The phrase “this place is a pigsty” might need to be replaced with “this place is an otter latrine.” Particularly the busy latrine of a North American river otter (Lontra canadensis). The wildlife cameras in the area eventually spotted a river otter defecating on the dock. Otter scat on a wooden marsh overlook at the Smithsonian Environmental Research Center. Ecosystem engineers and ‘disease sentinels’The presence of parasites in the otter scat could mean that they are important ecosystem engineers. “Some of the parasites that infect river otters could potentially also infect humans, who also are mammals,” Lohan concluded.