Muenster - Germany's oddest couple - a black swan and a bird-shaped pedal-boat that has won its undying love - made a stately departure on Thursday from a German lake as winter approached.

Swan Peter has been stalking the boat, which has a two-metre-high, white, glass-fibre superstructure shaped like a swan, since the springtime on Aasee lake in the city of Muenster. The pedal-boat can be hired by the hour.

Black swans are native to Australia but there is a small wild population in Europe, where animal protection groups feed both the black and white types during winter when lakes are frozen over.

Muenster City Zoo has offered to take in both Peter and its big "friend" for the winter months. The trip to the zoo, navigating along canals and streams, began on Thursday and is to be completed on November 9. Peter dutifully paddled alongside its big hero.

The stay at the zoo may cure Peter's obsession: there are six black swans in the zoo collection.

"Four of them are unmated, so there's hope for Peter yet," said Monika Ewering, a zoo-keeper.

Park visitors said they had the impression that Peter's affection for the boat was waning anyway: in recent weeks, the celebrity swan had spent less and less time trailing it and more and more time accepting food gifts from curious tourists at the lakeside. - Sapa-dpa