The police sealed off an area with yellow crime-scene tape and launched a boat, with one officer carrying a noose-like device; but the reptile vanished in the 9ft depths.

Five days later, it was captured by the Florida 'gator-wrestlers Mike and Tina Bailey using a torch, a canoe and their bare hands. It turned out to be a South American spectacled caiman, a type of crocodile that could have grown to 8ft. This one was about two years old, and was christened Damon by the park director Henry Stern. "He will be given a good home," said Mr Bailey. "He will not be turned into a purse." Crocodilians have turned up in New York before; in 1997, for instance, a 3ft-long alligator was captured in Kissena Lake in Queens - presumably when it grew too large for its owner's bathtub.

New Yorkers were startled on July 9 when hundreds of manhole covers were plastered with stickers reading: "Warning: sewer lizard extermination in progress. Stay clear." Meanwhile, cards were handed out to the public in busy areas.

The curious were directed to a website, which announced that fumigation was needed to kill 10ft-long, 450lb lizards (Crocodilus hemizibecus gigantus) that had mutated from reptiles flushed down lavatories in the 1960s, when the cute creatures became too big for domestic pets. The website asserted that "there were 30,575 cases of sewer lizard encounters with Americans" between April 1998 and May 2001. The whole thing turned out to be a promotional hoax by a television channel. While the notion of alligators in New York's 976 miles of sewers is generally dismissed as an urban myth, dozens have, in fact, been found and killed in the city over the years. In 1935, Teddy May, the superintendent of the New York sewers, descended below ground to prove that the stories were nonsense, but was astonished to encounter many specimens more than 2ft long in the smaller pipes. Rat poison got rid of some while others were flushed into the faster-flowing channels of the main pipes, where they drowned or were washed out to sea. A few were picked off with rifles.

Five more were caught in the sewers of New Rochelle, New York, in 1938 and there were further sightings in 1948. By the time Thomas Pynchon wrote about them in his novel V (1963), they had also been spotted in Yonkers.

It's been a fine summer for misplaced crocodiles. A German cyclist urinating in some bushes next to the Rhine near the town of Ketch on June 22 told police that he found a 5ft crocodile lying on a log. He threw some earth and it hissed at him before swimming off. A helicopter was sent up and boat patrols organised after a second sighting further downstream five days later. Nothing was found apart from a joker's carved wooden dummy, but a day after the search was called off there was a third sighting.

On June 25, a group of children found a dead 2ft crocodile in a lake called Lilla Le in Dalsland, Sweden. The police, who took it away, had no idea where it had come from. On July 19, Austrian firemen caught a 2ft crocodile in the Danube canal right in the middle of Vienna. It was taken to the Schoenbrunn Zoo.

On June 26, an unexpected speed bump on the access road to Cairns Airport in Queensland gave a taxi driver and his passenger a fright when it turned out to be a 7ft crocodile soaking up the sunshine.

Paul Sieveking is the editor of Fortean Times.

(Thanks to Sewerfriend Julia Solis for this item.)