After Close And Tireless Observations By Scientists, This Octopus Finally Reveals What It Was Guarding

Octopi are some of the most fascinating animals on the planet. Not only are they highly intelligent, but they also show strange and unknowable behavior. A group of scientists watched a mysterious deep-sea octopus sit motionless for just over half a decade, only to discover that it was standing watch over an unexpected hoard of objects. 

As well as having incredible eyesight, octopi are well known for their great intellect. They have a complex nervous system and can readily learn and adapt to their environment like humans. Most researchers who study them remark on their eerie levels of awareness.

For a quarter of a century, researchers at the Monterey Bay Aquarium Research Institute have spent their lives understanding deep-sea animals. The non-profit institute, located in Moss Landing, California, performs cutting-edge marine research with the help of high-tech tools, such as robotic underwater vehicles.

Over 25 years, teams of institute researchers led investigations into a part of the ocean floor that the Institute called Midwater 1—a canyon-shaped underwater landscape filled with intriguing flora and fauna. It was an exciting venture because it was previously unmapped.

In May 2007, one of the Institute’s remotely operated vehicles was sent to the depths of Midwater-1 to comb the deepest (and most difficult-to-explore) areas. The latest technology of the vehicle shed light on long-unseen mysteries deep below.

Bruce Robison – the project’s team leader – caught a glimpse of something hanging over a ledge in the watery canyon from the screen. The vehicle was commanded to move closer to investigate. They saw the striking outline of what looked to be an octopus clinging to the rock.

The team was transfixed with the creature. After a long time, the octopus stirred, slowly moving one of its tentacles away from the rock face. It was very much alive. It isn’t always easy capturing footage of an octopus, but this one seemed like it was sitting in for the long haul.

Octopuses have been around for over 300 million years and are related to squids and cuttlefish. They started as small, shelled creatures and evolved to become more agile and intelligent, with advanced nervous systems and eyes like those of vertebrates.

As well as being able to hide at will, they also have powerful deterrents. Upon seeing a foe, they can shoot jets of ink or poison. Bruce and his team had to be careful not to annoy their octopus with their vehicle, lest it strike out!

Although intelligent animals, octopi do not possess long lifespans and only live around one to two years at a time. While an octopus needs little time to adjust once it hatches, its time is limited. Not only that, but once they mate, their time is up.

With their prickly demeanor and short lifespan in mind, it’s no wonder that the team at the Institute was puzzled by this still female clinging to the rock as it did once they returned with the remotely operated vehicle on their second trip a month later.

The researchers were baffled. Upon repeat visits, they always found her in the same position. She was alive and appeared to be resting, but there had been no signs of movement. The researchers looked back to their previous tapes and confirmed it.

If she was sick, she took her time to heal (or succumb). The researchers also played around with another idea: she was hiding something. She splayed herself out like she was trying to cover something up. What would an octopus want to hide?

As intriguing as this one mysterious octopus was, the team still had a job to do. They surveyed the rest of the area, and just as they were about to bring their remotely operated vehicle to the surface, they checked back in. Of course, she was still there. 

Most types of octopi prefer a habitat closer to the ocean floor. They hunt for food closer to the surface but make their homes in places they can sneak around and hide in, like flooded caves, crevices, and under the natural cover of darkness.

It had been over a month. After noticing she had become thinner, the scientists brought a gift down with the remote vehicle to see if she would move from hunger. They presented her with crab meat, but she didn’t seem interested. The next time they saw her, they met her in person.

The divers from the Institute inspected her limbs and head. They were looking for signs of motor damage or potentially a movement-impairing wound that kept her fastened to the ledge, slowly starving. But they couldn’t find anything out of the ordinary. 

The researchers at the Institute played this game with her for months. Each time they went down into Midwater-1, they checked for signs of movement but found no evidence. How was this octopus even still alive?

Midwater-1 produced types of animals—octopi in particular—that humans hadn’t seen before. But was there something about the area that had attracted this octopus? Perhaps a reliable source of food? Could it be that the octopus would suddenly feast on a hearty meal, then return to rest? 

The researchers at the Institute were quick to point out that octopi are not known for their meager appetites. An octopus will eat about anything it can catch, including lobsters, small fish, crabs, clams, mussels, and snails—you name it. 

As well as something expanding beneath her, the divers noticed the softer parts of the cliff had changed. She had dug herself in but was sitting on (or against) something large. At this point, the researchers were sure they knew what she was doing. 

The team realized that she had been guarding the most valuable treasure an octopus could have—all 150+ of them. Her behavior was strange to those humans who had only ever known about a fraction of the sea’s mysteries. The answer was simple but incredible all the same.

If the researchers “couldn’t wait” for those eggs to hatch, they would be on tenterhooks for quite some time. For 53 months, this female octopus sat on her eggs, protecting them, while she slowly withered away. The eggs grew larger under her care. And — there were lots of them.

Bruce and the other researchers guessed that she had been able to watch over her eggs for so long because she hadn’t moved, lowering her metabolism and need for food. Whatever the case, it seemed to have worked. 

Within this headstrong, unwavering octopus pumped the heart of a dedicated mother—or three hearts. Because they live in such cold places with such low oxygen levels, octopi need all three of their hearts pumping blood cells around their elongated limbs and body.

Her three hearts were all in the right place. Since all octopi have a central brain and then a brain for the working of each tentacle, it appeared that she had her minds made up—she would protect her babies for the rest of her life. 

Bruce and the researchers were floored by her brooding time, which he described as going “on and on.” The eggs finally hatched in September 2011. One reason for the eggs’ slow development—and their mother’s long deterioration and stamina—was the cold temperature down at that depth.

“We tend to think of parental care only in higher life forms,” Bruce said concerning her extreme level of dedication, “but here’s a parent who is going all out to ensure the survival of her offspring.” If starving yourself for four years and six months doesn’t prove that, nothing does.

Once her watch over her eggs was done, she finally left the ledge and passed on into the dark. The Graneledone boreopacifica eggs, which were sealed in fresh, oxygen-rich water by their mother, swam into their watery world, fully formed and ready to hunt. They were large for octopi.

The mother octopus didn’t look in good shape the last time Bruce or any of the researchers at the Institute saw her, but she did successfully fulfill what seemed to be her life’s task. Her legacy goes swimming in a hundred and sixty little (or big) ways.