Vid A bunch of volcanologists working near the Solomon Islands has turned up a find that left them “freaking out”: a seldom-seen variety of Pacific sleeper shark just about living in a volcano.

The group, working with National Geographic, were studying underwater volcanoes earlier this year when they caught the high-definition footage on a drop-cam about 20 km (12 miles) from the Kavachi volcano.

From 937 metres down, the instrument package's seven hours and 45 minutes of video included what Nat Geo calls a “brown blob”.

The colouring on the animal makes it most likely that what the video shows is a Pacific sleeper shark, a member of a group of slow-moving deep-ocean dwellers that usually favour colder waters – the Northern Atlantic, Northern Pacific, and the waters around Antarctica and Tasmania.

Ocean engineer Brennan Phillips, working for the National Geographic Society under a Waitt grant, says in the YouTube video at the end of the story that “as far as I know, at this point, it's only the third time it's been captured on video”.

Having the sharks living in the volcano's caldera “conflicts with what we know” about the hostile Kavachi environment, Phillips adds.

The video – and its location, outside the usual range of sleeper sharks – could also help resolve a question about whether the sharks are three distinct species, or geographic variants of the one species. ®

Youtube Video