In western Uganda, hippos move between land and the Kazinga Channel, making them ideal sentinels of ecosystem health. By testing hippo dung and using environmental DNA, we can detect pollutants and pathogens moving through the watershed. Over 60,000 people depend on these waters for food, making this a critical One Health issue. We hypothesize that higher levels of pollutants and pathogens will be detected in hippos, soil and waters near areas of higher human activity.