Next time you're on a cruise , if you see a little yellow duck perched atop a picture, or sitting on a hand rail, don't be alarmed. It's probably a 'cruising duck.' A tradition which is said to have been started by an American child in around 2018, it's a scavenger hunt-style pastime popular on cruises.

READ MORE: The key things to know about visiting Paris on the cheap READ MORE: Most beautiful places along the Western Australia coastline It sees avid cruisers hide ducks onboard, which finders can then take and keep. Or they can re-hide their golden find on that ship - or even another. Many are labelled with their 'hider's' details, and finders can also post their duck discoveries online.

 Some ducks are even 'dressed up', such as like sailors, and there are tiny little ducks as well as the ones you'd find in a bath. Fans have even knitted their own ducks, while others give them names, and some cruise experts have even created their own 'branded' ducks. READ MORE: If you're not regularly cleaning your suitcase between trips, you might want to reconsider The global Cruising Ducks Facebook page has almost 280,000 members, while the Aussie one is growing with more than 27,000.

 It's run by Gabrielle from Sydney. Gabrielle - who didn't want to share her last name - has been on more than 50 cruises. She first encountered the trend in America, and set up the Cruising Ducks Australia Facebook page in 2019.

"First time I found a duck I was in America on a cruise in 2017.