The risk of disease and threats to the wild population. Special Issue: Conservation and Management of the Southern Sea Otter

The growth of the southern sea otter population has been steady, but slow in comparison to Alaskan subspecies, and range expansion in California has faltered. Slower growth is occurring in California despite birth rates comparable to those in Alaska, so biologists have reasoned that mortality is hindering the growth of the California population (Riedman and Estes 1990; see Estes et al., this issue). In order to investigate this issue, research efforts have been directed toward identifying the causes of death in southern sea otters.