Scientists shocked to find 100 octopus mums in most bizarre of places

18 Apr 2018

An octopus in the genus Muusoctopus travels along a section of sea floor. Image: Phil Torres and Geoff Wheat

Scientists taking part in a deep-sea expedition were shocked to find a group of octopus mothers huddled around a seemingly treacherous place.

We’ve come to expect that there remains so many fantastic and mysterious discoveries left to be made beneath the surface of our oceans, as seen in the recent recording of mating between a male and female anglerfish.

Marine biologists have been shocked once again, with the discovery of a giant group of octopuses and their eggs in a location where, according to what we know, they shouldn’t be able to survive.

‘No, they shouldn’t be there!’

Found more than 3km deep into the ocean far off the coast of Costa Rica, the octopuses were huddling around the cracks of hot water emerging from an underwater volcano.

The investigators from the Field Museum in the US had no intention of searching for animals when they started the mission, instead hoping to simply collect samples of the warm fluid emerging from the cracks.

“When I first saw the photos, I was like, ‘No, they shouldn’t be there!’ Not that deep and not that many of them,” said Janet Voight, author of the study published that detailed the discovery.

From the analysis, the octopus is from an unknown species of the genus Muusoctopus, pink dinner-plate-sized creatures with enormous eyes.

Group shot

Octopuses congregate on the deep-sea Dorado Outcrop; 16 of 17 are in brooding posture. Image: Phil Torres and Geoff Wheat

Based on an estimate, as many as 100 octopuses were observed during the dive, which is very odd given that the Muusoctopus prefers to go solo.

Additionally, almost all of them were mothers clutching on to their eggs and using the hot fluid as a nursery for the young.

As the scientists explained, the sight of so many octopuses in such a location is worrying, given that this is viewed as a potentially suicidal move.

Typically, deep-sea octopus live in cold, invariant temperatures. When exposed to higher temperatures, it jump-starts their metabolism, making them need more oxygen than the warm water can provide.

What else is down there?

By analysing the video footage from the dive, it became clear that the octopuses were in great distress and that the 186 eggs observed showed no signs of developing an embryo.

Thankfully, the scientists believe that the sheer number of octopuses seen in the dive suggests a healthier habitat nearby, such as in the crevices of rocks where the water would be cooler and have bountiful oxygen.

“Never would I have anticipated such a dense cluster of these animals at 3,000 metres depth, and we argue that the numbers of octopuses we see are simply the surplus population,” Voight added. “What else is down there that we can’t even imagine? I want to find out.”

Colm Gorey was a senior journalist with Silicon Republic

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