Sharks found alive and swimming inside an active volcano

Think you’re handling the summer heat well? Think again. Researchers just uncovered fish, jellies and sharks living inside an active underwater volcano.

When Ocean Engineer Brennan Phillips came across Kavachi, an active underwater volcano in the South Pacific’s Solomon Islands, he knew he’d found an ecological goldmine. Phillips, whose specialty is deep-sea robotics, is always looking for a project that is the best of both worlds—a great science question and a fantastic story.

‘There was amazingly little out scientifically about Kavachi, but plenty of stories about how active it was, and its precedent for making small islands,’ says Phillips. ‘And a big passion of mine is helping negotiate the waters of deep-sea mining, by using detailed information to force officials or companies to want to take the precautionary approach.’

And the Solomon Islands could really use more people like Phillips’ right now. The chain of 992 islands northeast of Australia has recently opened the metaphorical floodgates to logging and mining companies, and as one of the poorest countries in the region, Phillips explains this leads to major oversights. The country is also still pretty young, only gaining autonomy from Britain back in 1978, so realistically, has neither the funding nor time to make sustainable guidelines for these environmentally risky pursuits. Watching pristine forests being clear-cut from their boat, Phillips says his mission became clear.

‘Better understanding the geology and biology of Kavachi became my goal,’ he says. ‘I hoped my work could serve as an example for these type of considerations, or at least a start.’

Phillips got the support of his home institution, The University of Rhode Island, and National Geographic Waitt Grants Program funding, which provided equipment able to handle the volcano’s intense heat and harsh chemical composition while still capturing sharable footage. The most crucial of these fancy tools, says Phillips, was the DropCam, a NatGeo team original—basically a giant glass ball protecting a DSLR camera and programmable computer.

Two species of shark were filmed in the underwater crater of the active Kavachi volcano. The footage was taken at a depth of 45 metres and scientists are astounded at how the creatures can thrive in such environments. Credit: National Geographic
Two species of shark were filmed in the underwater crater of the active Kavachi volcano. Credit: National Geographic

Last January when Phillips and his team set out to chronicle Kavachi his instinct’s started paying off. First they spotted a species of sleeper shark about 20km from the volcano, the southernmost sighting of this animal ever made. Then in July the team really hit the jackpot.

‘When we were finally able to approach the dead centre of the volcano, and toss the DropCam into it, we were all blown away,’ says Phillips, clearly still excited.

Housed within the 200 to 300m wide caldera were smaller to mid-sized fish, tiny jellyfish, and two top predators—a species of hammerhead and silky shark. And this wasn’t a fleeting flow of life either, with animals dipping in and out. This community seemed to inhabit the volcano.

‘I’m still rather amazed,’ says Phillips. ‘A fellow diver got skin burns just getting close to the site. I even questioned whether we should bait the DropCam like we normally do—we simply didn’t expect substantial life, if any.’

Phillips says given how little is known about the volcano, and our ocean’s great depths on a whole, this could be just the tip of the inverted-iceberg. Next the team hopes to determine Kavachi’s acidity, chemical composition, and temperature. They’re also eager to explore just how these animals are able to exist in such conditions. Phillips says there’s long been evidence of flourishing bacterial and fish life around thermal vents, but the community at Kavachi is a novel situation.

‘What’s next?’ says Phillips. ‘I think it’s safe to say only Kavachi knows that.’