Everyday, some strange shit happens out on a reef. We humans, because of our mortal constraints, can't spend nearly as much time documenting and observing fish behavior as we might like. We can't be all "Gorillas In The Mist" because a) we breathe air and make noise and look pretty silly, and b) wee can't follow fish below certain hard floors of depth.
So divers often observe behavior no one much mentions. Some of it is really pretty intelligent behavior. Some of it is just plain weird.
Yesterday, I made three dives, including one at night. Let me talk about that one first, since it's the easiest to discuss. Nothing unusual happened.
There was a near-full moon high in the sky as I descended around 7 PM. Consequently, I decided to make the dive using as little light as possible. The moon would be my guide for most of this night.
It might sound scary and I confess at times it's a bit unnerving, but it is an experience every diver should try, in an environment where they feel safe and secure in the daytime. They ought to know the reef like the back of their hand. To do otherwise is to take unneeded risks.
Of course, I'm all about that, so I decided that in addition to diving dark, I'd dive solo. That's probably not the smartest decision I'll ever make, but on this reef, someone is always cruising by. SomeoneS, I should say. Still, trouble happens and in the dark without lights, no one can see you scream.
(Nothing happened to me that wouldn't have happened if I took a buddy)
The moon casts a bright light into the shadowy areas, so I felt very safe, very able and aware of my surroundings until I hit about forty feet. The sand patches became fewer. I was truly in the dark. The human mind plays tricks. You start to imagine things. I had to shake off the feeling that I was being stalked, several times.
Until...well, in truth I was stalked. By the local tarpon, whom I like to call Charlie, Dave, and Ed. Tarpon are big, human-sized, with ferocious pouts and are apex predators on this side of Bonaire. The occasional dolphin swims into the inlet, the occasion pod of dolphins, even, and once in a rare while, a shark fin is sighted, but apart from those moments, it's tarpon.
Tarpon seem to be pretty stupid fish, but they are curious and this belies that stupidity. They've worked out that "diver + light = dinner."
Here's what they've observed: a couple of divers drop into the dark and immediately turn on their flashlights, looking at all the pretty fish that are swimming around or sleeping.
All those tasty morsels now blinded by the divers' lights or highlighted like museum pieces, just swaying back and forth in the surge. The tarpon hang back just over and behind the divers until they see something they like, and zoom (literally!) in for the kill.
It's an awesome sight. The tarpon will tilt 45 degrees to the vertical and open its rather impressive maw and try to scoop up the fish. I know this because I almost killed a longsnout butterfly fish while scanning a reef looking for an octopus. The tarpon missed, possibly because I shut my light out when I realized what was going on. The tarpon missed, of course, but then swam right straight up to my mask as if to intimidate me into feeding him next time.
He was intimidating. I was no more than two or three feet from one of the most impressive fish in the ocean. It was hard not to be.
I know I was that close because I had to push him away with my hand.
Last night, it looked like Charlie and Dave were lingering about. I only saw Charlie at first (he's the smallest and has the blandest eyes of the three). He made his presence known by swimming underneath me just as I was experiencing that creepy feeling I mentioned.
Let's just say that I made a small contribution towards global ocean warming at that moment. I looked at him, smiled, and swam to a coral head where I knew a lionfish would be "mooning" itself. I had an idea.
Unfortunately, the crevice between coral heads was too narrow and Charlie hasn't worked out that lionfish can be prey. He didn't rise to the bait, so to speak.
I swam in towards shore a little, trying to see if anybody else was in the water. I came across two of my dive buddies and decided at that point to tag along. Pete and Cathy are both very experienced and accomplished divers. Cathy had her camera rig, complete with modeling light, and so you know Charlie and Dave were salivating.
Errrr, if that was necessary underwater...nothing untoward happened, however. Charlie and Dave got bored on occasion and went off to harass a bunch of other divers who were lit up like a Vegas whorehouse, but they came back to check from time to time, sometimes swimming so close I could feel a tail fin smack me on the tank.
Now for the weirdness.
In two dives during the day, I observed three things that made me wonder if I'd moved to a new planet suddenly.
One I had seen before, twice. In fact once on this trip.
Sergeant majors are common reef fish, identifiable by the yellow markings with five dark bars on their sides. You see them on nearly every reef in the Caribbean. Sometimes, they'll appear bluish or even dark blue.
These are males that are guarding their egg masses, a purplish smear across some surface like rock or metal. They'll swim over them, fanning them to keep fresh water on them, and to post sentry to prevent other fish from eating the eggs. It takes about a week from laying to hatching.
Some are pretty passive in their defense strategies. Some are testosterone-fueled professional wrestlers in roid-rage. I stumbled across the latter yesterday. The little bastard bit my leg. Even now, sixteen hours later, it hurts a little, like a scratch. Not content with that, he started gnawing on my fin like a pit bull on a chew toy.
Think about that for a second: this tiny little fellow, maybe three inches long, was willing to take on a creature 25 times it's length, all because I wandered too close to his nest!
I had to laugh a little.
Other weird stuff happened too. For example, I saw a tarpon exhale.
No. Really. We're all taught that fish extract oxygen from the surrounding water using their gills, which also exchange out the carbon dioxide they're excreting. That means no bubbles since the idea is not to have gas because of the differences in pressure as the fish swims, yadayadayada.
Some fish, however, have a form of primitive lung, a swim bladder, which they can use to regulate their buoyancy. I saw a tarpon...burp! As I watched him swim into more shallow water, a stream of bubbles flowed out of his gill slits.
It was quite disconcerting, seeing a fish essentially exhale.
The weirdest thing, the thing that made me start to think, was tool-using behavior I observed in a yellow-head wrasse (I have pictures). This little wrasse, about an inch and a half long, had found a little snack to eat. The problem is, it was covered in a candy coated shell to think for the wrasse to bite thru.
So it did the next best thing to what I can only presume was either a crab or a baby sea urchin. It picked it up, found the nearest rock and began bashing it against the rock.
Now, we've all heard that tool-using behavior is a sign of higher intelligence: dolphins do it, parrots and crows do it, chimps do it. Fish brains are not supposed to be that developed, certainly nothing beyond identifying prey and predator should stay in that tiny little mass of ganglia.
And yet, I saw this fish bash this thing against a rock, drop it, pick it up and go find another, better rock to bash it against! That's not survival behavior, that's tool use! That's intelligence!
We ought to start taking God's mission to watch over the animals of this planet more seriously, because I think they know who to blame here.