California sea otters are protected under the Marine Mammal Protection Act, the Endangered Species Act and California state law. But these laws don't protect otters from oil pollution, the greatest threat they face today. Oil tankers travel past the sea otters' home range on a regular basis, and hundreds of tankers ferry crude oil and its products in and out of San Francisco Bay each year. Scientists have calculated that a large spill off San Francisco could foul the otters' whole range with oil. Such a spill would place the entire population in jeopardy.
Sea otters are very vulnerable to oil contamination.
Oil robs an otter's fur of its insulating properties, so most oiled otters die of hypothermia. It can also poison otters if they swallow it while grooming or eating oil-fouled prey. Otters can be cleaned, but the process is very stressful for the animals. Some good did come of the Valdez spill. It fueled the passage of the Federal Oil Pollution Act, which called for the creation of prevention and response teams.