Not Just Jaws: Shark Facts Fresh from Indian Seas

A shark isn’t just a single scary, predatory fish with a prominent dorsal fin. Sharks come in many sizes and shapes and display a range of different behaviours. Worldwide, there are over 440 species of shark that have been identified, each with its own unique characteristics and habits. And since sharks tend to favour warm tropical and temperate waters, the seas around India have plenty of them. Of the scores of species of shark found in Indian waters, here are facts on five of them. All of these sharks are caught and killed for their fins, meat, liver, and/or skin, and ironically, humans are more of a threat to them than vice versa.

With prominent white tips on the dorsal (top) fin and tail, whitetip reef sharks are relatively small, rarely exceeding five feet. Whitetip reef sharks are not aggressive to humans, unlike their namesake the oceanic whitetip shark, though their down-slanted mouths do give them a rather disgruntled expression. They are somewhat curious, often getting close to divers to look them over. They reside around coral reefs, with blacktip reef and grey reef sharks, feeding on bony fish, octopus, and crustaceans. They rest in communal groups in the day time and are nocturnal hunters heading out in groups, though it’s ‘to each its own’ when it comes to feeding.

Among the largest of sharks, tiger sharks can grow up to five metres and 800 kilos. Their stripes give them the moniker sea tiger, though the stripes tend to disappear as they grow older. With excellent eyesight and sense of smell, these nocturnal creatures easily hunt sea creatures smaller than themselves including turtles and dolphins, and even the occasional bird. They have a reputation for being solitary and for eating anything, which sadly includes inedible man-made garbage.

Also called leopard sharks, zebra sharks wear a coat of stripes when they are young which turn into spots once they become adults. Growing up to five or six feet, they have an elongated tail fin. These graceful creatures are known to be docile and harmless to humans. Slumbering through the day and foraging the reefs for food at night, they like to be alone. Suckerfish (or remora) share a symbiotic relationship with zebra sharks—they attach themselves to the shark’s belly feeding off parasites, dead skin, and leftovers from its meals, and for that privilege they keep the shark clean.

Not to be mistaken with blacktip reef sharks, oceanic blacktip adults are dark brown-bronze to grey in colour on their upper surface and white underneath. They have black tips on their fins and tails (except on the anal fin). With long, pointy snouts and streamlined bodies that are almost five feet in length, these sharks look scary and are often mistakenly thought of as aggressive. Unlike most sharks, oceanic blacktips sometimes make spinning leaps out of the water while hunting.

The tawny nurse shark is large and cylindrical species that grows to ten feet, but is not aggressive and harmless to humans unless provoked. It’s related to but different from the nurse shark found in Atlantic waters. Tawny nurse sharks tend to be slow-moving and stay near the ocean floor. They have the ability to camouflage themselves by changing their colour to brown or grey, depending on their environment. These nocturnal sharks lie in rocky caves and crevasses in small groups during the day and emerge at night to hunt.