Map of the Week: Alien Invasion
As I stumbled down the stairs this morning, I discovered I had been invaded by aliens. In the interests of science, I pulled out a camera and took a photo of them for you.
It is that time of year when the ladybirds move in, squeezing under windows and around doors hoping to find warm and safe living quarters to see them through to Spring.
But my snap of just a few of the uninvited guests reveals that this is not a case of British homes for British bugs.
These are Harlequin ladybirds, unwelcome foreigners who are making life increasingly precarious for the indigenous coccinellids.
Fresh off the presses, my map of the week this week documents the latest information on the spread of the Harlequin from its first known arrival in Britain in 2004. 
Native to Asia, Harmonia axyridis (Pallas) was widely introduced into Europe from 1995 as a biological way to control aphids. (Will we ever learn!) Sold by various biological control companies in France, Belgium and the Netherlands, it was also intentionally released in at least nine other countries.
While the black and red harlequin has a suitably diabolic colour-scheme, don't be fooled. The more common type of harlequin is orange with black spots - easily mistaken for our native types.
It has spread very rapidly and is now regarded as established in thirteen European countries including, most recently, Norway and Sweden. But their continued spread in the UK spells bad news for our common native two-spot and seven-spot varieties.The Harlequins eat their babies and their food supply.
The map confirms the spread north of the Harlequin, but this year's real change will probably be far more obvious after the reports of sightings in the next week or so are recorded.
In the United States the Harlequin is known as the 'Halloween Ladybug' because it makes its presence felt at this time of year.
The mapping of the Harlequin is perhaps the first time a species has been tracked from its arrival in a country. If you see one and want to help the scientists keep tabs on the invasion, details of the project can be found .
Publication of the new Harlequin map coincides with the ³ÉÈË¿ìÊÖ's Alien Invaders week. The stories of Japanese knotweed, Chinese mitten crabs and American crayfish will be narrated across the output in the next few days. The cost to the taxpayer and business of these invaders is significant - yet another example of how globalisation is changing the way we live.
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