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'Giant' ladybirds head for Norfolk
The Harlequin ladybird eats other ladybirds and will threaten to wipe out the traditional Norfolk insects.
SAM EMANUEL
14 July 2009 23:36
Lofts and sheds in Norwich might soon be packed full of "giant" ladybirds - but although they are threatening our native species, experts are urging people not to kill them.
Norfolk's population of harlequin ladybirds, which originated in Asia and arrived in Britain during the past decade, is booming thanks to the recent surge in aphids and lack of natural predators.
The most common colour forms are black with two or four orangey-red blotches, or red with up to 21 black dots. At between 6mm and 8mm long, the harlequin is bigger than native ladybirds. Most native species, with black wings and red blotches, are between 4mm and 5mm long.
Dr Ian Bedford, research entomologist at the John Innes Centre, said: "With the recent surge in aphid infestations, we're expecting to see an increased number of harlequins in this region soon. It has been quite phenomenal so far. I was looking at some stinging nettles the other day and there were literally thousands on there - I couldn't believe it. They might also become a problem in the autumn when they begin to congregate in houses to sit out the winter.
"They are also attracted to white walls of houses.
"They feed on a much wider range of insects than our native ladybirds, and when the aphid population starts to decline again I think they will start eating anything that happens to be in the area where the aphids were.
"For example, on rose bushes, if there are no aphids, they may eat the larvae of our indigenous ladybirds, hoverflies, and lacewing larvae. But nature has an amazing way of restoring the natural balance, and parasitic wasps are now beginning to feed on harlequins.
"People mustn't go and kill them - they can easily get mixed up with some of the other ladybird species we have got, so it may do more harm than good, and there are so many about now that it would be pointless to try and kill them."
The harlequin ladybird was used by farmers in Asia as a bio-control agent, where the ladybirds would eat insects to stop them destroying crops. In recent years they have been introduced to Europe, and their population has grown and spread to England.
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The picture with this article from my local newspaper, shows a ladybird like the one I caught the other day, mine had two lighter spots tho, more creamy than orangey, but otherwise just the same. I put it back outside so hope it will just eat the aphids and nothing more.
Lizx
Apologies to those who don't like me copying articles from my local newspaper etc - Not !
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