animal Type
Maximum Size

14 cm

(6 inches) mantle length


1,200–3,900 m

(3,900–12,800 feet)



including muddy plains, seamounts, and thermal springs


Fishes, invertebrates, and scavenged carrion


Northeastern Pacific Ocean

Oregon to Baja California


Warm springs make an ideal nursery for this octopus mom.

Life in the frigid waters of the deep sea moves at a slow pace. Animals that live in the ocean’s depths often grow more slowly than their counterparts near the surface. A female deep-sea octopus might wait several years for her eggs to hatch, increasing the risk that her offspring may not survive to hatching.

The pearl octopus (Muusoctopus robustus) has a clever strategy to beat the odds. Muusoctopus gather at deep-sea thermal springs to mate and nest. The warm water seeping from the seafloor accelerates the development of octopus embryos.

Scientists have discovered a handful of deep-sea octopus nurseries across the Eastern Pacific, including one in our own backyard. Davidson Seamount is an inactive underwater volcano off the coast of Central California, about 130 kilometers (80 miles) southwest of Monterey. Near the base of the seamount, cracks and crevices bathed in warm water from hydrothermal springs are filled with purple “pearls”—Muusoctopus moms. Welcome to the Octopus Garden, the largest known aggregation of octopus on Earth.

After a mother Muusoctopus attaches her eggs to a rocky ledge, she turns herself upside down, inverts her arms, and shields her developing offspring with her body. As with many other octopuses and squids, a Muusoctopus mom sacrifices herself for her offspring. For nearly two years, she lives off her food reserves, then dies once her eggs hatch.

The Octopus Garden teems with life. Cusk eels, rattail fishes, and other scavengers gather here to feed on the remains of nesting octopus. Sea anemones and snails feast on the remains of dead octopus parents too. Small invertebrates live alongside nesting females, undoubtedly benefiting from unhatched eggs.

Davidson Seamount and the Octopus Garden are protected as part of Monterey Bay National Marine Sanctuary. But other deep-sea oases—including those we have yet to discover—remain at risk from threats like overfishing, pollution, climate change, and mining. 

We can be a powerful ally for the unique animals and environments that lie out of sight deep beneath the ocean’s surface. Help us spread the word about safeguarding the ocean’s pristine wilderness. The future of our big blue backyard depends on us.


Video Clips


Barry, J.P., S.Y. Litvin, A. DeVogelaere, D.W. Caress, C.F. Lovera, A.S. Kahn, E.J. Burton, C. King, J.B. Paduan, C.G. Wheat, F. Girard, S. Sudek, A.M. Hartwell, A.D. Sherman, P.R. McGill, A. Schnittger, J.R. Voight, and E.J. Martin. 2023. Abyssal hydrothermal springs—Cryptic incubators for brooding octopus. Science Advances, 9(34): 1–13.

Drazen, J.C., S.K. Goffredi, B. Schlining, and D.S. Stakes. 2003. Aggregations of Egg-Brooding Deep-Sea Fish and Cephalopods on the Gorda Escarpment: a Reproductive Hot Spot. The Biological Bulletin, 205: 1–7.