Sounds Otters Make Otters can be identified by the noises they make. These vocal animals communicate with each other to regulate social behavior. Otter sounds include: A loud "hah!" when startled. Bird-like chirping and humming to signal anxiety or call to another otter. Hissing and growling noises to indicate when an otter feels threatened. Otter Identification Otter sounds are most often heard near rivers, lakes, and marshes. These playful animals are known for their dark brown fur, sleek heads lacking obvious ears, and copious whiskers. Bad Habits While otter sounds can be annoying, they typically point to a bigger problem. When the animals are full, they stop eating and leave the remains of their dinner for someone else to clean up. This can result in odorous fish heads scattered throughout a property. The wildlife experts at Critter Control can safely exclude otters near private homes.