Grisly flies!

On a walk in the Chilterns the nectar and pollen from many ivy flowers were attracting flying insects, bees mainly but also another insect. I discovered this was a bristle fly called Tachina fera. It's reminiscent of a bee, due to its colour but definitely a fly! Unlike parasitic wasps this fly doesn't lay its eggs inside the caterpillar, it lays them on the food plants and after hatching, they enter the caterpillar eating it from the inside! Yuk! They're very common across Europe. We found them alongside Grim's Ditch, part of the Ridgeway in Oxfordshire. I'll be looking more closely at Ivy now, while it's flowering, to find more.