"River otters" refers to a type of animal that lives in rivers and streams. They are small, furry creatures with long bodies, short legs, and webbed feet that help them swim. Full definition
At the lake itself we can enjoy the spectacle of Giant River Otters. (peruvacationtours.com)
[Adi Barocas et al., Coastal latrine sites as social information hubs and drivers of river otter fission — fusion dynamics.] (scientificamerican.com)
Visitors to San Josef Bay will often see river otters and mink in the river and estuary, as well as Canada geese, common merganser and, in the winter, Trumpeter swans. (env.gov.bc.ca)