Learned something new today: spotted a bird near the lake in our backyard; no idea what it was. Shaped like a shorebird, dark above white below, and constantly moving its butt up and down.
For an experienced birder, looks like that's all the info needed to make the ID: Spotted Sandpiper.
I bought the Sibley field guide recently, and this was the first time I used it to ID. I have to say, it was easier than the Audubon guide. While both mention the bobbing motion, it was easier looking at the shorebird illustrations gathered together in Sibley's, making guesses as to the likely suspects, then jumping to the more detailed description/illustration pages.
The birds were pretty forgiving, and it was easy to get within 40 feet of them to make a good visual ID on them. So, apparently, the Spotted Sandpiper is the only one with the "teetering" motion? Then, IDing them is easy even from a great distance with no view of detailed markings.
Edit: woops, meant to put this in General Discussion.
