When police sirens, ambulance sirens, or firetruck sirens sound on the road, the coyotes in my canyon always yell back for some reason. Why do they do that?
Coyotes, like wolves use howling to keep the group together, to be social and to gather members around alogn with keeping track of other packs to tell them they live in that particular spot. The sirens sound to them like another pack howling, and they are simply howling to tell the "other pack" to bug off.
Coyotes are a hockey team! They don't yell :P Wait wah?
They respond back because the extremely high decibel level hurts their sensitive ears. It's like going from a whisper conversation to a rock concert in seconds.