The appearance of a humpback whale carcass washed up in Mallacoota last week has many wondering what happened to it.
Environment authorities said the animal was a sub-adult female, which ruled out it being the well-known albino humpback Migaloo.
It's not yet known if it is an albino whale at all or if the carcass has turned white due to weathering.
Other questions remain too, including: How did it die? Why did it wash up? And what happens to it now?
How did it die?
Adjunct fellow at Southern Cross University Wally Franklin said there was a range of possibilities for the cause of death of the humpback.
"The whale could have encountered a ship. We were unable to see the upper side of the body and if it has been hit by a ship there'd probably be scarring and damage on the upper side of the body," Dr Franklin said.
"Humpback whales can get parasites within their body and those parasites, if they become too harmful to the whale, can cause death.
"And if a whale is not well for some reason, say it hasn't fed well and it can't move properly, they are subject to getting lice on their bodies, which will ultimately cause them to die as well."
Research officer at the Dolphin Research Institute David Donnelly said it had likely been dead several days before washing ashore and there was evidence of shark scavenging on the body.
"There's any number of reasons for its demise," he said.
He said sometimes younger animals died after leaving their mothers but this whale was beyond the age where that was likely.
Why did it wash up?
Dr Franklin said humpback whales had a mortality rate of 4 per cent.
"Over recent years the birth of the whales have been outnumbering the deaths so we've had a growth in the population, which we now estimate to be in the order of 40,000 humpback whales."
That put the number of deaths around 1,600 humpback whales a year, far more than were found washed up on beaches.
Mr Donnelly said he had seen dead whales floating at sea previously.
"When you spend enough time surveying oceans, by air usually, you do at times come across floating carcasses," he said.
"It's incredibly rare but it does indicate that there are whales and dolphins out at sea that become deceased and float at the surface for a period of time before sinking.
"Animals that might be floating at sea are at the mercy of winds and currents and if the winds and currents are just right and the animal's in the proximity of a coastline, there's a chance it could wash up on a beach."
What happens now?
Victoria's Department of Environment, Land, Water and Planning have said their current plan was to leave the whale in situ to decompose naturally.
Dr Franklin said that could take some time.
"It will take a considerable amount of time for that carcass to decompose," he said.
"It depends too whether it's in the reach of the tides — if the tides come in around the whale, predators might move in and start feeding on the carcass.
"Sharks are a predator of humpbacks, particularly when they have died. We've actually witnessed a whale dying in Hervey Bay and sharks just came from everywhere to consume the body of the whale."
Mr Donnelly said the beached whale was an "amazing opportunity" for science.
"To gather information that we otherwise wouldn't be able to get because obviously we can't go out to sea and sample these animals in the way that you can a deceased individual."
