Jim Duran and I started a night dive in about sixty to seventy feet of water several miles off the beaches of Panama City, FL. I was wearing double 80 tanks, held a collecting bag and lights, and fully intended to capture an octopus, alive.
At the time I was working in an invertebrate physiology laboratory at Florida State University, under the mentorship of Dr. Michael Greenberg. I had been impressed by the reputed high intelligence of the octopus and was also interested in the effects of high pressure. The Navy base at Panama City had a new high pressure chamber, capable of simulating deep-sea pressures. Since I was in training in the combined Navy and NOAA program called the Scientist in the Sea, it seemed logical to me to catch an octopus and study it to see if it would be a suitable candidate for testing in the Navy’s giant hyperbaric chamber.
It sounded like a reasonable plan to me, and Jim Duran was willing to follow along as my assistant critter catcher. And to begin with, the plan worked. We spied our quarry only a few minutes into the dive. The gray-brown octopus was crawling over the sandy bottom and initially seemed unaware of our intentions. But as the two of us closed in on him, specimen bag flapping in our self-generated current, he sprang off the bottom and squirted away.
But we were strong swimmers, and our quarry was in the open, maybe eight feet off the bottom. He had nowhere to hide – silly thing. Keeping our lights on him, and stroking like mad, I began gaining on him, at which time he let loose with his ink. I was prepared for that, and continuing to kick I soon caught up with him and got my hands on him, trying to stuff him into my bag. But he would have none of that.
Off we went again. What we didn’t realize was that the clever invertebrate was constantly turning to our right. We of course were too intent on capturing him to notice his strategy. And besides, invertebrates were incapable of strategic planning – or so we thought.
Apparently, the octopus was determined not to be touched again, or else we were tiring, for we never quite caught up with him. So close, and yet so far away.
And then a curious thing happened. He collapsed his tentacles upon themselves, streamlining his body shape, and shot like a rocket from our depth to the sandy bottom. Once on firm ground again, he spread his tentacles as wide as he could, and his entire body turned white. I froze in shock.
In another instant, before I could recover my senses, he collapsed his body down to the width of an apple and slithered into his hole in the sea floor.
He was gone.
It didn’t take long for us to realize that the chase had started near his home, and he had led us at a furious pace in a large circle, which ended precisely where it had begun. He had maneuvered us to within striking distance of safety.
Humbled, and now growing low on air, and embarrassingly empty-handed, we headed back to the off-shore platform where our dive had begun.
It had seemed like such a good idea. Who knew that two graduate students would be outsmarted by an invertebrate.
Below is a link to a video showing an octopus’ ability to disguise itself, and some of the defensive behavior we witnessed.