing methane gas to be generated in the shallow standing water. Beavers build dams in rivers to create standing ponds, with dams normally reaching no higher than 1.5m.
In their work published in the Springer journal AMBIO, experts note that carbon builds up in oxygen-poor pond bottoms like those created by beavers, and methane is generated. The gas cannot be dissolved and is released into the atmosphere.