ALLOZYMIC VARIATION IN CALIFORNIA SEA OTTERS

A survey of electrophoretic variation was conducted using 74 sea otter s from California and nine from Alaska. Thirty-one presumptive loci we re successfully scored. Because of the severe bottleneck suffered by t he population in California, we compared the level of genetic variatio n in this population with otters from Alaska. For both samples, 19.4% of loci studied were polymorphic with two alleles each, and heterozygo sity was 4.9% (7.4% based on Hardy-Weinberg expectations). Sea otters show genetic variability levels more typical of terrestrial mammals th an marine species. Comparing samples from California and Alaska, allel ic and genotypic frequencies differed at one locus and heterozygosity levels were 2.2% greater in the sample from Alaska. At three loci, sea otters from California had a deficiency of heterozygotes. Local inbre eding seems to be the most likely explanation for this deficiency. Our results support the predictions of earlier models that otters from Ca lifornia suffered only a small loss in genetic variability.