Eurasian and North American river otters have recovered substantially after persecution and pollution, but face new challenges including pollution, road mortality, and fisheries conflict.
Otter welfare at population level reflects the success of conservation interventions removing primary threats. The recovery of Eurasian and North American otter populations following hunting bans and pesticide restrictions demonstrates that welfare at scale can be improved through policy action. However, new welfare threats have emerged as populations expand into fragmented landscapes. Road mortality, particularly at river crossings near busy roads, causes significant deaths — each individual lost represents acute suffering from vehicle collision trauma. Wildlife bridges and underpasses at known crossing points significantly reduce road mortality and are cost-effective welfare investments. Fisheries conflict leads to illegal persecution in some areas, with traps set by fish farm operators causing drowning deaths. Pollution from agricultural runoff and pharmaceutical contamination continues to affect health and reproductive success in many river systems. Otter welfare is inseparable from freshwater ecosystem health — clean rivers with abundant fish populations support otter welfare at landscape scale.