Excerpt from Marianne L. Riedman and James A. Estes, The Sea Otter (Enhydra lutris): Behavior, Ecology, and Natural History. Washington, DC: U.S. Fish and Wildlife Service, 1990: 68.
A female invests considerable resources in caring for her pup, which is dependent on her for nourishment, grooming, and protection, especially when young. According to Sandegren et al. (1973), mothers nurse their pups an average of six times per day (during daylight) with each nursing bout averaging 9 min. Females with pups at Point Lobos, California, spent 41% of their daylight hours resting, 16% feeding, 20% grooming their pup, 10% grooming themselves, 13% swimming, and 8% nursing their pup (which was always done in conjunction with resting, swimming, or grooming of the pup)….
While pups are young, females remain with their pups constantly unless the mother is diving for food.