KEY LARGO, Florida - A team of U.S. Navy audiologists conducted a hearing test Saturday on a rare beaked whale convalescing at a marine mammal rehabilitation centre in the Florida Keys.

The mature female whale has been tentatively identified as a Gervais' beaked whale or a Sowerby's beaked whale, said Dorian Houser, a consulting biologist with the Navy Marine Mammal Program in San Diego.

The whale was discovered Friday in shallow waters behind a home in Islamorada. It was transported to the Marine Mammal Conservancy in Key Largo.

Houser and Navy staff scientist James Finneran made a trip to the conservancy Saturday to establish a hearing baseline measure for the whale.

It's something that has only been done once for a Gervais' and never for a Sowerby's. That gives them data they can use for comparison purposes in the future.

"These animals are very rare," Houser said. "Usually, when you find one stranded, it's dead."

Researchers were taking blood samples from the 4.3-metre-long,724 kilogram whale to try to determine why it stranded.

It also was being rehydrated with fluids through a tube in its stomach every four hours.