Shark Facts

Sharks, skates, and rays are collectively termed Elasmobranchs, a subclass of Chondrichthyes, or the cartilaginous fishes. They have a skeleton made entirely of cartilage rather than bone as in other fishes.

In general this group is slow growing, late maturing, and produce few young compared to other fishes. These characteristics make them especially vulnerable to exploitation by humans.  For more information, see our page on Threats To Sharks.

Sharks have a streamlined body, 5 to 7 pairs of gill slits depending on the species, and skin covered in small scales called dermal denticles which make the skin feel rough and sandpaper-like. They do not have a swim bladder for buoyancy like other fish but have a large oil-filled liver.

They also possess a lateral line, a sensory organ comprised of a narrow line of sensory cells that runs the length of the body and into the head. Some pelagic (open ocean) species do not have spiracles and rely on actively swimming to move water over their gills in order to obtain oxygen from the surrounding water. 

Skates and rays have pectoral fins that are enlarged to form “wings” that propel them through the water and have flattened bodies which help them to feed on the bottom. They are mainly bottom-dwelling with the exception of eagle and Manta rays. Worldwide there are more than 1,100 species of sharks, skates, and rays.

Whale Shark

Whale sharks are the largest fish on the planet. These gentle giants are filter-feeders and are harmless to humans. The enormous whale shark, which can reach lengths of 40 feet or more, feeds on the tiniest of ocean organisms, plankton. 

Whale sharks are striking in their appearance not only for their size but also for their unique pattern of spots and bars covering its gray body. The whale shark is popular with ecotourists hoping to snorkel alongside these gentle giants. Learn more about whale sharks.

Manta Ray

The manta ray is striking in its appearance with its black and white coloration and enormous size. The wingspan of a manta can reach 20 or more feet across and they weigh as much as 3,000 pounds. The manta, unlike other rays, does not have a spine on its tail for defense. 

The manta is a filter-feeder, combing the waters for the smallest of prey, using their cephalic fins to channel water into their mouths. Mantas are found globally in temperate and tropical waters. Learn more about manta rays.

Hammerhead Shark

There are nine species of hammerhead sharks worldwide. The hammerhead with its strangely shaped head is somewhat of a mystery although scientists have recently discovered that the odd shape improves their vision, making them excellent hunters.

The Great Hammerhead, the largest of the hammerheads, can reach a length of 25 feet, almost the size of a Great White shark. Hammerheads are known for their schooling behavior, congregating in large groups in places such as Cocos Island off the coast of Costa Rica.

The hammerhead consumes a variety of prey including rays, other sharks, fish, squid, and crustaceans. Learn more about hammerhead sharks.

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We're a non-profit wildlife conservation travel organization that supports local efforts to protect endangered animals. We work with quality tour operators who have passed our criteria to ensure low environmental impact. We're part of The Ocean Foundation.