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Today on Animal Fact Files we’re discussing basking sharks. We’ve previously talked about the largest filter feeding shark, the whale shark, as well as the smallest filter feeding shark, the megamouth shark, so it’s about time we discuss the middle sized filter feeding shark, the basking shark. When put in a list like this there might be some impression that basking sharks are “small” sharks, but make no mistake, all the filter feeding sharks are chonkers. The basking shark can reach lengths of 33 feet (10m), though there are reports they may get even longer. These sharks swim with gaping mouths so they can collect their food which consists of tiny animals like copepods, crustacean larvae, and fish eggs. Take a look inside a basking shark’s mouth and you’ll see slits through which water passes. These are the shark’s gill slits and it’s here they’ll collect their food. A basking shark’s food gathers on structures called gill rakers which are kind of like combs. As the water passes through, the food gets caught on these comb-like structures. Every once in a while the shark will close its mouth and swallow whatever has been collected. In a single day, a basking shark may filter over 2,000 tons of water per hour!

Basking sharks live in temperate oceans throughout the world. They’re highly migratory. For example: in the Atlantic along the North American coast basking sharks may be seen from North Carolina to New York during the spring, from New England states to Canada in the summer, and then disappear completely until the end of winter! These sharks may live in the open ocean or coastal waters even venturing into coastal bays! Their name, basking shark, likely comes from their behavior of basking on the surface of the ocean, but they’ve also been sighted in deep water basins reaching two and a half miles (4,000m) in depth. It’s believed that during the winter months basking sharks spend most of their time towards the bottom of the ocean. These sharks periodically shed their gill rakers beginning around early winter. Without gill rakers, they may not be able to eat, so they may enter a hibernation state while their gill rakers regrow over the course of four to five months. Of course, they may also just take up a different food source. Instead of filter feeding they may seek out bottom dwelling prey. Or they might subsist off their large livers until their gill rakers grow back in. Honestly, nobody knows for sure.

The greatest threats to basking sharks are humans who catch them in fishing and may collide with them in boats. There’s also suggestion that orcas may kill basking sharks as there has been a pod of orcas seen near a dead basking shark, though this is mostly anecdotal. Deceased basking sharks are eaten by opportunistic great whites, as well. Basking sharks are distinct from whale sharks because they’re lacking in the checkerboard patterning found in whale sharks; basking sharks can also be told apart from megamouth sharks because they have pronounced, pointed noses where megamouths have flat faces. Basking sharks may travel alone, in pairs or small groups, over even in huge groups numbering up to 100 members! These crowds can be seen soaking up the sun at the surface of the water, though they are generally lacking in pregnant females. Very little is known about basking shark mating habits. They likely perform some sort of biting during courtship because individuals have been found with scars that correlate to the mouths of other basking sharks. It’s also believed that the young eat eggs produced by the females while in the womb and are eventually born live. Gestation in basking sharks may take from one to three years and they may wait years between litters; maturity may be reached anywhere from 6 to 20 years of age, and there’s an estimate that basking sharks can reach 50 years of age, but none of this is certain. More research is needed! Though they’re huge, basking sharks are able to jump completely out of the water and it’s believed they do this to remove parasites!

For more facts on basking sharks, check out the link in the description. Give a thumbs up if you learned something new today, and thank you for watching Animal Fact Files!