EMERGENCE OF THE ENEMY WITHIN

Three species of ladybird have recently colonised Britain. Two have done so almost unnoticed: the Bryony ladybird, which feeds on plant matter, and the tiny and inconspicuous Brown ladybird. But the third species, the notorious Harlequin, has done so with far greater fanfare. In the middle of the opening decade of the 21st century, people began to notice groups of large and often very variable-looking ladybirds in their homes and gardens. Some were black with red spots, others orange or yellow and some were red, leading to the reasonable assumption that they were several different species. Yet they were all just one: the now notorious Harlequin ladybird. This species, originally from Asia, was introduced to North America in the 1980s to control aphids, but soon spread out of control. They took some time to reach western Europe, probably on imported plants, but in 2004, the first specimens were recorded in Britain. Since then, they have become very common, taking just a decade to spread through virtually the whole of the UK mainland, and in 2012, they reached the northernmost archipelago, Shetland. As a voracious predator, often feeding on other ladybird species, they now pose a major threat to the UK’s native ladybirds. They also feed on the eggs and caterpillars of butterflies and moths, and out-compete native ladybirds for food. It is thought the recent decline of the once common Two-spot ladybird may be down to the Harlequin’s arrival.