Police in Canada have launched an investigation after a patron at a Yukon bar allegedly stole the famed ingredient of their signature drink: a mummified human toe.

For more than 40 years the Downtown hotel in Dawson City has served up the sourtoe cocktail, a shot of whisky with a blackened toe – nail and all – bobbing inside. Those who manage to touch the gnarled, severed toe to their lips earn a certificate.

On Saturday a customer took it one step further, allegedly making off with the wrinkled digit after swallowing his drink. “We are furious,” said Terry Lee of the hotel. “Toes are very hard to come by.”

Terry Lee of the hotel displays the toe. Photograph: Alan Solomo/Alamy Stock Photo

The man had apparently boasted of his plans to steal the toe earlier in the evening. He later convinced a staff member to let him try the drink outside of the designated two-hour window known at the bar as toe time. “And this is how he pays her back,” Lee said in a news release. “What a lowlife.”

The tradition claims to trace its roots to the 1920s, when a rum runner preserved his frostbitten, amputated big toe in a jar of alcohol in his cabin. Fifty years later, the pickled toe was discovered by a Yukon native who brought it to the Downtown, where it became a celebrated ingredient in its drinks.

After Saturday’s theft, the hotel contacted the police and began offering a reward to anyone with information. “We fortunately have a couple of back-up toes, but we really need this one back,” said Lee.

It was the newest addition to their collection, donated by a man who had had to have his toe surgically removed. After curing it for six months in salt, the staff had only begun adding it to drinks this weekend, the hotel manager told the Canadian Broadcasting Corporation. “This was our new toe, and it was a really good one,” said Geri Coulbourne.

At least eight other toes have gone missing over the years, some stolen while others have been swallowed. The original toe belonging to the rum runner was accidentally swallowed by a miner after seven years at the hotel, giving rise to another tradition: the hotel’s constant search for toes.

“Got frostbite?” reads an advertisement on its website, which goes on to promise that those who donate toes will be “immortalised in the Sourtoe Hall of Fame”. The hotel said it had received 10 donated toes – big toes are preferred – over the years, including a few that were left to the establishment through wills.

The tradition last made headlines in 2013, after a man seemingly deliberately swallowed the toe in his drink before slapping down C$500 –the fine at the time for anyone who stole or swallowed the toe.

The hotel responded by raising the fine to C$2,500. Staff said they fully intend to charge the latest thief the full fine unless the toe is returned intact. When it comes to tracking him down, they may have caught a lucky break – the man left behind his sourtoe cocktail certificate, meaning police now have his name.