River otter populations have recovered significantly in many regions following pollution reduction. Their welfare today is maintained by clean water, fish populations, and appropriate habitat along waterways.
River otter welfare recovery is one of the success stories of wildlife conservation — populations that were functionally extinct from pollution and overtrapping have been restored through regulatory action and where needed, reintroduction. The welfare of reintroduced animals involves capture and transport stress from donor populations, followed by territory establishment in unfamiliar rivers. Surviving individuals benefit from improved water quality providing abundant fish prey in clean, structurally complex rivers. Road mortality at river crossings continues to cause traumatic deaths, and wildlife crossing infrastructure at road-river intersections reduces this preventable welfare harm. Monitoring otter populations as indicator species provides ecosystem health information that also informs welfare management.