The National Geographic Guide to Birding in North America
Bird Distribution, Status, and Endemism
S1 E4:
Take account of three further aids for bird identification. See how charting birds' distribution or geographical range provides much useful information about specific species. Grasp the benefits of knowing a bird's status, or abundance vs. rarity, and how status can change. Also study the factor of endemism, where birds are limited to one specific region, and the uses of this information.