Scientists Solve Mystery of Why Thousands of Octopus Migrate to Deep-Sea Thermal Springs

In 2018, researchers from NOAA’s Monterey Bay National Marine Sanctuary and Nautilus Live observed thousands of octopus nesting on the deep seafloor off the Central California coast. The discovery of the “Octopus Garden” captured the curiosity of millions of people around the world, including MBARI (Monterey Bay Aquarium Research Institute) scientists. For three years, MBARI and collaborators used high-tech tools to monitor the Octopus Garden and learn exactly why this site is so attractive for deep-sea octopus. In a new study published August 23, 2023 in Science Advances, a team of researchers from MBARI, NOAA's Monterey Bay National Marine Sanctuary, Moss Landing Marine Laboratories, the University of Alaska Fairbanks, the University of New Hampshire, and the Field Museum confirmed that deep-sea octopus migrate to the Octopus Garden to mate and nest. The Octopus Garden is one of a handful of known deep-sea octopus nurseries. At this nursery, warmth from deep-sea thermal springs accelerates the development of octopus eggs. Scientists believe the shorter brooding period increases a hatchling octopus’ odds for survival. The Octopus Garden is the largest known aggregation of octopus on the planet—researchers counted more than 6,000 octopus in a portion of the site and expect there may be 20,000 or more at this nursery. The open-access Science Advances article is titled “Abyssal Hydrothermal Springs—Cryptic Incubators for Brooding Octopus.”