A thunderbird, considered a myth, is a large bird like creature generally identified with Native Americans. Reports of these birds go back centuries, fossils have been found of giant birds with wing spans of 50 feet.
April 10th 1948 three people in Overland IL spotted what they thought was a plane, then they saw the wings move and realized it was a huge bird. A few weeks later a father and son spotted a very large bird in Alton IL. They said it flying at 500 feet and cast a shadow the same size as a small plane.
St. Louis MI residents wrote letters to the mayor to do something about these giant birds.
July 25th 1977 Lawndale IL three boys were playing when two large birds flew towards them and chased them. Two of the boys got away, the third was not so lucky. Ten year old Marlon Lowe was lifted 2 feet off the ground and carried some distance by one of the birds. The boys described what most believe to be an Andean condor, but a condors talons are not strong enough to lift heavy objects.
2002 Alaska a bird with a wingspan of 14 feet was reported. Many believe this was a Stellers sea eagle as there were some reported to be in the area.
Cryptozoologists believe thunderbird myths are based on sightings of real birds with a mistaken assessment of size.
Skeptics have claimed that such a large bird could never fly. There has been several large flying creatures such as the Arcentauis Manificens with a wingspan of 23 feet or the Quetzalcoatlus with a wingspan of 40 feet just to name a few.
Cryptozoologists say the thunderbird was associated with storms; the thunderbird would follow drafts to stay a flight. John Keel claims to have mapped several thunderbird sightings and found that they correspond with the storms moving across America.
Angelo Capparella, an ornithologist, says it is highly unlikely of such undiscovered large birds, especially in North America.
No one has ever produced a real photo of a thunderbird.