From The Ashes: Life Returns To Kasatochi Volcano

Feb 14, 2017

 

Two months after the eruption, Kasatochi Island looked like the moon.
Credit Courtesy Jerry Morris

The news may sound familiar: There’s a volcano erupting in the Aleutian chain that’s a refuge for marine mammals and sea birds. But it isn’t Bogoslof, it’s Kasatochi — a volcano near Adak that erupted for the first time in modern memory in 2008. That eruption has given scientists the opportunity to study how life returns after cataclysmic destruction.

Kasatochi Island was an inactive volcano. It wasn’t supposed to erupt.

“That’s one of the reasons why we picked it to study seabirds each year,” said Steve Delehanty. He’s manages the Alaska Maritime Wildlife Refuge which includes Kasatochi. “We went out and studied them each year for many years and had a tiny little primitive cabin on the island where people stayed.”

Back in 2008, two biologists were living on Kasatochi for the summer studying the island’s auklet colony. In early August, they started feeling tremors. A few days later, the Alaska Volcano Observatory recommended they evacuate. The biologists escaped in a boat less than 30 minutes before the volcano violently erupted. Remember that cabin? It vanished.

The eruption also obliterated the rich ecosystem of Kasatochi, burying the once lush island in feet of ash.

“We didn’t know if there was a single living thing left on this island,” Delehanty said.

Delehanty says there were no detailed studies in Alaska of how ecosystems respond to volcanic eruptions like Kasatochi’s. So, the refuge formed a team of scientists, from geologists to biologists, to keep tabs on the island’s recovery.

Derek Sikes is part of that team. He’s an entomologist – he studies bugs – at the University of Alaska Fairbanks.

He happened to visit Kasatochi two months before the eruption. When he heard about the opportunity to go back, his first thought was drudgery. He didn’t want to devote time to documenting a lifeless island.

“I didn’t really find the idea of hiking around a lot of mud and ash for years to be very appealing,” Sikes said. “I expected there to be nothing interesting entomologically for a long time. I was however pleasantly surprised.”

He took his first trip back about a year after the eruption. And he found life on the island – including bugs.

“So there were definitely some survivors but the plants were not numerous enough to support insect populations, so all the insects were surviving off of matter on the beaches,” Sikes said.

Organic matter like kelp, driftwood, and dead fish. That was really interesting to Sikes because textbook ecology says new ecosystems start with plants. Definitely not bugs.

He did some research and found more exceptions to the rule. Places like Mount Saint Helens and Krakatoa — where melting glaciers reveal barren land primed to be recolonized — also had this unusual structure.

“Kasatochi became another chapter, another bit of evidence, in this exception to the rule that plants are always the first and most interesting things that establish in a new ecosystem,” Sikes said.

Nearly a decade after the eruption, life is slowly returning to Kasatochi. But it still looks a lot like the moon. Sikes has found just as many types of bugs post-eruption as he found before. But he’s documenting different species. He doesn’t know if that’s because his previous list was incomplete, because new bugs are hitching rides to Kasatochi, or some combination of both.

“We go back there every year and we want to be able to compare the growth of this ecosystem to other islands in the Aleutians, but no other island in the Aleutians has been as well studied as Kasatochi,” Sikes said. “Our ignorance of the biodiversity is pretty large.”

There’s no going back in time. But with Bogoslof Island erupting, Delehanty says scientists have another opportunity to study life’s return in a pristine natural laboratory.

“I think what we can take from Kasatochi is an appreciation that patches that might be filled with ash on Bogoslof aren’t necessarily devoid of life,” Delehanty said. “That this resilience of life might express itself on Bogoslof as well.”

That said, Delehanty cautions scientists won’t know what’s there until they can visit the island. Assuming it’s safe, the Fish and Wildlife Service is planning a trip to Bogoslof this summer.