Mission to help whale stuck in Qld lagoon

Marine experts have hit the waters off Cairns in a bid to save a whale stranded in a reef lagoon for at least three weeks.

Wildlife officers have gone to Elford reef in a bid to coax the whale, believed to be between six and eight metres long, to safety.

After studying footage of the animal, which is trapped in a small lagoon surrounded by a maze of reefs, CSIRO's Dr Matt Curnock believes the whale could be an Antarctic minke, rarely spotted on the Great Barrier Reef.

Helicopter pilot Bronwyn Loud was taking a tourist on a scenic flight over the reef last month when one of her passengers noticed the whale. Three weeks on, it's still in the same spot.

"It's not really moving much, just ducking up and down under the water," she told the Seven Network. "It doesn't look like it's going anywhere."

Dr Curnock says wildlife officers who went to the site on Monday tried herding the animal to safety. That didn't work and they're now trying to use the whale's natural curiosity to lure it out into open water.

"I doubt it's able to feed there," he told AAP on Tuesday. "It eats large schools of fish and krill and the like. If it doesn't get out, running out of energy reserves is a real risk for it."

He said a similar incident involving a dwarf minke in 1982 didn't end well. In that case the whale remained trapped for three months and died despite efforts to save it. Its skeleton is now in a Townsville museum.

Dr Curnock said he wanted to confirm the species of whale involved in the current drama.

"It may be an Antarctic minke," he said. "It's pretty rare, but not unheard of, for this species to be on the Great Barrier Reef."

"There was a confirmed sighting of an Antarctic minke back in 2001."

He said wildlife officers would be doing their best not to stress the animal.

"We're certainly hoping this one is going to find its way out soon," Dr Curnock said.