A Field Guide to the Birds on the Web
   Links to pictures, sounds, and video of the birds of the world, systematically indexed.
   http://fieldguide.tripod.com/

American Ornithologists' Union Check-list of North American Birds, Seventh Edition
   Official source on the taxonomy of birds found in North and Middle America, including adjacent islands. The full list of bird species (with scientific and English names) is online in HTML, .pdf, and Excel formats.
   http://www.aou.org/checklist/

Avibase
   An extensive database information system about all birds of the world, containing nearly 1 million records about 10,000 species and 22,000 subspecies of birds, including distribution information, taxonomy, and synonyms in several languages.
   http://www.bsc-eoc.org/avibase/avibase.jsp

Bird Families of the World
   Short descriptions and sounds of the world's bird families by Chris Butler.
   http://www.eeb.cornell.edu/winkler/botw/Main.html

Bird Hybrids Database
   Worldwide database compiled from the ornithological literature of birds with two different species as parents. Includes complete references for each species combination. In English, French, and Spanish.
   http://www.bird-hybrids.com/

Bird Lists
   Lists sorted by taxonomy, scientific names, or English names for the world, the ABA area, or the AOU area.
   http://birdingonthe.net/birdlists/

Birdhybrids
   Mailing list for discussion of bird hybrids.
   http://fr.groups.yahoo.com/group/birdhybrids/

Birds of North America
   Comprehensive reference series on North American birds, with information and sample profiles.
   http://birds.cornell.edu/birdsofna/

Birds of North American, Audubon's Watercolors
   Fifty-one images of North American birds from watercolors done by John James Audubon. List can be browsed by common or scientific name.
   http://www.nature.net/birds/

Birds of the World
   Lists of all species with scientific and English names, subdivided by Family. Choice of list based on the Clements or the Sibley and Monroe classification schemes.
   http://birdingonthe.net/clements/

Birds: Wonders of the Sky
   World Book Encyclopedia article covers physical features, behavior, migration, factors which determine range, and how to protect birds. Includes brief facts on individual species.
   http://www.worldbook.com/features/birds/html/

Class Aves
   Provides a definition of birds (Aves) and describes their traits.
   http://animaldiversity.ummz.umich.edu/site/accounts/information/Aves.html

Eggs - A Virtual Exhibition
   The Provincial Museum of Alberta's on-line, searchable, field guide of over 300 bird eggs. Global, with emphasis on birds of Alberta. Includes photos and taxonomic information.
   http://www.pma.edmonton.ab.ca/vexhibit/eggs/vexhome/egghome.htm

Exotic Pet Veterinarian - Avian Anatomy
   Describes the anatomy and physiology of birds for the lay audience, explaining technical terms along the way. Some emphasis on details of psittacines.
   http://www.exoticpetvet.net/avian/anatomy.html

Handbook of the Birds of the World
   Information about the book series that will illustrate and deal in detail with all the species of birds in the world. Site includes tables of contents, sample pages, and publication schedule.
   http://www.hbw.com/

History of North American Bird Names
   Details all the changes in the American Ornithologists' Union Checklists from 1886 - 2000.
   http://members.aol.com/darwinpage/zoo/AOUmenu.htm

Introduction to the Aves
   Scientific background and information on birds.
   http://www.ucmp.berkeley.edu/diapsids/birds/birdintro.html

John Penhallurick's Bird Data Project
   Attempt to build a comprehensive database about the birds of the world, both extant and extinct since 1600.
   http://worldbirdinfo.net/

Mango Verde
   Photos and sounds for almost 2000 bird species; field guide quick indices.
   http://www.mangoverde.com/

Multilingual Bird Search
   Translates world bird names between several languages, including scientific names. Includes photo gallery.
   http://www.knutas.com/birdsearch/

The Internet Bird Collection
   Video library of footage of the world's birds, sponsored by the Handbook of the Birds of the World.
   http://www.hbw.com/ibc/

Virtual Bird
   A collection of bird photographs, videos, and songs from North America and Europe (mainly Finland).
   http://www.virtual-bird.com/

Western Palearctic Bird Sounds
   Links to sound recordings on other sites.
   http://www.ifrance.com/WPBS/