The International Group for Historic Aircraft Recovery said Friday that based on all available evidence, it was reasonable to assume Earhart and navigator Fred Noonan could have survived for a while on Gardner Island before succumbing to starvation and lack of water.
The conclusion was bolstered by artifacts possible linked to the castaways that were reported found on Gardner in 1940.
Earhart and Noonan vanished during an attempt to fly around the world. They had been en route to Howland Island and were forced to make an emergency landing on a narrow reef when they ran out of fuel.
The Christian Science Monitor said the pair had enough fuel left to power the plane's radio for a few days until surf washed it off the reef.
Leaders of Delaware-based TIGHAR said that U.S. military rescuers were unable to track down the SOS messages and eventually abandoned the search. "When the search failed, all of the reported post-loss radio signals were categorically dismissed as bogus and have been largely ignored ever since," said TIGHAR Executive Director Richard Gillespie.
TIGHAR said the next step in its investigation will be an expedition to the area in July that will include an attempt to find the missing plane at the bottom of the sea using a remote-controlled submersible.