Mellinus arvensis - Field Digger Wasp
19th September 2007, WednesdayMellinus arvensis, a fly-hunting solitary wasp, is on the wing in numbers at the moment hunting wherever flies hang out. Good places to watch this wasp hunt are bushes of flowering ivy, sycamore leaves, fence posts, walls and particularly mammalian dung!
The photo shows a Mellinus arvensis with a cluster-fly ?Pollenia rudis which it had caught on a grave stone in Fairlight Church graveyard. In fact many of the gravestones had hunting Mellinus on them and the flowering ivy in the Firehills car park over the road also had many hunting Mellinus, in fact there were more Mellinus than their prey. I suspect the wasps were also nectaring from the ivy as well as hunting.
The wasp digs a burrow in sandy soil and provisions the burrow with up-to a dozen flies on which it lays an egg. The burrow can be as long as 40cm and is dug almost vertically down into the soil. Most of the other black and yellow ground nesting solitary wasps have now finished so this is the one you are most likely to see this time of year, although a few of the dead wood nesting Ectemnius wasps are still around on rotten fence posts and fallen dead wood.