I have been watching these guys for a few weeks, now. They invariably hang out on pine trees almost always facing downward. I couldn't figure out why they constantly flew off and then landed back close to where they took off, kinda like dragonflies with their favorite perches. As I watched one recently, it took a long-legged fly and commenced to chowing down. A light bulb went off. They were carnivorous! As well, the fire and other ants living in and on the pines don't seem to bother with them but will chase down everything else.