Posted: 19/08/2016 at 08:35
I may be wrong, but my understanding, gleaned I think from the British Ladybird people, is that you should not kill Harlequins, as they are very good at killing a number of pests, and in larger quantities than native ladybirds.
I believe there is also evidence, that the native species is fighting back against the alien.
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You're not wrong P'doc - best advice from naturalists and the RHS is not to kill Harlequins - they are well established here and we will not be able to wipe them out. Their appearance varies widely as do the many varieties of UK native ladybirds, and there is a strong likelihood that people may destroy natives by mistake.
Also, if UK natives do decline in number, we will need the Harlequins otherwise the aphids will take over!
I don't know if others have noticed this, but over the past few years I've seen UK native ladybirds sunbathing in the garden in the spring whereas the Harlequins don't come out of hibernation until the weather is consistently much warmer - maybe there's a niche for both?