Juveniles will swim near the shoreline in search of food , sometimes in water as shallow as 12 m ( 39 ft ) .
Adults typically stay at depths greater than 100 m ( 330 ft ) .
Juveniles will swim near the shoreline in search of food , sometimes in water as shallow as 12 m ( 39 ft ) , but adults typically stay at depths greater than 100 m ( 330 ft ) .