A rare sighting of a white humpback whale off the coast of Australia raised speculation whether it was the famed Migaloo on his seasonal migration to the north.

The white whale was spotted by a media helicopter along the Gold Coast and was filmed by whale watchers Monday. It was initially believed to be Migaloo, Australia's beloved and most well known albino whale, but as experts took a closer look, they discovered it was not the iconic whale, CBC News reports.

"We don't have any photographs or past photographs to make an absolute identification, but going from the size this is a much smaller animal than Migaloo," Long said. "I have seen Migaloo and I have seen this other animal before," he told ABC.

Long said the recently sighted white whale was 5 meters smaller than Migaloo, which is a full adult male. He also described the smaller whale as "robust" with a good swimming pattern.

Oskar Peterson, founder of the White Whale Research Centre and the person behind the Migaloo Twitter account, believes it may not be Migaloo.

"He seems to be very shining white, while last year he (Migaloo) had yellow colouring markings on him," Peterson told Mashable.

He said that Migaloo has scars on his back after he was run into by a trimaran last year. Peterson also pointed out Migaloo's unusual hook, which he did not see on the videos and photos of the recently sighted white whale. He concluded the white whale could be Migaloo Junior.

"We know there were two white whales born the size of Migaloo on the east coast in the last four or five years. We also believe there is one that cruises up the west coast of Australia but we don't have photographic evidence of it," Peterson said.

A Twitter user shared a video of the white humpback whale.

Another video of the white whale sighting was uploaded to YouTube by user James Chambers. The whale was seen in Hastings Point, NSW.