Sea otter research methods and tools

Sea otters possess physical characteristics and life history attributes that provide both opportunity and constraint to their study. Because of their relatively limited diving ability they occur in nearshore marine habitats that are usually viewable from shore, allowing direct observation of most behaviors. Because sea otters live nearshore and forage on benthic invertebrates, foraging success and diet are easily measured. Because they rely almost exclusively on their pelage for insulation, which requires frequent grooming, successful application of external tags or instruments has been limited to attachments in the interdigital webbing of the hind flippers. Techniques to surgically implant instruments into the intraperitoneal cavity are well developed and routinely applied. Because they have relatively small home ranges and rest in predictable areas, they can be recaptured with some predictability using closed-circuit scuba diving technology. The purpose of this summary is to identify some of the approaches, methods, and tools that are currently engaged for the study of sea otters, and to suggest potential avenues for applying advancing technologies.