Free animal pictures
Sources of free to use / copyleft animal photos online.
Best–usually has the species name:
wikipedia.org
Sometimes has the common name, accuracy unknown:
http://www.freenaturepictures.com
http://animalphotos.info/
http://www.flickr.com/search/advanced/? Set the creative commons checkbox.
US animals, NPS and FWS images are public domain unless indicated otherwise:
http://search.usa.gov/search/images