He was captured on a mobile phone camera at around 8am on Tuesday morning off Green Cape in New South Wales, and though the image is "not the best" it was confirmed as a sighting by the founder of the White Whale Research Centre, Oskar Peterson.
Mr Peterson told ABC News Australia that the sighting matched Migaloo's known migratory patterns off Australia's east coast.
He said that while the whale is almost unique, watchers have a "good" opportunity to see him if they move quickly.
"I know from Byron Bay to the Gold Coast, the last week of June to the first week of July is that two-week window where he'll go past," the expert said.
"Now's the time down there in Eden (in New South Wales), down the south coast and Illawarra to get out there over the next couple of weeks, you'll have a good chance of spotting him."
Migaloo. Photo / File / AAP
Mr Peterson said it was difficult to miss Migaloo when he goes past - but that it isn't every year he makes a public appearance.
"He's been around for quite a while and he cruises up and down the east coast of Australia every year, but some years he goes missing in action so to speak," Mr Peterson said.
"He sort of glows in the water like a fluorescent blue. He's quite an amazing sight."
Migaloo's movements have been documented closely over the years, and in 2004 sloughed skin samples collected by researchers gave a us clear genetic fingerprint - and showed that he is definitely male.
He is suspected to be an albino whale, though experts say the evidence on this point is not "definitive". His name comes from Aboriginee for "White Fella".
Migaloo was thought to be unique among humpbacks until in 2011 whale watchers spotted a similarly all-white male juvenile. Appearing in the same larger group as his famous predecessor, the calf was unofficially dubbed Migaloo Junior. It is unknown whether the two whales are related.
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- UK Independent