If it is true that ladybirds love to fly away home, then 720,000 of them will presumably be delighted to find that their new domiciles are in the funky Lower East Side of New York. Even better, once there, it will be their duty to make like other New Yorkers and embark on a high-protein nutrition plan, although their diet will feature more aphids and fewer egg-white omelettes than the average Manhattan socialite’s. However, in a city that is neurotic about etiquette, the red-and-black ladies must make sure not to exploit the generosity of their hosts, or face the consequences.

Because bright ideas to combat pest problems with natural solutions do not always work. The rapacious Indian mongoose was introduced to Hawaii to eat rats and snakes. Perhaps understandably, it grew tired of this diet and moved on to turtle eggs and farmyard chickens. The charming beast also, it transpires, spreads rabies. Studies have consistently shown that if there is one thing a host cannot tolerate in a guest it is rabies, but mongooses have no manners. Australia is similarly bothered by inconsiderate visitors. The cane toad was introduced by farmers to eat pests, which it failed to do. But it did eat everything else and, having no predators, has thrived. The toads are now reviled and persecuted by teams of scientists hellbent on sterilising them.

The ladybird has an advantage over the toad, being small and cute rather than large and warty. But plagues have been unpopular since biblical times, and if ladybirds multiply too vigorously, they may find that red and black spots fall swiftly out of fashion in New York this autumn.