Dumbo octopuses live in the deep open ocean down to depths of at least 13,100 feet (4000 m) and perhaps much deeper, making this group the deepest living of all known octopuses. Life at these extreme depths requires the ability to live in very cold water and in the complete absence of sunlight. Dumbo octopuses are naturally rare, and the deep sea is enormous, so these species have specialized behaviors to increase the likelihood that they can successfully reproduce anytime that they find a mate. Females apparently always carry eggs in different stages of development, and they are able to store sperm for long periods of time after mating with a male. Using these advantages, female dumbo octopuses can transfer sperm to their most developed eggs any time the environmental conditions are right for reproducing. Though they spend much of their lives suspended above the seafloor, dumbo octopuses lay their eggs on the bottom, attached to rocks or other hard surfaces.

Dumbo octopuses move by slowly flapping their ear-like fins, and they use their arms to steer. They are foraging predators and eat pelagic invertebrates that swim above the sea floor. As there are few large predators in the deep sea, dumbo octopuses’ primary predators are diving fishes and marine mammals, including tunas, sharks, and dolphins. Due to their preference for extreme depths, they are only very rarely captured in fishing nets and are probably not threatened by human activities.

Fun Facts About Dumbo Octopuses

1. The Dumbo octopus is named after Disney’s Dumbo the elephant character, from the eponymous movie, that was famous for its big ears.

2. Unlike most octopuses, the Dumbo octopus doesn’t have an ink sac because it rarely encounters predators in the deep sea.

3. The Dumbo octopus uses its ear-like fins to propel through the water and steers using its webbed arms.1

4. The Dumbo octopus is the deepest-living genus of all known octopuses. It lives at least 13,100 feet (4,000 m) below the surface.

5. The largest Dumbo octopus ever recorded was 5 feet 10 inches (1.8 m) long and weighed 13 pounds (5.9 kg), but most species are an average size of 7.9 to 12 inches (20-30 cm) long.2

Engage Youth with Sailors for the Sea

Oceana joined forces with Sailors for the Sea, an ocean conservation organization dedicated to educating and engaging the world’s boating community. Sailors for the Sea developed the KELP (Kids Environmental Lesson Plans) program to create the next generation of ocean stewards. Click here or below to download hands-on marine science activities for kids.

References:

1 The MarineBio Conservation Society

2 Aquarium of the Pacific