I was wandering through our local used-book store a few weeks ago and stumbled on a treasure: A Sketchbook of Birds, by Charles Tunnicliffe. Our library has a couple of books of his measured drawings, which are amazing in their own right, but I prefer these sketches. They're really lively. All images from Charles Tunnicliffe's A Sketchbook of Birds. Link to the Charles Tunnicliffe Society.