Ironjaw sharks are small carnivorous aquatic animals known for their strong jaws, which also granted them their name. It's unknown if the sharks are found outside Vutara Bay or not, but in the Bay they're the largest predator underwater, hunting anything that's smaller than themselves.
The Sirens keep the Ironjaws as pets. These sharks are not generally loyal pets, but they remember who feeds them and will return to this person if the person feeds them a couple of times over a short time. Contrary to general assumption the Ironjaws are surprisingly fond of being stroked on top of their head and along their fins, though they won't generally allow strangers to touch them until they know the strangers aren't a threat.
Ironjaw sharks eat mostly fish and small squids, as that's what lives in the Vutara Bay. They might also catch the odd seagull floating on top of the waters. Whenever a whale or something that's larger than an Ironjaw is roaming into the Bay, the sharks might come together in a hunting pack and help eachother taking the prey down.
Contrary to what people living around the Bay thinks, the Ironjaws don't generally eat humanoids. The sharks don't seem to like the taste of humanoid flesh, as most attacks end up with the shark taking a bite, then promptly spitting it out again before swimming away to find something else to eat. This doesn't mean they're not dangerous, however, as the attacked humanoid might get lethal wounds from the encounter.
(Up to 40 years or more)