Daily London
The Canadian woman was found unresponsive on the beach north of Maheno Wreck shortly after 6.30am.
Police believe she may have gone for a swim around 5am
They are working to determine how she died, including investigating whether she drowned or was the victim of a dingo attack.
9News understands the teenager had been living on the island, working at a backpackers hostel.
A crime scene has been established.
Police are asking anyone with information or dashcam footage or who may have witnessed something to come forward.
