In the magnification of the lenses, the protruding white shell is pearlescent and clam-shaped, with a dark muscular stalk that I gently clamp into the tips of the plastic forceps while I gently rest my right hand on top of the turtle’s huge head. It is as cool and smooth as petrified bone, and I feel him slowly, heavily stir. I’m constantly aware of where his jaws are in relation to me, and I hear the blasts of his respiration and feel the softness of his pink-tinted neck against my leg as he puffs up and emits a loud groan followed by a low growl.

“Now, don’t be such a grumpy old man,” I say to him. “No one’s hurting you, and you’re going to be fine.”

I’m careful not to break or damage the barnacle as I work it out of the leathery skin, and then it is free and I move out of the way so Pamela Quick can attend to the wound, which isn’t what I’d expect if the turtle was struck by something covered with barnacles and stabbed or punctured by a glasslike shell. She swabs the shallow wound with Betadine, and I place the barnacle in my gloved palm. I can see a trace amount of a substance on it, what looks like a hint of bright yellowish green paint on the plate farthest from the stalk, just a faint swipe on an edge of shell that is broken.

I imagine an object covered with barnacles coming into contact with the leatherback, the force of the impact sufficient to drive the tip of the shell into the hard leathery ridge and unseat or pry the barnacle from whatever it was cemented to. But the transfer of paint or what might be paint doesn’t fit with such a scenario, and I envision the natural-gas tanker that passed us less than an hour ago. A number of them I’ve seen are painted garish colors, chartreuse and teal green, neon blue or orange.

“Something painted yellowish green,” I ponder out loud, as I place the barnacle into a small plastic evidence container. “Not likely a rock or a piling. More likely he struck a boat, a Jet Ski, or something like that struck him.”

“A rather insignificant glancing blow, if that’s the case,” she puzzles. “Certainly not the usual thing we see in a boat strike. When these animals surface for air and get hit by a speeding boat or a tanker, usually the damage is profound. He must have been barely bumped by something, or he barely bumped into something.”

“With bright green paint?”

“I got no idea,” she says.

I label the evidence container and feel the boat heave from side to side, the surf getting heavier. The temperature is dropping, and I’m chilled by cold saltwater flowing around my feet, my pants soaked up to my knees underneath white Tyvek.

“Well, if whatever he ran into or ran into him is a boat, for example, that’s a little curious,” I continue, “since most are protected with an antifouling paint, some type of coating to prevent barnacles or other organisms from attaching to the hull.”