Laura is an illustrator based in Denver, Colorado who's big on birds. A quick browse through a rich portfolio of illustrations in her websites will give you an idea.
From a recent post:
"I have sketched some birds (surprise, surprise, huh?). So I googled birds and found some generic types of birds to work on different types of beaks and different birds, really just sketch a little. It's funny these were all done at different times so I didn't realize until just now there's a common thread between them all, they all face the same way. Thing to work on for next sketch session: looking different directions, different perspective on the faces…"