They may look cute and harmless, but squirrels and beavers are contributing to climate change far more than previously thought, climate scientists have claimed. However, their discovery doesn’t let us humans off the hook, as the scientists still insist that carbon dioxide emissions are causing arctic permafrost to melt, compounding the squirrels’ efforts, the Daily Mail has reported.
According to researchers working on the Polaris Project in the Arctic, which aims to study climate change at the poles, arctic ground squirrels and beavers both contribute to carbon emissions by burrowing into the frozen soil to make their homes, churning up the soil. Faeces and urine from the rodents fertilises the soil, encouraging decomposition of biological material that had been locked in suspended animation by the frost, releasing greenhouse gases into the atmosphere.
Nigel Golden, an ecologist at the University of Wisconsin who took part in the project told the BBC that the ground temperature around the rodents’ burrows was higher than in the surrounding area. “’They are soil engineers,” he said. “They break down the soil when they are digging their burrows, they mix the top layer with the bottom layer, they are bringing oxygen to the soil and they are fertilizing the soil with their urine and their faeces.
“We saw an increase in soil temperature in the soils where the arctic ground squirrels were occupying. This is a major component. As that permafrost begins to warm, now microbes can have access to these previously frozen carbons that were in the soil. And because they mix the soil layers, they are being exposed to warmer temperatures.”