Invading cannibal ladybirds take over Britain's homes

Asian interlopers devour native insect populations and exude chemical that could ruin your curtains

It started with the squirrels – Britain's native reds being ousted by their ruthless grey American cousins. Now another battle is unfolding, one which could be even more catastrophic for an iconic species. Ladybird wars have broken out in the UK – and this time humans are caught in the crossfire.

An explosion in the number of harlequin ladybirds has led to people's homes being infested with the creatures – and threatened native ladybirds.

While the two-spotted and seven-spotted varieties are emblematic of the British countryside, the larger harlequin, first seen in the UK in 2004 and now numbering billions, has become the nation's most abundant species. Rather than feasting on aphids and greenfly, the harlequin also eats lacewings, hoverflies and even other ladybirds.

Dr Helen Roy, head of the national survey, said: "They are spreading at 100km per year, one of the fastest spreading insects worldwide."

The harlequin is a formidable opponent – in particular for the two-spotted ladybird with which it shares an ecological niche. Since the arrival of the harlequins, the two-spotted population has declined by as much as 30 per cent.

Ladybirds are brightly-coloured because they contain defensive toxic chemicals. The harlequin carries a more potent toxic cocktail and is larger than the two-spot. The invaders eat the larva of their British country cousins.

The two-spot, once the second-most common of Britain's 47 species, would not make the top 10 now, Dr Roy said.

The Harlequin, native to Asia, was introduced to America in 1988 and has become the dominant ladybird species on the American continent. The species has invaded most of western Europe, with the UK population growing from a small corner of south-east England to dominate the entire country, as well as parts of Scotland, Wales and Northern Ireland.

They have been known to hibernate in great numbers in dry places like garages and sheds in the autumn.

The harlequin menace is not contained to the insect world. Although they pose no threat to human health, they can be murder on the wallpaper. Last year's wet summer led to an explosion in their numbers and they are now taking winter refuge in houses.

Dr Trevor James, entomologist at the Biological Records Centre: Centre for Ecology and Hydrology, said: "The harlequin has a preference for buildings, and goes into a dormant phase over the winter time. If disturbed, they exude a yellow substance from their knees, which can stain wallpaper."

Noel Shiel, sales technician for rug and upholstery cleaners Pilgrim Payne, which has two Royal Warrants, for both the Queen and Prince Charles, said staining from ladybirds has increased threefold this year.

"There's a real epidemic, they are in almost every home. They seem to be attracted to sash and wooden window frames, and crawl up curtains, leaving orange stains." He said he had seen ladybird damage in some of London's smartest homes, including those in Eaton Square and Sloane Square. The Syrian Embassy had a big problem with ladybirds earlier this year.

Dr Roy does not recommend killing the harlequin, because insecticides could also harm the two-spot. But Tony Halliday, managing director of pest control company Biopest, said he treats ladybird call-outs with a residual insecticide.

And Dr Roy, who currently has more than 400 harlequins gathered in her window frame, believes the insects are here to stay.

It is bad news for the 0.1 per cent of the population estimated to have a phobia of ladybirds. Emma Citron, consultant clinical psychologist from the British Psychological Society, said: "It's not as common as a phobia of spiders, which affects up to five per cent of the population, or dogs, which affects around two per cent. I have helped people with a fear of ladybirds, and there is very little research to suggest it's caused by a bad experience or trauma.

"If someone is trying to tackle a fear, they should start by looking at pictures of ladybirds, using the words 'lady' and 'bird' in their conversation. Next, approach ladybirds, holding them in one hand, firstly far away from the body, then closer.

"People can try to help themselves get over their fear, but in extreme cases - if for example they would turn down invitations to parties in gardens because they are scared - they need help."

A bug's life: know your ladybirds

Harlequin ladybird

First seen in the UK in 2004, the harlequin is now the most populous species of ladybird. Feasts on aphids, other ladybirds, lacewings, hoverflies. Spreading at more than 100km a year, it is rapidly conquering the country. 

Seven-spot ladybird

Goes into leaf litter over the winter months. Historically, the most populous species seen in gardens. Now the second most numerous species, with distribution remaining high. 

