Joe the pigeon might be saved, with the flap over his fate apparently a case of mistaken identity.
Animal welfare group Pigeon Racing Victoria is confident that Joe calls Australia home and is not a racing pigeon that travelled 13,000km from the United States to Melbourne.
It is an issue that has reached the highest levels of government, with acting Prime Minister Michael McCormack warning Joe should "fly home or face the consequences".
The imperilled pigeon appeared to be on death row, with federal quarantine officials threatening to kill the bird over fears it could spread disease.
But Pigeon Racing Victoria is trying to come to Joe's rescue, saying his identification tag is fake.
He is apparently a Turkish Tumbler - a 'show' bird - rather than a racing pigeon who has travelled thousands of kilometres.
The American Racing Pigeon Union has also flown to Joe's defence, posting on Facebook to say the identification band on Joe's leg is counterfeit.
The bands can be bought on auction sites such as Ebay.
"This is not an American bird - he's a bird with a fake ring on his leg," Lars Scott from Pigeon Racing Victoria said.
"He's not a biosecurity risk or anything like that. He's just a lost bird.
"This is stuff we do a lot - we don't want a bird put down for no reason."
Earlier on Friday, Mr McCormack indicated there was little room for compassion on biosecurity laws.
"If Joe has come in a way that has not met our strict biosecurity measures, then bad luck Joe," the acting prime minister said.
"Either fly home or face the consequences."
The Nationals leader's take-no-prisoners stance aligns with predecessor Barnaby Joyce, who infamously threatened to have two Yorkshire terriers euthanised in 2015.
Mr Joyce warned Hollywood stars Johnny Depp and Amber Heard their dogs Pistol and Boo would die unless they "buggered off back to the United States" after dodging quarantine requirements.
An emaciated Joe the pigeon arrived in Kevin Celli-Bird's backyard on Boxing Day, with the initial thinking that he had crossed the Pacific after being reported missing from a race in the US state of Oregon on October 29.
The bird is named after US president-elect Joe Biden and was believed to have hitched a ride on a ship after being blown off course.
Whatever the bewildered bird's provenance, Victorian Animal Justice Party MP Andy Meddick urged the federal government to show mercy.
"Should the federal government allow Joe to live, I am happy to seek assurances that he is not a flight risk," he said.
The agriculture department said an overseas pigeon would not be permitted to remain in the country because it could compromise Australia's food security and wild bird populations.
Australian Associated Press
