Octopuses are known as some of the most intelligent creatures in the ocean, but they are also famous for one more trait they prefer to live alone. That belief is now being challenged after scientists uncovered the world’s largest known gathering of octopuses deep beneath the Pacific Ocean.
The discovery was made nearly two miles below the surface, close to an underwater volcano off the coast of Monterey, California. The site, now called the Octopus Garden, is spread across an area comparable to 233 soccer fields and is believed to host up to 20,000 octopuses.
From solitary hunters to unexpected neighbours
The idea that octopuses could live close to one another first surprised scientists more than a decade ago. In 2012, researchers diving near Jervis Bay in Australia stumbled upon a mound of shells occupied by multiple gloomy octopuses. The animals were not just sharing space but interacting with each other.
Soon after, another nearby site was found where octopuses were seen mating, fighting, communicating and even forcing rivals out of dens. These places, later named Octopolis and Octlantis, hinted that octopus behaviour might be more complex than once believed.
Still, nothing prepared scientists for what they would find in the deep sea.
Massive deep-sea nursery hidden in the dark
In 2018, researchers from the Monterey Bay Aquarium Research Institute discovered a vast nursery of pearl octopuses Muusoctopus robustus near an underwater volcano. Thousands of female octopuses were found nestled into rocky crevices, each guarding a clutch of eggs.
Scientists counted more than 6,000 individuals directly, but detailed surveys suggest the total number could reach 20,000. From a distance, the octopuses resemble clusters of shimmering pearls scattered across the ocean floor.
This makes the Octopus Garden the largest octopus aggregation ever recorded anywhere in the world.
Warm waters give eggs a fighting chance
The secret behind this gathering lies in heat. While deep-sea waters are usually freezing at around 1.6 degrees Celsius, the rocky nests in the Octopus Garden are warmed by hydrothermal springs, reaching close to 11 degrees Celsius.
The warmer environment allows octopus eggs to develop and hatch much faster. This is critical because octopus mothers die shortly after their eggs hatch. Faster hatching reduces the time embryos are exposed to predators, dramatically improving their chances of survival.
Scientists say the discovery has reshaped understanding of octopus life in the deep ocean, proving that even creatures known for solitude can come together when survival depends on it.