Great white sharks are known to invade newspapers, magazines and TV sets, usually painted as savage monsters. However, great white sharks are now making news for an entirely different reason: their migration patterns. Enter Katharine, a shark arguably as famous as the star of Jaws or Bruce from Finding Nemo.
Named after Katharine Lee Bates, who wrote the song “America the Beautiful,” this shark’s trip through the Gulf of Mexico has been heavily monitored by the online masses. In fact, people have become enamored with all 4.3 m (14.2 ft) and 1,043 kg (2,300 lbs) of this immature great white shark. Tagged by OCEARCH in Cape Cod, Massachusetts, on Aug. 19, 2013, seems this girl wanted to catch some Florida sun this summer.
Or, is that all?
Taking advantage of this social media sensation, Sarasota Fins, a local Sarasota shark conservation program, and Tracking Sharks have decided to team up together and dive deeper into the world of Carcharodon carcharias.
Various sharks live in the Gulf of Mexico, and many follow Katharine’s path: straight to Sarasota, FL. These include: the spinner shark (Carcharhinus brevipinna), silky shark (Carcharhinus falciformis), bull shark (Carcharhinus leucas), blacktip shark (Carcharhinus limbatus), tiger shark (Galeocerdo cuvier), and lemon shark (Negaprion brevirostris). Some lesser known sharks include the cookie cutter shark (Isistius brasiliensis), fringefin lanternshark (Etmopterus schultzi), sharpnose sevengill shark (Heptranchias perlo) and the bubble-gum pink goblin shark (Mitsukurina owstoni). And, yes, great white sharks inhabit the Gulf of Mexico as well…. we just know very little on how great white sharks utilize the environment.
What exactly is attractive to a shark about the Gulf of Mexico and Sarasota Bay? Perhaps they’re going to visit Mote Laboratory where Shark Lady Dr. Eugenie Clark resides. Or, since these animals are predators of large schooling fish, she is probably following some food. George Burgess, director of shark research at the Florida Museum of Natural History, has said, “My guess, and it’s just a guess, is that this particular white shark and probably some of its friends are in the Gulf of Mexico looking for tuna fishes. We know that the off-shore area of the Gulf of Mexico is the most important spawning site for blue fin tuna.”
Other animals seen in the Gulf are porpoises, dolphins, small whales and sea turtles. Documentaries showing sharks breaching out of the water to capture unsuspecting seals has skewed our thinking when it comes to great white diets. Seals aren’t the only thing they eat! These sharks can eat different prey based on their age, size, and location. Great white sharks 3 meters in length or smaller have a diet comprised of predominantly fish. After this youth stage, they exhibit a dietary shift to larger prey, like mammals. However, many retain their multi-prey tastes as they age. Due to her circling behavior, she is mostly likely feeding on game fish (and possibly smaller sharks). Maybe there’s even a rare- but yummy- whale carcass.
Not much is known about great white behavior and social structure. However, in South Africa dominance hierarchy is dictated by size and sex; females are dominant over males, larger sharks are above smaller sharks and residents reign over newcomers. Individuals have been seen with bite marks, which may suggest that when sharks get too close, they give out a warning bite to display dominance. So how does this celebrity’s presence affect other local sharks? While it’s known for smaller sharks to make way for larger sharks (so they don’t become a snack), and it can be hypothesized this is what happens when Katharine is cruising by, nothing can be said with 100% certainty.
Melissa C. Márquez