Swarm of midges?

Swarm of midges?

Observation - Swarm of midges? - UK and Ireland. Description: At first I thought it was smoke, then starlings, then bees. They were at the top of an ash tree, so about 10 metres up. It was very still and hot and the swarm moved around like smoke but still fixed on a spot over this one tree. Too high for ants sure

At first I thought it was smoke, then starlings, then bees. They were at the top of an ash tree, so about 10 metres up. It was very still and hot and the swarm moved around like smoke but still fixed on a spot over this one tree. Too high for ants surely? Chironomidae?