Biologists in Muenster, in north-western Germany said that a black swan has been smitten with a swan-shaped paddle boat. They said the Black Australian Swan has been showing all the typical signs of love for its species, circling the plastic boat, staring endlessly at it and making crooning noises.

The unusual behavior of the swan has compelled authorities to move the bird and the boat to a zoo.

It was also reported that the swan now refuses to fly south for its annual winter migration without his mate.

Park keepers say that "Black Peter," as the lovesick swan is called, refused to leave the boat on the Aasee Lake. The boat is also scheduled to be taken out of the lake during the cold weather.

Peter Overschmidt who owns the boat has agreed not to lock his boat away for the winter.

He said, "When you see how Peter circles the swan boat you know there could be no other option, it's the center of his life."

Fortunately for the bird, the Allwetter Zoo has agreed that both Peter and the boat could spend the winter on their pond near the elephant enclosure, which is more protected from the elements than the lake.

Zoo director Joerg Adler said, "This arrangement could go on for ever because the animal now firmly believes he has found a partner for life."