The water vole has suffered the most dramatic decline of any UK mammal, losing around 90% of its population since the 1970s. Its recovery depends on tackling invasive American mink and restoring riverside habitat.
Water vole welfare is dominated by the threat of mink predation. The speed and totality of mink predation on water vole colonies means that entire social groups can be eliminated within days. Individual voles experience acute stress and predation death. Conservation interventions using mink trapping are welfare-positive for water voles but require honest acknowledgment of the welfare implications for trapped mink. The longer-term hope is that recovering otter populations will naturally suppress mink and provide sustained protection for water voles without requiring permanent human-managed trapping programmes.