The Wildlife Professional

type and temperature of wash, rinse, and recovery water. This research has also led to physical changes in otter care facilities, such as the addition of industrial-size water softeners and heaters for pools. Although trained captive sea otters such as those used in the trials do not suffer the many stresses and pre-existing health problems of wild sea otters, they do demonstrate what can be done to reduce washing and captivity-related physiologic stress, reduce caloric needs, and shorten the time required for fur to recover its water repellency. Improved recovery times should also shorten overall holding time, thereby decreasing costs and increasing the numbers of otters that can be cared for during a crisis.

Test Case for Science

In February 2009 these new methods got an unexpected trial run. The Monterey Bay Aquarium received a sub-adult female southern sea otter tarred over 50 percent of her body with Monterey formation crude oil (see sidebar). After being medically stabilized and transferred to CDFG, the otter received the kind of care and treatment used during the research trials. Because she was seriously emaciated and rapidly losing body heat, her rinse temperature was increased to 100 degrees F and warm, soft-water pool temperatures were increased to 88 degrees F. The otter (nicknamed Olive) responded as well as the research otters, which had been in excellent body condition. After 53 hours in contact with warm, soft fresh-water pools that were progressively cooled over several days, Olive had regained about 90 percent of her waterproofing and her core temperature was stable. Caregivers used infrared thermography to closely follow improvements in Olive’s coat. The overall cost for care was about $5,000, considerably less than what it cost in 1980. A celebrity test case, Olive gained fans on Facebook, which followed her progress.

Beyond improvements in washing techniques, in the last 20 years researchers have also defined baseline health of otters and improved anesthesia, blood gas monitoring, and treatment of infections, all of which improve chances of survival. We now know, for example, that low doses of fentanyl (0.22 to 0.33 milligrams per kilogram) combined with midazolam and reversed with naltrexone will anesthetize an otter sufficiently for cleaning with minimal side effects and a reduced incidence of seizures, cyanosis, or renarcotization

(Monson et al. 2001). Small, accurate hand-held pulse oxymeters now allow constant monitoring of an otter’s vital signs and oxygen saturation.

The Story of Olive

on february 21, 2009, a female sea otter coated in tar
washed ashore at sunset state Beach on Monterey Bay.
rescued and taken to the California Department of fish
and Game’s Marine wildlife Veterinary Care and research
Center (MwVCrC) in santa
Cruz, the otter needed urgent
care, and became a test case
for science.
After using olive oil to make
the tar soluble enough to wash
out, staff nicknamed the otter
“olive.” They then began treat-
ing her with the new washing
techniques developed by
MwVCrC veterinarian David
Jessup and his colleagues.
The team anesthetized olive
and meticulously washed her
with dishwashing liquid and
warm soft water to remove tar,
soap, and salt, any of which
could prevent the fur from
recovering its ability to trap air
for insulation. They used high-
powered, warm-air dryers on
the pelt, then revived the otter
and released her into a pool
of warm, fresh water that was
gradually cooled.

After about six weeks in recovery on a high-calorie diet of prawns, clams, and abalone, olive appeared healthy enough to earn her release into the wild. with much fanfare she was set free near the spot where she was found on April 7, 2009, 20 years after the exxon Valdez oil spill.

A team from the Monterey Bay Aquarium still tracks olive’s movements through a temperature-sensitive radio implanted in her abdomen. eating and mating normally, olive marks a success for science, and hope for the roughly 2,800 threatened California sea otters that still