Tokyo Sea Life Park began exhibiting John Dory in the "Deep Sea IV" tank in the "World's Oceans" area on January 14, 2016.
John Dory inhabits the seabed at depths of 70 to 100 meters. This fish is characterized by its large, elongated dorsal fin membrane, its long, flattened body, and the large, white-bordered black spots on its sides. It is quite sensitive to changes in sound and light, becoming restless with even slight disturbances, and is difficult to keep in captivity as it only readily eats live prey. The highlight of keeping John Dory is undoubtedly the moment it eats. While it usually swims leisurely around the tank, it shows a completely different side when it's time to eat.
John Dory, not being very fast swimmers, slowly approach their prey, small fish, to avoid being noticed. When they get close enough to prey on the fish, you can witness a shocking sight. Their mouths, which normally seem unremarkable, suddenly open wide into a tube-like shape, and in an instant, they swallow the small fish whole, along with the seawater.
In fact, John Dory 's mouth can be folded and extended far forward. Its swift predation and the way its mouth protrudes so large are truly astonishing, and it's hard to imagine from its usual swimming posture.
It was named "John Dory" (horse-headed snapper) because its extended mouth resembles a horse's head. There are also several theories about the origin of the name; one theory is that the black spots on its body resemble an archery target, hence the name "Matodai" (target snapper) which later evolved into "John Dory".
As mentioned earlier, John Dory are reluctant to eat anything other than live prey. However, in order for everyone to witness this amazing feeding behavior, we will continue our efforts to acclimate them to eating fresh horse Japanese Jack Mackerel and anchovies. The sight of so many magnificent John Dory swimming around is truly impressive. When you visit the park, we hope you will take a moment to stop and observe them closely.
[Tokyo Sea Life Park]
(January 30, 2016)
