Quirks & Quarks

Spooky Arctic jellyfish surprises scientists in viral video

Why an ancient marine creature was caught on tape dragging its tentacles in the Arctic Ocean

Eerie footage leaves no doubt jellyfish can survive freezing temperatures

Craig Aumack, left, Wes Swenson, centre, and Andrew Juhl with a medusa caught in May 2014 using a net deployed under the Arctic ice. (Miles O’Brian)

Scientists were stunned by the surprising behaviour they captured on film. 

This week, internet viewers got a glimpse, too. 

In a murky, underwater scene, a spooky-looking jellyfish sweeps its tentacles along the icy ocean bottom.

The surprise

The initial discovery only came about through a happy accident. 

It all happened after a gruelling day of digging through thick Arctic ice off Alaska.

Craig Aumack is a Visiting Assistant Professor of Biology at Georgia Southern University. Aumack and his team couldn't believe their eyes when they realized what they'd found.

It was completely fortituous. The researchers had no intention of looking for jellyfish. They were there to study algae that lie in the sea ice. 

A frame of the first Arctic jellyfish video that stunned scientists. (Lamont-Doherty Earth Observatory)

The first video and others fascinated a marine biologist who confirmed the tentacle dragging wasn't a fluke and pinpointed where it was all happening in the water column. 

What might help jellyfish to survive the Arctic winter

The scientists speculate three factors contribute to helping the jellyfish through the winter:

  • Sea ice provides adults some protection against the fierce winter storms.
  • The jellyfish slow down their metabolism in the cold so they don't need as much food during the dark winter.
  • Perhaps the ancient animals drag their tentacles to max out the limited prey down below.

What it means amid massive ice melts 

Over four gruelling winters, Aumack's team showed how the seemingly quiet, icy waters are home to active jellyfish. 

The observations are shifting scientists' understanding of how polar flora and fauna adapt in the warming Arctic ecoystem. 

And while the jellyfish living in the water will likely be ok, biologists warn polar bears and seals that rely on the dwindling ice supply are in a more precarious position.