Black and Yellow Mud Dauber

Thank you very much ForestDragon! This was my very first spotting in Project Noah and I am very happy that I now know what they are. They love to come to taste sugar water from the hummingbird feeder. I guess I should let them share sweet water with the hummingbirds....

Neat spotting! This is a type of Thread-waisted Wasp. They are capable of stinging but, like many stinging insects, they are most likely to sting only in self defense. If you respect them and their space you should be fine.

The nests they build look like this:
http://bugguide.net/node/view/346108