Water voles are Britain's fastest declining mammal, with American mink predation driving local extinctions and welfare losses at population scale.
Water voles killed by mink experience acute predation trauma. The social stress of mink presence — even without predation — suppresses breeding and causes colony abandonment. Voles fleeing mink territory enter unsuitable habitat where they face starvation and exposure. Mink trapping and removal, while lethal to the invasive mink, is considered justified on welfare and conservation grounds given the devastation mink cause to native water vole populations.