Scientists have reportedly solved the mystery of the “Octopus Garden,” a large congregation of octopuses off the coast of California, considered to be the largest gathering of such creatures on the planet.
Researchers from the National Oceanic and Atmospheric Administration’s Monterey Bay National Marine Sanctuary first documented the gathering in October 2018. The garden is located on the ocean floor about two miles below the surface near Davidson Seamount, an extinct underwater volcano 80 miles off the coast of Monterey, California.
Scientists documented thousands of Muusoctopus robustus nesting on the sea floor near hydrothermal springs. Some of the creatures have been sitting on their nests for years at a time.
Researchers documented over 6,000 octopuses in just one part of the site, however, they suspect there could be more than 20,000 present in total.
In the years since the discovery, scientists have been puzzled as to why this particular species of octopus gathers at the location in such large numbers. After about three years of research, scientists said they think they have the answer.
A new study led by Monterey Bay Aquarium Research Institute’s (MBARI) senior scientist Jim Barry revealed that the creatures migrate to the location exclusively to nest and mate. The warmer water that results from the hydrothermal vents allegedly plays a part in increasing the survival odds of their young.
Researchers said they believe that warm water coming from the springs “accelerates” the development of the octopuses’ eggs, which leads to a shorter brooding period.
They reached such a conclusion after 14 dives using the MBARI’s remotely operated vehicle, which has been dubbed Doc Ricketts.
Scientists expected that the eggs would hatch within five to eight years due to the freezing temperatures of the water. However, to their surprise, the eggs were observed hatching within only two years.
They said they believe that the warm water from the springs boosts the “reproductive success” of the species by accelerating the metabolism of female octopuses and their offspring, allowing them to develop faster and decreasing the odds of them being killed by a predator.
“The deep sea is one of the most challenging environments on Earth, yet animals have evolved clever ways to cope with frigid temperatures, perpetual darkness, and extreme pressure,” said Barry, according to a press release. “Very long brooding periods increase the likelihood that a mother’s eggs won’t survive. By nesting at hydrothermal springs, octopus moms give their offspring a leg up.”
Barry claimed the location is an “essential biological hotspot” that must be protected from fishing, mining, and climate change.
“Protecting the unique environments where deep-sea animals gather to feed or reproduce is critical, and MBARI’s research is providing the information that resource managers need for decision-making,” said Barry, per the release.
