Octopus Census Found How Many of These Ocean Giants?

The population of giant Pacific octopus in the Puget Sound has long been ill-studied by scientists, so the Seattle Aquarium decided to conduct a unique octopus census to better assess the health of these ocean giants.

Giant Pacific octopuses - the largest of their kind - live throughout the temperature waters of the Pacific Ocean, including off the coast of Seattle. And despite weighing as much as 150 pounds with tentacles that can span up to 20 feet, they remain among some of the ocean's most elusive creatures.

That's because these octopuses are not on federal endangered or threatened species lists, meaning there aren't current studies on the population in the Puget Sound area. Not to mention that these giants lead relatively short lives, between three and five years, and are terminal maters - once they mate, they die soon after.

But the health of this population isn't a secret anymore, after 27 volunteer divers surveyed 11 sites around Puget Sound, from waters off Seattle to the maritime border with Canada. In all they counted 28 giant Pacific octopuses, compared to just 17 last year.

"We've been watching the numbers go up, then kind of go down, then kind of go back up," Kathryn Kegel, a Seattle Aquarium biologist, told The Associated Press (AP). "That could be having to do with population and mating. As they all peak and mate, they slowly die off, then they start to grow back up again."

While this unique census is indeed informative, it is also informal and not strictly scientific. It's possible the volunteers missed some eight-legged creatures in the area. Like other octopuses, the giant Pacific octopus uses special pigment cells in their skin to change colors and textures, allowing them to blend in with almost any environment, according to National Geographic. Also, they are nocturnal animals that hunt at night - feeding on crabs, clams and scallops - and hide in their dens during the day.

The divers used flashlights and dove in areas historically known for being octopus homes.

But only through yearly censuses such as this one can scientists better understand these ocean giants lurking beneath the ocean.

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