Belfast residents woke up Monday morning to what has become a mysterious annual tradition, in the form of gigantic inflatable yellow ducks floating offshore. 

No one knows who deposited the rubber ducky replicas in Belfast Harbor. 

Based on previous experiences, they will likely remain for several days before disappearing as mysteriously as they arrived, according to Scott Smith, operations manager for the Belfast Area Chamber of Commerce. 

“This is the third year that they’ve appeared,” he said. 

Two summers ago, around this time, Smith said the first duck, estimated at two stories tall and emblazoned with the word “joy” on its front, appeared in the harbor one morning, then disappeared a few weeks later.  

Last year, he said, a slightly larger version appeared, adorned with the words “Greater joy.” 

“Yesterday morning, all of a sudden, everyone woke up and there were three ducks,” Smith said. 

The two ducks from previous years had returned, now joined by a third, the largest yet, with “Greatest joy” written on it. 

Since no one knows who placed the ducks there, no one knows what if anything the ducks’ owner is trying to say, but the chamber has come to describe them on its Facebook page as a family.  

The chamber even used a photo of the ducks in this year’s Belfast Visitor’s Guide. 

As to any official response to the ducks’ appearances, Belfast’s harbormaster, Katherine Given, said the ducks are not interfering with boat traffic or serving as a hazard of any kind.  

While she said “we get quite a few” calls inquiring about the ducks, no one has lodged any official complaints, so her office is taking no action. 

Meanwhile, Smith said the chamber gets lots of calls too, all of them good-natured. The cute temporary harbor residents generate a lot of buzz, which he said is not only fun, but good for business. 

“It brings so much joy and it brings a lot of visitors,” he said.