A new ladybird has arrived in Britain. But not just any ladybird: this is Harmonia axyridis, the most invasive ladybird on Earth.
Harmonia axyridis, which is variously called the Harlequin ladybird or the Multi-coloured ladybug, is a deadly threat to a suite of insects, including butterflies, lacewings and many other ladybirds.
Introduced from Asia into North America for biocontrol of aphids, the Harlequin has swept across the States, becoming by far the commonest ladybird in less than a quarter of a century since establishing there, and now Canada is seeing a similar spotted tide. In the last decade its catastrophic increase in numbers has threatened endemic North American ladybirds and other aphid predators, many of which are plummeting alarmingly as the Harlequins consume their prey. Despite this unwelcome and well-publicised take-over 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
Now, it is here! 
On Sunday 19th
September, Mr Ian Wright found an ‘odd’ ladybird in the garden of the White
Lion pub, in Sible Hedingham, Essex. The ladybird was identified by Dr Michael
Majerus of the Genetics Department, Cambridge University, an international
ladybird expert.
Dr Majerus, who admits to “having an inordinate fondness for ladybirds” said, “this is without doubt the ladybird I have least wanted to see here. Given its proximity in Holland, I knew it was on its way, but I hoped that it wouldn’t be so soon. Now many of our ladybirds will be in direct competition with this aggressively invasive species, and some will simply not cope”.
The Harlequin ladybird not only threatens other insects: in America it is also in conflict with humans. September sees many houses inundated by hundreds of thousands of these beetles seeking places to pass the winter. Harlequins also feed on fruit juices as they fuel up for the winter and fruit-growers are finding that they blemish many soft fruits, reducing the value of the crop. Indeed, so fond are they of grapes, that wineries have reported that the huge numbers of this ladybird among the harvested grapes, taint the vintage because of their acrid defensive chemicals. If this was not enough, reports of Harlequins biting people in the late summer as they run out of aphid prey, are escalating.
In 
North America and continental Europe, it will be
difficult to control this invasive species, as numbers are already so great.
However, in Britain we may still have time. Dr Majerus urges anyone who finds
this ladybird to send it to him with precise details on when and where the
ladybird was found. Although highly variable in its colour and pattern, none
of the forms are easily mistaken for any British ladybirds. “It is critical to
monitor this ladybird now, before it gets out of control and starts to
annihilate our own British ladybirds” he says.
Quotes above are from a press release from:
Michael Majerus
Department of Genetics, University of Cambridge, CB2 3EH
Tel: 01223 356372 or 01223 276190<
Mobile: 07973 290059
Fax: 01223 333992
e-mail: m.majerus@gen.cam.ac.uk
I hope that you will excuse this blanket letter, but as you
may imagine, the ladybird group have been inundated with reports of odd
ladybirds from across the country. Many of these have been of less common
native species, or unusual forms of native species. Many have also been
of ladybirds seen earlier this year. Obviously, as the Harlequin ladybird
is such a variably patterned ladybird, it is difficult to make firm conclusions
of the identity of a ladybird without a picture or the ladybird itself.
However, although thankfully there have been many false alarms, there has also
been a significant number of Harlequins.
For information, you might like to know that we now have confirmed records of
the Harlequin from Battersea, Wandsworth, Clapham, Tottenham, Folkestone,
Sevenoaks, Ipswich, Newmarket, Canterbury and East Sussex.
Further information on H. axyridis is available on:
Thanks for your interest and good spotting.
Mike Majerus
© 2004 Suffolk Naturalists' Society
used by kind permision.