Shishaldin Volcano is spewing ash up to 27,000 feet in sky, leading to flight cancelations.
Shishaldin Volcano also erupted last month, sending ash over the Bering Sea.
The pumice blob has the potential to deposit new, healthy coral around the badly damaged Great Barrier Reef, scientists say.
"Since the last eruption event, most seabird species that previously nested on the island have returned and made attempts to breed again...but the habitat is currently not ideal."
Unlike some of its perpetually active neighbors on the Kamchatka Peninsula, Raikoke Volcano on the Kurile Islands rarely erupts. The small, oval-shaped island most recently exploded in 1924 and in 1778.
Shiveluch volcano (Kamchatka) in Kamchata is erupting. Explosive activity continues. Volcanic Ash Advisory Center (VAAC) Tokyo warned about a volcanic ash plume that rose up to estimated 33000 ft (10100 m) altitude or flight level 330 and is moving at 55 kts in S direction.
Ash from Mount Pavlof Lands in Nelson Lagoon