Eurasian otters have recovered significantly since organochlorine bans, but river quality and habitat availability continue to determine individual otter welfare outcomes in ways that make river restoration a welfare intervention.
Otters living in degraded river systems face chronic food insecurity as fish populations decline with water quality. Individual otters in poor habitat have smaller, lower-quality territories that require more energy to defend and exploit. Road mortality is the most acute welfare problem — otters killed on roads die violently, often at river crossings where culverts force them to surface. River restoration creates the ecological conditions for otter welfare — clean water, abundant fish, secure holts, and safe movement.