- North American river otter (Lontra canadensis): 1 to 6 pups
- Eurasian otter (Lutra lutra): 1 to 4 pups
- Spotted-necked otter (Hydrictis maculicollis): 2 to 4 pups
- African clawless otter (Aonyx capensis): 1 to 5 pups
- Giant otter (Pteronura brasiliensis): 1 to 5 pups