Puget Sound Octopus Survey 2001

By Roland C. Anderson
The second annual giant Pacific octopus survey was conducted in Puget Sound on Feb. 17, 2001. This survey is designed to give us an idea of how many octopuses there are in Puget Sound, see if the population is healthy, and determine if there are seasonal fluctuations in the octopus population. Dr. Roland Anderson, Puget Sound biologist at the Seattle Aquarium, organized the survey. Roland instructed all divers participating in the survey to record the number of animals sighted and to report them to the Aquarium. Last year 114 divers saw 18 octopuses, most of which were in Hood Canal. This year 67 divers reported 15 octopuses, all of which were seen in Puget Sound proper. None were spotted in Hood Canal on that day this year.

Fewer divers participated in the survey this year than last, possibly because the count was held the day after the season's worst snowfall. Although the snow was melting, many areas had black ice on the roads in the morning and this may have kept some divers out of the water. In spite of fewer divers, more octopuses were seen per diver this year. Octopuses were seen at Day Island, Sunrise Beach, Maury Island, Tramp Harbor, KVI Towers, Seacrest, Edmonds, and Port Orchard Rock.

It is strange that no octopuses were seen at the underwater preserves of Sund Rock and Octopus Hole on Hood Canal. Last year the same divers looking found 10 octopuses at these sites.

Octopuses are highly mobile. Although it is possible octopuses have been poached, it has been proven that octopuses only spend about one month in any one den, and then move on. It may be that they had eaten all the crabs at the Hood Canal sites and then moved. Divers at Hood Canal this year saw wolf eels and ling cod guarding eggs in dens that formerly held octopuses. It is possible that after the ling cod eggs hatch, the octopuses might return.

Four octopus sightings last year were females guarding eggs, but none were seen this year. Females usually block up their dens with rocks and are hard to spot, so they may have been missed.

Surprisingly, no octopuses were seen on a dive in the Tacoma Narrows on that day, and we received no reports from the Keystone Jetty, which is usually a good place to see octopuses. Although we only have two years' worth of data so far, it looks like there are fluctuations in the population from year to year, certainly by location. We'll know more as we get the information from surveys in future years.

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  • Published
    Feb 22, 2015
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