Why Thousands of Brooding Pearl Octopuses Migrate to Thermal Spring Waters to Create The Octopus Garden

Scientists from MBARI have discovered why female pearl octopuses migrate to Davidson Seamount, a nearly extinct underwater volcano to bathe in its warm thermal spring waters while pregnant (brooding). The number of these octopuses is so big, it’s known as The Octopus Garden.

Deep below the ocean’s surface just off the Central California coast, thousands of octopus gather near an extinct underwater volcano. The Octopus Garden is the largest known aggregation of octopus anywhere in the world. …The size of the Octopus Garden—likely more than 20,000 total octopus nests—and the abundance of other marine life that thrives there underscores the need to understand and protect hotspots of life on the deep seafloor

It turns out that the warm waters help the egg grow faster than in cold water.

 Octopus brood periods respond strongly to ocean temperature. The colder the water, the slower the eggs will develop. In the frigid waters found at these depths… we expected it would take five to eight years or even longer for octopus eggs to hatch. But we were amazed to learn that the eggs at The Octopus Garden hatched in less than two years. …

It also increases the hatchling’s ability to survive while its mother is still alive.

In addition to developing successfully, embryos must avoid predation, infection, injury, and more. Maternal care helps protect them from these threats. But sadly, sometimes a mom runs out of energy and dies before her eggs hatch. A shorter brood period reduces the risk that developing embryos will be injured or eaten ensuring that more will survive.

The E/V Nautilus captured amazing footage of The Octopus Garden.