There’s something about sharks. I can’t quite place it, but somehow sharks have made it onto man’s list of animals that represent some terrible facet of human nature. The shark’s role is as a cold-blooded killer, an animal that kills without mercy and preys upon the weak. I just don’t get it. Every predator attacks weak and sick prey. And every predator kills its prey without mercy. When you have to spend the majority of your time looking for your next meal, you don’t have the luxury of picking a healthy fit animal or letting a creature go just because it’s little and cute.
So why do we blame sharks for being ruthless when things like tigers and wolves are just as bad? I assume it’s because tigers and wolves are cute, or beautiful, whereas it’s much harder for us to relate to sharks. Not to mention sharks seem to have dead, unfeeling eyes, which doesn’t add to their cuddle factor. Still, I think these creatures get the short end of the stick in human culture. I’m not here to set that right, but I will write about one of the largest predatory sharks, the tiger shark.
Tiger sharks live in tropical and subtropical areas, and have a large range along coastlines in these waters. They like warm waters, and tend to move with warm currents. They can be found at varying depths, from super shallow coastal waters to depths up to 900m.
Tiger sharks are big, and can grow over 5 meters in length in exceptional cases. Female tiger sharks are bigger than males, and one specimen was apparently 5.5 meters long. They are called tiger sharks because of the striped pattern that is present on juvenile sharks, though this disappears with age and adults are usually blue or blue-green with a white belly. This type of coloration is common in sea creatures (I’m sure I’ve mentioned it in other posts), and helps camouflage the animal. Basically, if you’re above a tiger shark in the water, you’ll see its dark side, and it will blend into the dark ocean below it. If you’re below the shark, its white belly will camouflage it with the sunshine-lit waters. Of course, tiger sharks are big and don’t really have to worry about predators, but this camouflage helps sharks sneak up on unsuspecting prey.
In order to stalk prey, you first have to find it. Tiger sharks have a number of adaptations that help them do this. They have special organs on their nose called ampullae of Lorenzini, which specialize in detecting electrical fields. Another organ, the lateral line, senses tiny vibrations in the water. Using these two organs and their eyes, which have a reflective layer to maximize the amount of light that enters, tiger sharks can hunt and catch prey in murky, dark waters.
Tiger sharks will eat pretty much anything. They are known to have one of the widest ranges of prey of any shark species. They eat fish, squid, crustaceans, birds, sea snakes, dolphins, dugongs, sea turtles, and a long list of other things. They are so indiscriminate that they often will eat man-made objects like licence plates, tires and baseballs. Basically they are giant garburators.
Sharks can be scary – they are big and have huge teeth. Tiger sharks do attack people, though this is rare. Be smart and stay out of tiger shark waters and you’ll be fine. Still, I think we have to appreciate wonderful large predators like the tiger sharks. They keep us humble (or they should).
Cover image By Albert kok – Own work, CC BY-SA 3.0