The National Geographic Guide to Birding in North America - Season 1 Episode 3 Size, Shape, and Color as Birding Tools

Look first at three physical tools that you can use right away to become a more effective birder. Consider how familiarity with the shape or silhouette of bird families, as well as bird size, aid you in focusing in on exact species. Study the color factors of pigment and keratin, as they produce the dazzling range of bird coloration, and investigate color as an identification tool.