Assessment of Post Wash Pelage

How do you know when a sea otter’s pelage has been fully restored? We know that sea otter’s rely on a unique form of thermal insulation among marine mammals. After being oiled and then washed, the natural oils that prevent the hairs from tangling and getting fouled with salts are washed away along with the oil.

The dense fur that allows sea otters to stay warm in water is completely compromised for days to weeks after oiling and thus, the animal is at risk for hypothermia. Infrared thermography is one tool that has proven very useful in helping husbandry and veterinary personnel determine when the natural oils have fully returned and the pelage of an animal is providing a normal insulation barrier. Below you will see infrared images of sea otters after being washed and with normal coats. Can you tell without looking at the caption which animals have been recently washed?