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Invasive Ladybird Threatens UK Species

A new ladybird has arrived in Britain. This is not just any ladybird, this is the Harlequin ladybird (Harmonia axyridis), the most invasive ladybird on Earth.

Harmonia axynids succinea
© Mike Majeurs

There are 46 species of ladybird (Coccinellidae) resident in Britain and the recent arrival of the Harlequin ladybird is a major threat to many of these. It is also a deadly threat to many other insects, including butterflies and lacewings. The Harlequin ladybird is an extremely voracious predator that easily out competes native ladybirds for food. It is so successful that while native ladybird numbers dwindle the Harlequin ladybird flourishes. When their preferred food, of green fly and scale insects, is not available the Harlequin readily preys on native ladybirds and other insects such as butterfly eggs, caterpillars and lacewing larvae. Harlequin ladybirds are also partial to soft fruit, particularly pears.

Introduced from Asia into North America for biological control of aphids on crops, the Harlequin ladybird has swept across the US, quickly becoming by far the most common ladybird. In the last decade its catastrophic increase in numbers has threatened native North American ladybirds and other aphid predators, many of which are plummeting alarmingly as the Harlequins consume their prey. The Harlequin ladybird is also partial to overwintering inside houses in huge numbers where their defecations destroy upholstery, curtains and wallpaper. Despite this unwelcome and well-publicised take-over of America by the Eastern invaders, Harlequin ladybirds are still sold in continental Europe by biocontrol companies, and it now roams across France, Belgium and Holland, with numbers soaring annually

Harlequin Ladybird
(Harmonia axyridis)
- Adult & Pupa
© Bev Wigney
Crocodile Pbase Gallery

Andrew Whitehouse of Buglife comments, "It is staggering that a species like the Harlequin Ladybird, which has been well documented as being highly invasive and devastating to native invertebrate species in the US, is still on sale in the US and in continental Europe as a biological control agent. This current situation illustrates the inadequacies of current regulation on the release of non-native organisms for the purpose of pest control.”

Buglife believes that the issue of invasive species should be taken very seriously, action is required by the Government at three levels:-

To if at all possible exterminate the Harlequin ladybird.
To join American research efforts to find a long term solution to the problem.
To work in the EU to secure better biosecurity for the continent.

Invasive Ladybird Threatens UK Species

Monitoring ladybirds across the country has never been more important. Please visit the Harlequin Ladybird Survey to find how YOU can help.