Two-spot ladybird

Suffered dramatic decline since the arrival of the harlequin. A decade ago, it was the second most populous species, now not in the top ten of the 47 ladybird species in the UK. Feeds on aphids, shelters in people’s homes over winter months. 

14-spot ladybird

This aphid-feeder yellow ladybird has square spots. A common species, which has seen a rise in numbers this year. 

Kidney spot ladybird

This small, black ladybird with two red spots feeds on tiny insects. Often seen on deciduous trees, and hides in the cracks of deciduous trees over winter. 

Orange ladybird 

This ladybird feeds off mildew. Experiencing a huge distribution increase, thought to be because the warmer, wetter weather in the UK gives it more food. 

Eyed ladybird

Britain’s biggest ladybird, feeds on aphids, most usually found on conifer trees or sheltering in leaf litter over winter. 

http://www.independent.co.uk/environment/nature/invading-cannibal-ladybirds-take-over-britains-homes-6287000.html

British ladybirds in decline – Harlequin moving in

New atlas reveals trends in British ladybird species

July 2011. The first atlas of Britain and Ireland's ladybirds has been published. The atlas is the result of a six year research project by the UK Ladybird Survey, building on data collected over the last two centuries.

The new publication maps all 47 species of Ladybirds in Britain and Ireland, building on thousands of observations from volunteer recorders. The earliest record in the atlas is that of the rare 13-spot ladybird, recorded near Oxford in 1819. The most commonly recorded species, with 27000 records, is the 7-spot ladybird, closely followed by the newly arrived Harlequin ladybird with over 25000 records.

10 ladybirds in decline
Within the atlas there is a detailed analysis of ladybird observations from the last twenty years. The results show that ten ladybird species have significantly declined in this period, whilst five have increased. Distribution maps are provided for each species together with a wide range of supplementary information covering recording techniques, species identification, ladybird parasites, historical aspects, and 194 colour photographs.

Author Dr Helen Roy said, "The atlas data enable us to address many key questions on the fascinating life histories of our 47 ladybird species. As well as being charismatic and popular insects, ladybirds have an important role as indicators of our changing environment."

14 & 10 spot ladybirds in decline

Declining species include the 14-spot and 10-spot ladybirds, which are principally greenfly (aphid) feeding ladybirds coveted by gardeners. Species doing well, and expanding their geographical range, include the Pine ladybird and the mildew-feeding Orange ladybird. In the past the Orange ladybird was a rare species. However it has thrived in recent years, partly by adapting to life on additional types of tree.

Author Dr Peter Brown said, "Ladybirds have captured the imagination of people for centuries. When the on-line UK Ladybird Survey was launched in 2005 we could never have imagined that tens of thousands of people would contribute records. This staggering response has enabled us to assess changes to the distribution of ladybirds over time. In addition, recorders' meticulous observations provide inspiration for new research directions. We hope that people will continue to contribute to this long-term study."

Dr Roy added, "Ladybird interactions with natural enemies, particularly parasites, are intriguing and we hope that this atlas will encourage further recording of both ladybirds and also the natural enemies associated with them."

Roger Hawkins, author of the Ladybirds of Surrey and the foreword to the new atlas, said, "The new Ladybird Atlas of Britain and Ireland offers so much more than distribution maps. Using a mix of photographs and text it helps with the identification of all ladybird species, from the largest to the very smallest, and in all their stages: egg, larva, pupa and adult. There is information on life histories, behaviour, host plants and prey, and details of the enemies of ladybirds, especially their parasites. The atlas is published at a critical moment in the story of ladybirds in Britain and Ireland as our native species, so carefully mapped and studied over recent decades, must now compete with the alien Harlequin ladybird."

The atlas author team included Dr Helen Roy from the Centre for Ecology & Hydrology, Dr Peter Brown from Anglia Ruskin University, Dr Remy Poland from Clifton College and wildlife enthusiast and ladybird recorder Robert Frost.

The atlas can be ordered via all good bookshops or purchased from the Field Studies Council or the Centre for Ecology & Hydrology

http://www.wildlifeextra.com/go/news/ladybird-atlas.html#cr