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Today on Animal Fact Files we’re discussing megamouth sharks. These sharks were unknown to science until 1976 when an individual became tangled up in an anchor line of a sea faring vessel. It took almost eight years for this shark to get its scientific name, and it was so different from other known sharks it was placed in its own family. Today, it’s the sole living species of this family, but perhaps more research would shed some new light on where this shark should be classified. As of this recording, only a few dozen megamouth sharks have been captured by humans, and fewer than half have been saved for scientific study, so information is currently limited on these fascinating creatures of the deep.

One look at a megamouth shark explains its common name. These sharks are one of three filter feeding shark species - one of the other is the basking shark, but does anybody know the third? We’ve talked about them previously! Megamouth sharks have gill rakers which are structures that act like a sieve for gathering small planktonic animals from the water as the sharks swim. Now, a lot of people believe that all sharks have to keep moving in order to breathe, but that’s a myth and megamouth sharks are one example of a shark species that can still breathe while standing still!

Megamouth sharks can reach more than sixteen and a half feet (5m) in length and average 1,874 pounds (850kg) as adults, but these sharks eat some of the smallest animals; and, believe it or not, megamouths are actually the smallest of the three filter feeding shark species! The planktonic animals megamouth sharks typically eat are krill, though they have been found with both copepods and jellyfish in their stomachs. There’s thought megamouths might have either luminous or reflective surfaces in their mouths that help to lure in prey, but this hasn’t been confirmed. These sharks follow their prey throughout the day and night and thus make large vertical migrations during a 24-hour cycle.

Throughout the day, megamouth sharks cruise along at approximately 492 feet (150m) below the waves, though they may dive much deeper than this, too. At night, as the sun sets and food moves towards the water’s surface, megamouth sharks follow and spend their time cruising at depths of about 60 feet (18m). Megamouth sharks aren’t really quick swimmers meaning they aren’t the most athletic sharks, so they have big, squishy bodies. While this may be great for snuggling and hugs - something these sharks might actually do - it’s not great for fending off parasitic cookiecutter sharks who can easily catch up to a slow moving megamouth and tear of bits of soft flesh. Megamouth sharks are so soft even their fins are flexible, so this coupled with sharing habitat with cookiecutter sharks makes them an easy target. There have also been reports of megamouth sharks being - what’s been described as - “played with” by sperm whales but how this affects the sharks remains to be seen.

Megamouth sharks are believed to be found around the world in temperate and tropical waters, though larger concentrations have been seen in the Pacific and Indian oceans. It’s thought males begin breeding at a smaller size than females. Males may be sexually mature at around 14.7 feet (4.5m) in length, but females of this size were found to be immature. Female megamouth sharks may not become reproductively mature until they reach sixteen and a half feet (5m) in length or longer. As of this recording a pregnant female megamouth shark has never been observed, so there’s really no information on what pregnancy is like for them. One observation that has been made is that larger female megamouths have scars in the shape of a male megamouth’s mouth - this could indicate that males nibble at their mates while they mate, which, in a way, means they’re cuddly. Currently, most accept that these sharks likely give birth to live young who are fed unfertilized eggs while inside the womb. Sharks that develop in this way usually take a long time, perhaps upwards of a year or longer, to develop, and females may not reproduce again for an amount of time between births, potentially years. Of course, without data, none of this can be said with any certainty, and new research will hopefully shed some more light on these giants of the deep!

For more facts on megamouth sharks, check out the link in the description. Thank you to MarvAlice for today’s request! Give a thumbs up if you learned something new today, and thank you for watching Animal Fact Files!