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Henry, an Alaskan GPO

May 7, 2004
I'd like to introduce my current GPO, Henry. By way of introduction, I'm the aquarist at a small public aquarium here in Juneau at the Macaulay Hatchery Visitor Center, a private non-profit salmon hatchery. We have 13 small (50 - 90 gallon) and one large 5,000 gallon saltwater aquariums to display local marine life.

Two years ago, I was tidepool collecting and found a baby GPO about 2 inches long. I brought it back and put it in a small observation container inside a 90 gallon tank that primarily has sea stars, plus a few small hermit crabs and shrimp. A few days later the octopus disappeared and I figured that it escaped through the circulation slats in the container and went down the drain line that eventually leads to an overflow that goes out into open water (we are located beside saltwater).

Six months later, I had finished cleaning that tank and was preparing to leave, when I looked back and saw a 6 inch long octopus - my octopus! It had escaped all right,but had found a home in the rocks stacked along the edge of the tank. Apparently it had subsisted on the regular food I'd fed the sea stars (salmon, herring, squid, krill, myscid shrimp, bloodworms, and daphnia). I'd also noticed a few shells from the hermit crabs
on occasion, so as it had grown the crustaceans had provided some live food.

Over the next 8 months, it'd appear at random intervels, but I was never able to find its den when I moved the rocks around. Finally in July I tracked it to a flat rock on the bottom to find that it had burrowed into the gravel under the rock. It promptly vacated that location and hid out under another rock that was leaning up against a side where it was visible from the outside. That was a big thrill for our staff and visitors alike, so the tour guides named it Henrietta as it appeared to be a female, lacking the spermatore transfer arm of the males. I decided to bulk up the octopus and began adding live crabs and shrimp as I collected them. That was last July.

Now it is over 2 feet total length and I think that I should probably slow down the live shrimp and crab feeding as I don't want to get it too big for the tank. I have had a really big GPO donated by the boss's neighbor a few years ago (5 foot TL) in the same size tank and it actually did okay for the 8 months that I had it (it died). Over the years I've had quite a few GPOs that people donate after catching them in their crab or shrimp pots and they generally live 6 - 18 months in our tanks. I've also had a few females that have laid eggs, having mated before capture, and I've had the eggs hatch. No survivors though, since they either were eaten by other animals in the tank or went down the drain.

According to our aquarium permit from the state, the animals are to remain in the aquariums until deceased, so I'll keep the octopus accordingly. If it really does grow big, however, I'll seek a dispensation to release it as I would not want to have to terminate it unnaturally. I've done that one other time when one
octopus really did outgrow its tank (another story of its own).

My middle school daughter is presently making a video for her technology class that shows me doing a little feeding experiment
to see Henry's preference between a crab and shrimp. Hopefully I can post it later on. Note the name change from Henrietta to Henry... it is a male, since the spermatore transfer arm became apparent as it grew this fall.

Henry' personality seems to be developing as he grows. As noted above, he was a very shy individual up until recently and tended to hide out most the time. Now he comes out quite frequently and he actually seems to trying to train me to feed him when he does, since I've been putting in shrimp and crab for him often times when he appears. During the last tank cleaning, he wrestled with me for awhile and then gave me a full face blast of cold water - just like a feisty teen-ager!

I will try to get the video and photos posted as I get some.
May 7, 2004
Henry's jar trick

What got me started in introducing Henry was my response to the octopus jar opening tricks thread a few days ago in the octopus care forum. I'll include it here to expand on Henry's personality.

I've been feeding my GPO (presently about 2 ft. TL) live shrimp and crabs and finally decided to try the old jar trick. I put a coonstripe shrimp in a 7 liter plastic observation container that I'd gotten earlier from Acorn Naturalists that has a snap on lid, which takes a bit of effort to pop open. I'd just fed the octopus another coonstripe about twenty minutes earlier, so I wasn't sure that it would even be interested. The container lid had trapped a bit of air in the container so it floated around in the tank for 5-10 minutes. The octopus eyed it a few times and touched the container rather tentatively without seeming interest. Then all of a sudden, wham, it grabbed the container, straddled it, evidently popped open the lid by sucking on with its suckers, and then checked out the shrimp with one of its arms. After that the action was hidden from view by the octopus's webbing. I had other duties to attend to but when I retrieved the container an hour later, no shrimp and the lid had been wrenched out of its hinges, so the suction must have been pretty strong. The largest suckers on the animal are about 1/2 inch in diameter and it grips very well when I clean the tank and it "wrestles" me.

That was the first time I had put any food in any container, but it didn't require any learning time at all - just wham, bam, thank you ma'am. Pretty amazing.
Mar 23, 2005
Thanks so much for posting this. Henry (Henrietta?) sounds fascinating, and must provide great enjoyment for both staff and visitors. Is there a possibility that your aquarium could acquire a larger tank, something that Henry could grow into?
May 7, 2004
The boss just emailed me a site on acrylic aquariums for "future reference" and I emailed back about Henry's recent growth spurt and probable desire for a bigger tank. We'll see....

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