Spectacularly Rare Megamouth Shark Filmed On A Coral Reef

by | Jul 25, 2017 | Fish | 0 comments



The Megamouth Shark (Megachasma pelagios) is one of the ocean’s most enigmatic giants. It can grow to 17 feet in length and can weigh upwards of 2,600 pounds, yet, despite its colossal proportions, it was entirely unknown until the first specimen was discovered wrapped around a ship’s anchor in 1976. Since then, only around 100 specimens have been encountered. Images of this reclusive fish in life are exceptionally rare, but a remarkable new video has just surfaced of a specimen that was observed in the shallow waters of Komodo, Indonesia.

Megamouths are one of just three species of filter-feeding shark, along with the Whale Shark (Rhincodon typus) and Basking Shark (Cetorhinus maximus). Both of those can reach over 40 feet in length, making Megachasma the relative pipsqueak of this group. It occurs in tropical waters around the world, but the majority of documented specimens have been encountered in the West Pacific, particularly from Taiwan, where this shark is a semi-regular bycatch in the local gillnet fishery. The known depth range extends from surface waters down to 1500 meters, with shallower records tending to be either sick individuals or observations taken at night.


The diet of the Megamouth is comprised primarily of krill, and it is thought to follow the vertical diel migrations of its planktonic prey. This likely explains why observations are so scant, but it also raises the question of what this filmed specimen was doing around a shallow coral reef. Megachasma typically swims about with its mouth agape in search of prey, but this fellow has a noticeably clenched jaw. Was it commuting? Was it lost? Was it vacationing?

  • Joe Rowlett

    Joe is classically trained in the zoological arts and sciences, with a particular focus on the esoterica of invertebrate taxonomy and evolution. He’s written for several aquarium publications and for many years lorded over the marinelife at Chicago’s venerable Old Town Aquarium. He currently studies prairie insect ecology at the Field Museum of Natural History and fish phylogenetics at the University of Chicago.


Submit a Comment

Your email address will not be published. Required fields are marked *

Upcoming Events