The dusky or lemon shark, is a large shark, almost like a bull shark, and its name comes from the fact that, depending on the light, its back is a light yellowish brown color. It is also known as a dusky shark in many areas of the Caribbean Sea, where some years ago, specifically in Bahamian waters, I was able to investigate certain things about its behavior.
The first thing we had to get them to approach and stay around us. What better than bait boxes hanging under the boat and on the bottom. I got down on my knees next to the latter and waited for the sharks to surround me. I was calm and determined, but seeing myself alone among so many sharks made me take extreme safety measures.
Before making any physical contact with them, I decided to verify that I did not arouse their interest, and that if they were around me it was only for the bait.
The first test I thought of was to take a small piece of bait out of the box, put it close to my chest and move as fast as possible away from them. The sharks did not dive at me as the coral ones would have done, but they followed me slowly, unperturbed but attentive, for a long way, always surrounded by the large remoras that usually escort them. When I considered that I was at a safe distance, seeing that they were still following me, I took advantage of the fact that one was facing me to release the bait when I was close. The shark gobbled it up in one bite, and turned in such a hurry that it brushed me with one of its pectoral fins as it passed. But it totally identified what was bait and what was a "diver"....
I repeated the test once more, aware that I could not do it with either coral or silky sharks, which are much faster and more nervous, and the same thing, every time I took some bait and moved away, some specimens followed me. Not all of them, of course, the bait from the other boxes also kept other specimens attracted.
The real test came when I made the same gestures without taking any piece of fish and I ran away as before. When I turned my head back I saw that none of them had followed me. All of them, absolutely all of them, kept circling around the other boxes. That convinced me that I was of no interest to the lemons, and that once again, they know exactly what's what: bait and divers.
The second test was more complicated, I started to make sudden movements with my right hand from the bottom to the top, and that attracted the interest of the sharks.
I had come down with a chain mail glove like the one Cristina Zenato used, in case the metal had something to do with her way of calming the sharks by caressing their noses. It was not unreasonable to think that the steel somehow altered their electromagnetic receptors, the famous ampoules of Lorenzini, causing them a kind of pleasant short-circuit that left them paralyzed.
The thing is that I noticed that they were paying a lot of attention to my hand, I guess that the metallic reflections of the glove reminded them of a fish, to such an extent that on one occasion I raised it above my head and one that was coming from the front raised his and jumped to bite it. I immediately turned around, stuck it to the side and the shark passed me by, but I can say that I saw its jaws in close-up and I could appreciate the differences between the type of teeth of one and the other. From then on, I moved in a slow and controlled manner, and the incident did not happen again. This proves that one of the tips I always give when diving with sharks is to stay calm and do not make sudden movements with your arms or legs, otherwise, there may be an incident.
After these tests, I kept watching them to try to keep one of them still. The sharks would trace the same course over and over again, approaching the box at ground level and slowly moving away for another lap, so I positioned myself a couple of meters away on one of the starting lines and waited for one to come in very slowly to gently hold it by the dorsal fin and start stroking its nose with my gloved hand. The shark tugged a little when I held it, but as soon as the caresses started, it let go and landed on the bottom. I moved my thumb relentlessly stroking the shark's snout as if winding a huge clock, and the shark seemed so devoted that I decided to switch my left hand from the front to the back of the dorsal fin. I then began to lift it slowly, the shark remained still and calm, but when I had reached a thirty-degree inclination, another shark nipped at the hand with which I was stroking its snout. I guess the gleam of the metal glove moving rhythmically made it think it was easy prey. Surprise caused him to jerk his hand away, my "catch" twitched, gave a tail shake and went away.
It was bad luck, although I think I was also partly to blame, maybe if I had stayed longer and moved more slowly I would not have attracted the attention of the other shark, but my impatience got the better of me.
Even so, I was happy with the trials with the "gallant" sharks, especially to see how they reacted to the bait and the sudden movements of my hands.
I always say that it is not so bad to "bother" them a little bit, as long as you know how to do it and certainly with some research motive, to learn from their behavior and to teach about it...
