Earlier this week I was in Dover, Kent and encountered my first harlequin ladybirds, Harmonia axyridis.
The surprising thing was that I hadn't already seen any. Since it first appeared in the UK in 2004 the species has spread at an incredible rate, and is now known from much of England and parts of Wales.
Because they are an invasive species that threaten the ladybirds native to the UK I collected as many as I could. On Thursday I took these into work not far from Bristol to show my colleagues what they should be looking out for, feeling a little smug that I could do this, until one of the people I work with, Jenna, mentioned that there were some in the window that were the same. She was absolutely right, they were harlequins as well.
As a result I scoured the office building, removing as many as I could find. This resulted in 28, to which I added a further 14 yesterday (Friday).
The question I guess I should ask myself, as an entomologist, is how did I miss these? The simple answer is complacency - I assumed that if they were in the area they would be pretty rare. Despite this I don't think we had any here last year, except perhaps for the odd one or two, so the speed at which they've become established is staggering.
I will continue to remove the ones that I find, but I think it's a lost cause. I think they're probably here to stay.
Sightings of the harlequin ladybird are being collected by the Harlequin Ladybird Survey, and can be submitted online.