Ladybirds may be the nation’s favourite beetle. Instantly recognisable for their cheerful colours and comforting roundness, they are a gardener’s friend and are magical to children.

The name ‘ladybird’ originated in Medieval Britain as a reference to the Virgin Mary, who was often painted wearing a red cloak. One story I read says that people prayed to the Virgin Mary for help after insects repeatedly destroyed crops. Soon after, huge numbers of ladybirds arrived and decimated the pests. The harvest was saved and the ladybirds were called ‘Beetles Of Our Lady’, which became ‘Lady Beetles’, and then ‘Ladybirds’.

Excellent pest control

Ladybirds of all species (27 in the UK) are still excellent pest control, as they happily feast on aphids, scale insects and other ‘plant-feeders’ which, left unchecked, can cause significant damage to plants and crops. They are so effective that you can buy packs of ladybirds online to release into your garden. This is much better than using pesticides.

Unfortunately, because of this reputation, large numbers of Asian harlequin ladybirds were introduced to the USA in 1979 for pest control. Harlequins spread rapidly and are now the most common species in the USA. Having reached our southern shores in 2004, they are now one of the UK’s most common ladybirds too. In fact, in Gloucestershire they may already be the most common.

Harlequins eat the larvae of other ladybirds

This is bad news for our native ladybirds, because as well as aphids, the voracious harlequins are also happy to eat the larvae of other ladybirds. The number of two-spot ladybirds has already declined dramatically since the harlequin arrived.

The other reason the harlequins are tarnishing the reputation of the humble ladybird is because they like to hibernate indoors, often in large numbers. If you have noticed the beetles repeatedly finding their way inside at this time of year, they will be harlequins making a nuisance of themselves, whereas our native species are content to hibernate outdoors.

Their pattern varies

Because they start to invade houses around 31st October, harlequins are known in the USA as ‘Halloween ladybeetles’. In the UK, we don’t yet have a common nickname for the harlequins, but you can easily recognise them as they are larger than our native species and have brown legs. Most commonly they are red with 18 spots, or black with four red spots, but their pattern varies greatly.

So when you see these familiar insects, have a closer look and see what you’ve got. In a way, the prevalence of the invasive harlequins makes our beloved native ladybirds even more special.