Urban Dweller: The Giant Pacific Octopus

Giant Pacific Octopus in riprap den
Giant Pacific Octopus (GPO) in artificial boulder habitat  in Elliott Bay, Seattle

Coastal cities are not just home to high densities of humans. Octopus may also come to dwell in urban landscapes in large numbers.

This is what we’re finding in an underwater study we initiated earlier this year. We conducted video surveys at a series of paired, neighboring dive sites where artificial structures were abundant vs. sparse. The addition of artificial structures to the marine environment is a major part of urbanization in coastal cities. Artificial structures can consist of anything from sunken cars to old toilets to discarded garden gnomes.

Giant Pacific Octopus in some junk
GPO in south Seattle, in a den made out of an old iron hatch

Without revealing the full punch line (we’ve yet to submit our findings for publication), I can say that octopus densities tend to be higher at sites where there’s more junk. This may come as no surprise to long-time divers in the Puget Sound region. Scientists also have been aware of the use of artificial structures by octopus for some time. What’s so striking is the extent to which artificial structures appear to increase octopus abundance in even the most heavily urbanized locations.

Here’s a great video from UW research diver, Ed Gullekson, of octopus and several other critters that live just off of downtown Seattle, in Elliott Bay:

For more great videos from Ed “Sharkman” Gullekson, check out his Vimeo page here!