If you ever read Indian myths, then you heard of the thunderbird. It is described as a large bird, capable of creating storms and thundering while it flies. Clouds are pulled together by its wing beats, the sound of thunder is made by its wings clapping, lightning flashes from its eyes when it blinks, and individual lightning bolts are made by the glowing snakes that it carries around with it. In masks, it is depicted as many-colored, with two curling horns, and, often, teeth within its beak. The Lakota name for the Thunderbird is Wakį́yą, a word formed from kįyą́, meaning “winged,” and wakhą́, “sacred.” The Kwakwaka’wakw has many names for the Thunderbird and the Nuu-chah-nulth gave it the name of Kw-Uhnx-Wa. The Ojibwa word for a thunderbird that is closely associated with thunder is animikii, while large thunderous birds are known as binesi.
Although associated most of the time with the Plains Indians, the Thunderbird was also known to the Algonquin-speaking peoples. However, like most Native American cultures on East Coast (except maybe Iroquois), little is now known of their beliefs.
In regards to the Thunderbird, this much is known: This fearsome being that resembles a winged man or an immense bird causes fear and dread. The myths tell that it is known to actually kill and eat humans from time to time.
There once existed a gigantic bird in North America. Called the Teratornis Merriami, it stood five feet tall and had a wingspan of twenty-four feet and had the long narrow beak of the predator bird, too. Bones of this bird and humans have been found in the same areas together. Maybe the ancestors of the Native Americans today killed these giant birds for their feathers or myths of the Thunderbird arose due to the birds kidnapping their children and stock.