Life and death drama is tangible and relentless under the surface of the sea — and sometimes right there on the surface, like when bonito and barracuda slash and swallow baitfish skittering frantically across topwater. On the seafloor, brains as well as brawn rule the day in sometimes fascinating ways.
Here’s an example. We’ve all heard stories about how smart octopus are. Yes, they certainly are capable of figuring out how to open a jar to get to a goody such as a crab (their favorite) or small fish. It only takes them a couple of times of trying the jar lid one way and then the other to figure out “lefty loosey.”
There is more. Commercial lobster fishers like to leave a female lobster in their pots along with the usual bait, to attract males quicker than just a pile of bait will do all by itself. Thing is, surprisingly large octopus can slither and ooze their way inside the pot, eat the lobster and then make their way back out of the pot. Now that’s a nifty trick!
I spoke to an aquarium worker who told me the story of a baffling mystery. They kept bat rays in a tank in a room with no other tanks. One morning they came in to find a dead bat ray with a hole chewed right through its middle. Well, that was puzzling! Other bat rays couldn’t manage to do that.
The very next morning there was another dead bat ray, and yet another the next morning. Finally they set up cameras aimed at the tank and ran them overnight. When they viewed the video they saw an octopus climb into the tank and attack a bat ray. The only octopus in that building was in another room down the hall. That sly critter had climbed out of its tank to go explore in the dark of the night, slithered down the hall, found the bat ray tank and then continued to make nightly treks, being sure to get back into its own tank in time for breakfast to be served.
The aquarium keepers found a way to protect things from foraging octopus. Experimentation showed that octopus can’t stand astro turf. It is probably too scratchy and uncomfortable for them to traverse. So the workers surround things with astro turf. Our commercial lobster fishers and crab fishers might want to try attaching pads of astro turf to the outside of their traps. Lobster and crabs have hard enough exteriors that they shouldn’t mind the scratchy feel and may even find they get excellent traction of the rough surface.
Another learned habit of marine mammal carnivores, such as sea otters and sea lions, is to look for trap buoys on the surface, swim down the attached line and pick off crabs and lobster before the bugs make it into the pots. So marine mammals see our commercial pots as food aggregators.
Astro turf may not help with this problem, but perhaps there is another simple solution yet to be discovered. Any ideas?
— Capt. David Bacon operates WaveWalker Charters and is president of SOFTIN Inc., a nonprofit organization providing seafaring opportunities for those in need. Visit softininc.blogspot.com to learn more about the organization and how you can help. Click here to read previous columns. The opinions expressed are his own.
