When Sandy started her search for a mate, Peter must have looked quite a catch: almost 6ft, no beak but an impressive moustache, fluent guttural German rather than an irritating high-pitched squawk. Put him in a tux, she must have thought, and he would do — a man to lay eggs with.

The tale of Sandy, 14, a South African penguin, and Peter Vollbracht, 47, a zookeeper, is a saga of enduring love, separation and fidelity that has captivated Germany — a parable for a society troubled by high divorce rates and marital breakdowns.

Penguins are till-death-do-us-part monogamous and as a result are very selective when choosing a mate. Yet soon after arriving at Münster Zoo in northwest Germany at the age of 2, Sandy had Mr Vollbracht in her sights.

There must be something about German zookeepers.

The celebrity polar bear at Berlin Zoo, Knut, became attached to his keeper Thomas Doerflein, who strummed Elvis songs while the cub was in intensive care. Mr Doerflein hand-reared the bear, rescued him from the compound in Berlin zoo, helped him through teething, taught him to swim and to dribble a basketball. Mr Vollbracht went down a similar route. He and Sandy became inseparable. When the keeper took the zoo’s 80 penguins for their daily waddle, Sandy would skip to the front so she could walk next to her man.

Despite what the advertising world may have you believe, it is extremely difficult to pick up a penguin. If humans get too close they think they are under attack, and hack at them with their sharp beaks. But Sandy allowed Mr Vollbracht to carry her around. Soon she became Germany’s most strokable penguin. School classes, lovers seeking inspiration, even clinically depressed patients advised that man-to-bird touching could be helpful, all flocked to the zoo. Inevitably, the two appeared on television and in films.

Penguin Overboard, a made-for-television drama, features the kidnapping of Sandy; her rescue brings together a female zoo director and a shabby-looking but warm-hearted keeper. For some Germans at least, Sandy seemed to possess Cupid-like match-making powers.

But then Mr Vollbracht slipped a disc and was off work for two months. Sandy must have assumed he had died and she was therefore no longer bound by her penguin vows. She found an adequate mate, Tom — no moustache, no gumboots, but at 5 years old, significantly younger. Last year Tom and Sandy started a family, and had two chicks. “Ultimately it was better for her to live a normal penguin life,” said Mr Vollbracht, who is married with a human wife and two children.

Six weeks ago Tom died. The chicks were fostered out, and Sandy, back on the singles market, immediately took up with her old flame.

“After Tom died she was looking for someone and I was there,” he said. One day Sandy will have to find another penguin, but for now she is happy with Mr Vollbracht.

“We can’t find her a partner,” said Mr Vollbracht. “It’s her decision.”

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