i've been sailing on mobile for awhile and have been all around the island but only recently found one chilling right next to my base, next to the red obelisk. it spawned kind of deep, but i managed to shoot it from the beach. it was just a lvl 1 with 4400 health and i was able to take it out in a few shots with my rifle, but it didn't attack at all. they seem pretty chill in mobile.