A weird phenomenon of disembodied feet washing up on Canadian beaches may help investigators understand what happened to alleged Australian conwoman Melissa Caddick.
Several conflicting theories have emerged after the 49-year-old's severed foot, wedged inside a shoe, drifted ashore on Bournda Beach on the NSW south coast – hundreds of kilometres from her Sydney home.
Remains have now also washed up on other south coast beaches – at popular holiday spot Mollymook, at Cunjurong Point near Lake Conjola, and Warrain Beach at Culburra.
They will all undergo forensic testing to determine whether they're animal or human, and if so, whether they provide a match to Caddick's DNA.
Until that happens the strongest clue remains the severed foot, but investigators are struggling to understand how it could have drifted 400km from Sydney.
A senior investigator who spoke to the Daily Telegraph said that the condition of the discovered body parts means Caddick was likely on the run for weeks before her death.
But as the investigation continues, a forensic pathologist has pointed to a weird phenomenon in Canada which could give credence to an alternative theory – that Caddick met her death in Sydney.
At least 21 disembodied feet have washed up along the British Columbian coast, and the adjoining US state of Washington, since 2007.
A decade after the first shoe washed up, a coronial investigation ruled out foul play, finding that the feet came from people who were killed either in accidents or by suicide, and the feet detached during the normal decomposition process.
The feet were usually found in sneakers, which the coroner thought were responsible for both keeping the feet buoyant enough to eventually wash ashore, and gave them enough protection from decomposition to be found relatively intact.
Dr Matthew Orde, a forensic pathologist with the University of British Columbia, told the Sydney Morning Herald that the construction of the modern running shoe provides both protection and buoyancy, enabling the foot to travel greater distances than would normally be expected.
He said the decomposing feet were often found "many, many miles" from where they first entered the water.
"One of the theories is that those running shoes, by virtues of the air pockets in them, are quite buoyant," Orde said.
Interestingly, the investigation is set to return to Sydney's eastern suburbs today, where Caddick was last seen alive.
It is understood police are planning on searching the waters near her home in Dover Heights.
This comes after a senior investigator expressed doubts over whether her foot could have floated 400km to where it was discovered.
Superintendent Joe McNulty, Commander of the NSW Marine Command, who has been working in marine recovery for 30 years, said he has never heard of a case where a body that entered the water in Sydney could float hundreds of kilometres down the south coast.
"Something in the water for that long, say a bit of flotsam or jetsam that washes on to the shore, has got green growth on it," he told the Daily Telegraph.
"At first examination the shoe doesn't appear to have been in the water for three months. The shoe needs extensive analysis to see how long it was in the water. It's a vital clue where hopefully marine biology can provide some answers."
There is also the possibility that Caddick is still alive somewhere, without her foot.
Speaking to Weekend Today on Saturday, University of Newcastle Associate Professor of Criminology Dr Xanthe Mallett pointed out that losing a foot didn't automatically spell death.
"When it was just a foot I would caution against the possibility that somebody is deceased. You can survive without your foot," she said.
Meanwhile, investigators are waiting on DNA confirmation that human remains found on two beaches on the south coast were Caddick's.
Hours after Caddick's foot was discovered on February 21, human remains, including what appeared to a human torso, were found on a Mollymook Beach.
But after undergoing forensic testing, they have been determined to be animal bones, a NSW Police spokeswoman told NCA NewsWire on Monday.
More remains were found by a member of the public on Saturday near Cunjurong Point.
Despite earlier reports suggesting they were intestines, police could not confirm the nature of the grim find, only that they would also be subject to forensic testing to work out whether they came from a human.
Caddick, 49, disappeared on November 12 last year after leaving her home for what her husband believed was a morning run at 5.30am.
She has been accused of swindling millions of dollars out of friends and family through her finance business Maliver Pty Ltd.