Sea otters were widely extirpated for their fur, dramatically reducing their genetic diversity. This, coupled with a variety of environmental disturbances, has threatened sea otter populations throughout their range. We are collaborating with Shawn Larson of the Seattle Aquarium to investigate this problem using stress, reproductive and genetic measures in wild and captive sea otters. Fecal estrogen and progesterone analyses have clarified reproductive seasonality, estrus cycle length, induced ovulation, and delayed implantation in captive sea otters.

Increased stress hormone levels are associated with low genetic heterozygosity (He), low growth rate (GR), and high population densities in wild sea otters. This study is being expanded to include additional sea otter populations, and we expect results to improve management of both wild and captive populations.