MELBOURNE (AFP) - An American pigeon believed to have strayed 14,480km from home had the Australian authorities in a flap on Thursday (Jan 14), after it turned up in a Melbourne backyard having evaded strict quarantine rules.

Melbourne local Kevin Chelli-Bird discovered the emaciated pigeon tagged with an ankle band outside his home on Boxing Day, local media reported.

Dubbed "Joe" after United States President-elect Joe Biden, the bird went missing during a US race in October, Mr Chelli-Bird told the Herald Sun newspaper, and has been tracked to an owner in Alabama.

"The only thing we can think of is, in this race he was blown off course and out to sea, landed on a boat and hitched a ride," he told the newspaper on Wednesday.

"Perhaps he was sick of (US President Donald) Trump and decided to leave."

The pigeon's epic journey sent local media into a flutter, but as the news reached the authorities, the bird became a fugitive for skipping Australia's strict entry procedures.

"As it was not legally prepared for import or imported, the health status of this bird and any others it has been in contact with at its origin and prior to arrival in Australia is unknown," a Department of Agriculture spokesman said in a statement.

"It poses a direct biosecurity risk to Australian bird life and our poultry industry."

It will have to be humanely destroyed if it came from the US without passing through quarantine, according to the department.

Recent press coverage is unlikely to save Joe; Australian officials previously threatened to euthanise dogs belonging to movie star Johnny Depp and then wife Amber Heard, after they failed to declare the pets on immigration papers.

The Hollywood pair managed to save their Yorkshire terriers with a quick flight out of the country. However, as Joe's owner is still to speak up, the feathered fugitive may have to wing it.