Whether it’s Adam Driver in cat form, or a smile amongst the stars, we humans have a knack for finding familiar faces in strange places. And as it turns out, shark researchers are especially good at that party trick. Ladies and gentlemen, we bring you, Mr. Jay Leno (shark edition).
Pack in in, folks, we can all go home now.
It might look like another internet fake, but this image is very real. “Jay Leno” is one of over 250 great whites identified in the Monterey Bay Aquarium‘s fin ID database, which aims to help researchers track the migration patterns of the ocean’s most notorious predators as they mosey along the California coast. It’s thought that these sharks begin their lives, and subsequently return to mate, in the blue waters off Mexico’s Guadalupe Island (temporary stomping grounds of the behemoth “Deep Blue”). A layover near central California’s elephant seal rookeries means the whites have enough nutrients to complete the journey.
Aquarium staff have been identifying individual sharks in the area for over two decades, using the combination of scars, notches, and pockets on their dorsal fins as a guide. Much like your fingerprints, a shark’s dorsal ‘print’ is unique to that animal (essentially, the shark version of that silhouette you overpaid for once-upon-a-yesteryear at Disneyland). While each animal is given an ID number in the database, some fin-flair simply demands an accompanying nickname.
“In order to tell them apart, we like to think of something descriptive to call them: Middle-notch, or Split-fin, or Rooster,” says Senior Research Scientist Dr. Salvador Jorgensen. “We have a shark called Hitchcock. We have one called Elvis.” And of course, there is Jay Leno here. After scrolling through thousands of individual photographs, something like this was bound to show up.
“It’s really exciting to see these old friends year after year,” he says. “We get to know them, and hope to see them again the next season.” Elvis, for example (named for his pompadour-shaped fin) has been seen 27 seasons in a row.
What causes all of those grooves? Good question. A number of factors could be at play in the formation of the fin-print. Fearsome as their reputations may be, sharks play host to countless creatures that feed upon their various body parts. The most easy to spot, are a group of parasitic crustaceans called copepods (you can actually see some dangling off the fin in the photo above). When sharks are young, some copepods attach to the fins, causing sores which, over time, can scar, creating a notch. Inter-species fighting and aggressive biting during mating can also contribute to the fin’s tattered-flag appearance.
Before you start to panic, you should know that a shark’s dorsal fin contains no nerve supply, and even if it did, the sharks studied to date lack the sensory receptors (known as nociceptors) associated with pain as we know it. Any response to injury is more like a reflex than anything else. It’s a good thing too, because copepods don’t always take a back seat when it comes to their shark hosts: over 90% of Arctic Greenland sharks are found with a pinkish-white copepod known as Ommatokoita elongata permanently attached to their eyes, boring in deep to feast on their corneal tissue.