Saturday, June 26, 2010

Harlequin ladybirds in Wimbledon

I saw my first Harlequin ladybird in the garden here in Wimbledon on 29/04/2007.

I sent the photo to Peter Brown at http:/ and he confirmed that it was a Harlequin ladybird, Harmonia axyridis. It is also known as the Multicoloured Asian Ladybird and the Halloween Ladybird. He also told me that a colour ladybird identification sheet was available

This species of ladybird was first seen in the UK in 2004 and it has now spread over much of the country. Unfortunately, it appears to out-compete the native species and can even eat them.

I saw others two years later and reported this on 23/7/2009 and sent the next photo:

In the winter of 2009 -2010, which had many days that were well below freezing for several weeks in January, I found many dead Harlequin ladybirds on and inside the back window of the house, overlooking the garden where I found the Harlequins. I have not found any live ones so far this year.

I suspect that the northern spread of this species from Continental Europe may be a feature of global warming. The loss of many over-wintering Harlequin ladybirds suggests that they are cold-sensitive. Britain does not have a 'Continental' climate with wide swings of temperature, but extra-cold winters have significant effects on many species, as suggested here.

Christopher Spry
Wimbledon, London
21:12, 26 June 2010

On 6 July 2013 I found that my Bramley apple tree, in the garden where I had first seen Harlequin ladybirds, was severely infested with their larvae. These were feasting on aphids. There were no apples that year.

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