More Bird Nests

A couple of years ago I bought a hanging plant to go on my back patio, and a bird built a nest in it. As a result, my plant died. This year, I decided to try again and purchase another hanging plant for the back patio. Wouldn't you know it, there is another nest!

The feeling is truly bittersweet. I'm not sure whether to be upset because my plant may die or happy because we will get a sneak peak into the life of these birds. :-)

We will use this as an educational opportunity. Our first assignment is to figure out what kind of nest it is. It measures 3.5 inches across. Any guesses?