Scientists discover rare, thriving octopus nursery — and maybe a new species

As It Happens6:30Scientists discover rare, thriving octopus nursery — and maybe a new species

Beth Orcutt will never forget the moment she witnessed a baby octopus hatch in the deepsea.

The marine scientist was co-leading a Schmidt Ocean Institute expedition to study the ocean's depths off Costa Rica using a remotely operated vehicle, when her team saw the little mollusk emerge.

They weren't looking for baby octopuses. In fact, until that moment, scientists weren't sure if it was possible for an octopus embryo to survive in such a seemingly inhospitable environment. 

"It was very, very exciting," Orcutt, a senior scientist at the Bigelow Laboratory for Ocean Sciences in Maine, told As It Happens host Nil Köksal. "The whole control room erupted in excitement."

The expedition has confirmed the existence of two healthy octopus nurseries — one in an area called the Dorado Outcrop, and another about 30 nautical miles away — where dozens of females gather together to brood their eggs near hydrothermal vents. 

The findings double the number of octopus nurseries known to scientists, challenge previous assumptions about how the creatures breed, and highlight the importance of underwater vents and seeps to the development of marine life.

What's more, the octopuses breeding off Costa Rica may belong to a previously unidentified species. 

Not so solitary, after all

Zoologist Michael Vecchione, who was not involved in the expedition, says discoveries of octopus nurseries have been controversial in the marine science community.

That's because octopuses, he says, are solitary creatures. They spend most of their lives by themselves, and until about a decade ago, they had only ever been observed brooding and hatching their eggs alone. 

But that narrative was challenged when scientists first came across a group of more than 100 brooding female octopuses at the Dorado Outcrop in 2013. 

At the time, the scientists didn't see any viable embryos in the octopus eggs, and another visit a year later yielded the same results.

"There was some speculation that the octopods had made a terrible mistake, leading them to believe the environment was not suitable for egg development," Vecchione, the curator of cephalopods at the National Museum of Natural History in Washington, D.C., told CBC.

When Orcutt and the expedition team returned to the Dorado Outcrop this year, they expected to find more eggs, but no babies. 

"We were very surprised when we saw not only embryos, but the actual babies being born," she said.

Not only did the team confirm the Dorado Outcrop nursery is healthy and functional, but they also discovered another octopus nursery about 30 nautical miles away.

There are at least two other such nurseries known to scientists — one found on the Davidson Seamount off California in 2018, and another discovered this summer off Canada's west coast.

"I think it's pretty clear now that it's an important reproductive strategy," Vecchione said. 

The nurseries in Costa Rica and California contain members of the genus Muusoctopus.

Orcutt says they were able to collect specimens of the creatures during the recent expedition, and they now suspect the ones at Dorado Outcrop may belong to a previously unrecorded species of Muusoctopus.

If they are right, it will be one of dozens of new species discovered on deepsea expeditions in recent years. 

A source of ocean life 

The nursery in B.C. is located near a cold seep, a fissure on the ocean floor from which hydrogen sulfide, methane and other hydrocarbon-rich fluids and/or gases escape.

The other nurseries are located near hydrothermal vents, fissures on the seabed that discharge water heated by geothermal energy.

"We think that warmer water allows the eggs to develop faster, and that's why the octopus has adapted to live in somewhat of a stressful environment," Orcutt said. 

She noted that just last month, a study revealed that some octopuses and squid cope with the cold by altering their bodies on the molecular level, literally editing their own RNA. 

"We're really learning that octopus have a lot to teach us about how to survive and adapt."

Octopuses aren't the only marine life the expedition found near the vents. Teams in B.C. and Costa Rica also found skate fish nurseries and other ocean critters. 

Verena Tunnicliffe, a marine biologist at the University of Victoria and a Canada research chair in deep ocean research, says these findings highlight the important role underwater vents play in sustaining marine life.

"The vents and seeps sponsor high local productivity that likely makes an attractive nursery ... for hatching octopus and skates to feed," she told CBC in an email.

"These animals are important top predators in the ocean maintaining a balanced food chain. Thus, consideration of the role of conservation measures in maintaining these ecosystems is important."

The Schmidt Ocean Institute says the expedition's Costa Rican scientists are now working to determine whether the vents they studied should be designated as marine protected areas in order to keep them safe from deepsea fishing and mining. 

"You have these really unique organisms clearly having a successful nursery. And if something were to impact those places, you could really damage the ability for that species to survive," Orcutt said. 

The team is heading back to the area in December to explore further — and Orcutt says she's excited to see what they'll discover next.

"I am sure we're going to find some new cool things," she said.