"The authors acknowledge that otters probably aren't the answer to rising CO2 levels"

Sea Otters May Be Global Warming Warriors | LiveScience

Sea otters might be on the frontlines of the fight against global warming. A new study shows that the fur-coated swimmers keep sea urchin populations in check, which in turn allows CO2-sucking kelp forests to prosper.
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The authors acknowledge that otters probably aren't the answer to rising CO2 levels, a major contributing factor to global warming, but the researchers say their study illustrates the impact animals can have on the atmosphere.