Beavers through their dams and the ecologies (microbes etc created) de-couple nitrogen from the water. It matters because our fertilizer run-off has created too much nitrogen in the water which creates algae blooms and kills fish... basically rupturing the equilibrium. So, today more beavers could mean better ecology. Beavers also help (re)distribute water in ways that could smartly conserve it for an ecological future. Could we save California through beaver engineering? Take that human dam builders! Hoover dam and Glenn Canyon have nothing on the humble beaver!
