Thunderbird — Native American Legend Backed by 19th-Century Settler Sightings of Enormous Flying Creature

The thunderbird is one of the most enduring cryptids in North American tradition — a massive, eagle-like or condor-like creature reported to have a wingspan far beyond that of any known bird, sometimes estimated at 20 to 50 feet. It appears in the mythologies of numerous Native American nations across the continent and was reported by European settlers throughout the 19th and early 20th centuries.

In April 1890, the Tombstone Epitaph newspaper of Arizona reported that two cowboys had shot and killed an extraordinary bird with a wingspan of 160 feet and a serpentine body, dragging its carcass into town for viewing. Whether this specific account was apocryphal or factual, it reflects a broader tradition of settler-era thunderbird encounters across the Southwest and Great Plains.

Sightings persisted through the 20th century. In 1948, a series of reports from Alton, Illinois described a creature with a wingspan of 25 feet flying low over the city. In 2002, multiple witnesses in rural Alaska including a pilot reported seeing a bird with a wingspan comparable to a small aircraft. In 2007, a woman in Southwest Pennsylvania photographed a large unidentified bird.

Cryptozoologists have proposed that the thunderbird could represent a surviving population of Argentavis magnificens, the largest flying bird in the fossil record with an estimated wingspan of 23 feet, or of large pterosaurs. No body has been produced and no photograph has been authenticated.