Water voles have suffered a 97% population decline in the UK, the fastest decline of any UK mammal. American mink, introduced for fur farming, prey on water voles devastatingly effectively. Mink control programs are essential for water vole recovery.
Water voles in systems with uncontrolled mink populations face systematic predation of entire colonies. A single mink can eliminate a water vole colony in days. Individual water voles pursued by mink experience acute fear and die rapidly through predation. Mink control creates a welfare conflict: humane dispatch of invasive mink enables the welfare improvement of thousands of water voles. The scale of benefit to water voles significantly outweighs the welfare cost of managed mink control.