Birds are a group of warm-blooded theropod dinosaurs constituting the class Aves, characterised by feathers, toothless beaked jaws, the laying of hard-shelled eggs, a high metabolic rate, a …

Dec 17, 2025 · Bird, any of the approximately 11,200 living species unique in having feathers, the major characteristic that distinguishes them from other animals. They are warm-blooded …

Use our Bird Guide to identify birds, learn about the life history, listen to the sounds, and watch bird behavior on video--the most comprehensive guide to Nort

Birds are found worldwide and in all habitats. The largest is the nine-foot-tall ostrich. The smallest is the two-inch-long bee hummingbird. Everything about the anatomy of a bird reflects its...

We believe in the power of birds to ignite discovery and inspire action. Join us on a lifelong journey to enjoy, understand, and protect birds and the natural world.

Many people are curious about the wide variety of birds they encounter, and putting names to those birds is a rewarding experience. We’re here to help with resources to help you, from our …

Discover them all with Birds of the World. Species accounts for all the birds of the world.