If it looks like a bumblebee, and acts like a bumblebee, then it must be a bumbl….oh, hang on…. I spotted this insect feeding on a thistle when I was out at Máméan last month. I thought it was a bumblebee at first but there was something a bit strange about it. Turns out it is a hoverfly that is something of an imposter. There are ten such hoverfly imposters in Ireland (and the National Biodiversity Centre has published a guide here). I think the one above is a Eristalis intricarius, because there is a loop in the wing vein and has a slightly pale hind leg.
I didn’t notice it until I looked at the photo, but the hoverfly is not along on the thistle head – I can see a few shieldbugs, as well as another green insect that I can’t identify (just under the purple flower).