A couple of days ago I saw a spot where maybe seven or eight big hawks were circling. I assumed they were circling over something that was either dead or very close to dead.
Today, I drove by the same spot and counted 40 hawks still circling.
A friend of mine (who is much wiser than me about such things ... okay, about everything) once told me that he does not think that such birds are circling over a carcass. Instead, he feels that they do that over areas where updrafts, perhaps of warmer air, are occurring.
I thought, "Yeah, right".
After some investigation this morning, it turns out he is right.
Below is the official word from the Vulture Society (yes, there really is such a thing). Turns out the birds are probably just sort of lazing around and having fun. Sort of like a weightless chamber for birds.
Would vultures circle a moving object, like a vehicle carrying a dead or dying animal?
Contrary to popular belief, vultures do not circle over dead or dying animals. They soar on thermals of warm, rising air. This allows them to best conserve their energy in flight. After rising on the thermal, they glide as far as possible before they need to gain altitude again.
You will certainly see vultures in the air over a carcass, but their descent is rapid. They will not just hang out in the air looking at it... They want to eat it.
In parts of Asia and Africa, vultures have become very brave and comfortable in the presence of humans. In these areas, they sit around rooftops, markets,and garbage dumps, and have much the same presence among the population as the gulls have among us. In such areas, they will follow carts full of food or garbage.