The Dumbo Octopus: A Graceful Dancer of the Deep Sea

Far beneath the ocean's surface, in a realm of endless darkness, dwells the dumbo octopus (from the genus Grimpoteuthis), a rare sight for human eyes. Those who are fortunate to encounter it are often enchanted by its unique beauty.

This charming octopus, featuring large eyes and distinctive ear-like fins, earned its name from Disney's iconic flying elephant. It's no wonder this internet sensation is hailed as the "world's most adorable octopus."

With their peculiar looks and distinctive features, they stand out as some of the most extraordinary creatures in the ocean.

What Does a Dumbo Octopus Look Like?

The octopus’ translucent, bell-shaped body resembles a gentle phantom floating through the depths. While most measure 8 to 12 inches (20 to 31 cm) in length, a rare 6-foot (1.8-meter) individual has been observed.

Dumbo octopuses feature around 60 suction cups on each arm, perfect for gripping and holding onto their surroundings.

A Family of Umbrella Octopuses

Currently, 17 species of dumbo octopus are recognized, all classified under Grimpoteuthis umbellata, commonly referred to as "umbrella octopuses." (This group also includes Flapjack octopuses.)

By extending their webbed arms, dumbo octopuses can transform into a stunning, umbrella-like shape, captivating anyone who witnesses their display.

Where Does the Dumbo Octopus Live?

This octopus thrives in the deepest parts of the ocean, inhabiting depths between 9,800 and 13,000 feet (3,000 to 4,000 meters), where the water is icy and pitch black. In 2020, two dumbo octopuses were discovered at over 20,000 feet (6,100 meters) in the hadal zone, the deepest region of the ocean.

Researchers on the Five Deeps Expedition observed them in the Java Trench of the Indian Ocean. The team utilized a specialized deep-sea camera, developed by chief scientist Alan Jamieson, PhD, to capture these remarkable images.

Dumbo octopuses have been spotted off the coasts of California and Oregon, in the Gulf of Mexico, and near Australia, New Zealand, Papua New Guinea, and the Philippines. Given their ability to thrive in the largely unexplored deep ocean, they could potentially inhabit waters worldwide.

Thriving Under Pressure

The hadal zone, with water pressure hundreds to over a thousand times greater than at the surface, is a harsh environment where few creatures can survive.

Most animals possess air-filled spaces in their bodies, such as lungs or cranial cavities, which would implode under the immense pressure of the deep ocean.

However, dumbo octopuses are uniquely adapted to withstand such extreme conditions.

"They lack any gas-filled spaces that would be directly impacted," explains Stephanie L. Bush, PhD, of the Smithsonian, whose research on dumbo octopuses is supported by MBARI and the Monterey Bay Aquarium.

Dumbo octopuses are uniquely adapted to deep-sea life. "Their enzymes have evolved over time to function under extreme pressure and cold," notes Dr. Bush. "Human enzymes would fail under such conditions, disrupting essential processes like digestion."

Similar to other octopuses, dumbo octopuses thrive in cold, low-oxygen environments thanks to their copper-based blood.

Ballerinas on the Ocean Floor

Many octopuses, including the dumbo, can employ jet propulsion to evade predators. By drawing seawater into their large mantles and forcefully expelling it, they propel themselves to safety.

The dumbo octopus, however, appears to lack this capability. With minimal predators in the deep ocean, speed is unnecessary. Instead, they compensate with their graceful movements.

Elegantly gliding through the water, the dumbo octopus propels itself by rhythmically opening and closing its eight webbed arms, while its ear-like fins guide its direction.

“Finned octopuses, like the dumbo, spend most of their lives swimming and drifting in the water,” explains Danna Staaf, PhD, a marine biologist and author of "The Lives of Octopuses & Their Relatives: A Natural History of Cephalopods." “In contrast, finless octopuses, often seen in aquariums, primarily crawl along the seafloor.”

Fewer Predators, Fewer Defenses

Most octopuses rely on an ink sac for defense, releasing ink into the water to deter predators or create confusion while they escape.

Dumbo octopuses lack an ink sac. In the deep sea, where predators are scarce, they have no need for such defensive tactics.

Unlike many octopuses that can alter their appearance, dumbo octopuses rarely rely on this ability. "Living in perpetual darkness, they have little need for camouflage," explains Dr. Bush.

Their reddish hue provides a natural advantage, as red light doesn’t penetrate the deep ocean, making them nearly invisible in their environment.

What Does the Dumbo Octopus Eat?

The dumbo octopus likely feeds on oysters, crustaceans, snails, and worms. (The uncertainty stems from the challenges of studying this species in its deep, dark habitat.)

In 2020, Harvard researchers identified sensors in octopus suction cups that seem to help them determine if an object they touch could be edible.

Dumbo octopuses are part of the cirrate group, characterized by spines on their suckers called cirri. These cirri are likely used to guide food toward their mouths.

Challenges of Researching Deep Sea Species

The deepest-living octopus has won many admirers. "I’m biased, but I find them fascinating," admits Dr. Bush. "There’s still so much to learn, which is true for most deep-sea and open-ocean creatures."

Studying the dumbo octopus is challenging due to the extreme pressure and cold of its habitat, which humans cannot endure. "We must bring them to the surface and place them in tanks," explains Dr. Bush. "However, they struggle at the surface because their enzymes are adapted to high pressure and low temperatures."

Currently, numerous companies and nations are exploring deep-sea mining for minerals, a practice Dr. Bush warns could endanger marine species we have yet to study or even discover, such as new octopus varieties.

Scientists are also eager to uncover more about how octopuses function, including the fascinating dumbo octopus.