How Many?

There are five kinds of birds in this narrow space. Gulls at the top, mergansers just floating in from the right, a great white egret, a tern, and a regular smaller egret. I'm sure they all have more specific names, but I'm not very good at birds. I just get a kick out of all these characters in one place. There was a heron as well, but he remained off by himself and wouldn't get in the group picture. (Feel free to identify these if you can, and thank you.)