Octopus ‘City’ Found Off the Coast of Australia

Expected to live as loners, gloomy octopuses may actually live in groups bustling with activity

Octopus City
A gloomy octopus among piles of discarded shells at Octlantis Peter Godfrey-Smith

In the waters of Jervis Bay, just off the coast of eastern Australia, lies a city bustling with life—octopus life, that is.

As Ephrat Livni writes for Quartzresearchers found an octopus "city" composed of 15 of the eight-legged beasts known as "gloomy" octopuses, which go by the scientific name Octopus tetricus​. Researchers have long thought that this species of octopus is antisocial—save for the rare interactions to mate. But a new find is changing the way scientists think about the eight-legged mollusks.

Over the course of eight days of observation, the researchers watched as the bevy of gloomy octopusesmated, communicated, fought and more at the site they dubbed "Octlantis," ​writes Yasmin Tayag for Inverse. The octopuses even "evicted" each other from dens at the site, which the creatures often sculpted from the leftover shells of prey. Much like the stereotype of the agitated New Yorker, it appears that the crowded conditions of the city led to tension. The researchers published their findings earlier this month in the journal Marine and Freshwater Behaviour and Physiology

This isn't the first such octopus city discovered by scientists, writes Rachel Feltman for Popular Science. In 2009, one of the researchers in this group discovered a site dubbed "Octopolis" fairly close to Octlantis with a similar social arrangement among the gloomy octopuses.

These new finds give insights into the lives of the mysterious octopus—a creature that is notoriously difficult to study, the researchers tell Feltman. Masters of disguise, it is difficult (and expensive) to track down the animals in the wild. And they're even harder to keep in labs. Not only are they particular about their tank chemistry, the researchers tell Feltman, they are the ultimate escape artists.

Despite these challenges, past researchers have managed to study the beasts. These studies have suggested that like other octopuses, the species appears to be fairly intelligent. A 2010 study using a few captured gloomy octopuses even found that the animals appeared to have different personalities, like some people do.

But there's still much to be learned about octopus cities. Why did octopuses group together? The creatures would presumably have more free reign over food and space living alone, Tayag writes. But one reason to group up could be defense. Many others animals group together to defend the group or cooperate in certain ways. One example is fish swimming together in schools, which allow them to not only stave off predators but also swim more efficiently. It could also be that the region of octopus settlements have plentiful food but limited shelter, forcing them to live in close quarters, notes Livni.

The researchers hope to answer these questions by continuing their study of the octopus settlements. But in the meantime, you might want to hold off on moving in.

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