Bird Migration

This post is a question for all the birders who read my blog. Are the turkey vultures migrating right now? This morning we were driving in central Mesa, AZ, and saw a large flock of turkey vultures. They were perched on electric poles, light poles and electric lines. Some were circling in the sky. There were no other birds in evidence. And we don't know of any disaster that would generate lots of dead bodies to attract them. We have never seen more than one of two at a time in the sky over the city, so we wonder if they have begun to migrate north.