The volcanoes are Pavlof and Cleveland, both in the Aleutian Island range southwest of mainland Alaska.

CNN: 2 Alaska volcanoes on alert as lava flows

Sea otter populations off the Aleutian Islands have dropped by 80-90 percent since the 1970s.

CNN: Oil spill lessons offer hope for sea otters

In 1943, American forces secured the Aleutian island of Attu from the Japanese during World War II.

CNN: News Almanac