For the last couple of nights, around dusk (9:30 pm or so) we’ve seen hundreds of flying insects flying swarm around our townhome’s roof overhang and trees in the garden in North Delta. They move quickly, light briefly on the leaves but do not really stop — they appear to be medium brown, smooth bodied, approx 1/2” long. They fly like flies or bees. Sometimes they would even bump on the window but that doesn’t seem to hurt them. Any idea what they might be? Is it dangerous to children and pets? Thank you so much!