# A giant undiscovered bird, with a wingspan far beyond any living species, still soars over North America

**No verdict.** Two very different things share the name Thunderbird, and they should not be confused. In many Native American cultures the Thunderbird is a genuine, sacred, and culturally important figure whose reality is spiritual and traditional, not zoological; this file makes no claim about it and treats it with respect as living heritage. The rated claim is separate and modern: that a physical, undiscovered giant bird, with a wingspan of five metres or more, exists (or survives as a relic teratorn) and is behind reports of enormous winged animals. That claim is unproven. There is no specimen, no verified photograph, no feather, and no fossil evidence of such a bird surviving into the present. Sincere sightings are real; the best explanations for them are known large birds, condors, eagles, herons, pelicans, and vultures, whose size is easy to misjudge against an empty sky.

Category: Cryptids & Monsters · Era: 1890s to present · First circulated: Modern cryptid framing dates to an 1890 Tombstone, Arizona newspaper story of cowboys shooting a giant winged creature; the lore was popularized for a wide audience by cryptozoology writers in the 1960s and 1970s, and the elusive Thunderbird photograph legend grew alongside it · Believed by: A niche cryptozoology audience, boosted periodically by reports of very large birds in the American Southwest, the Illinois river country, and Alaska; the missing photograph in particular has a devoted following convinced they once saw it in print
URL: https://theconspiratory.com/theory/thunderbird

## Summary
The Thunderbird sits at the crossroads of two things that deserve to be kept apart. In the traditions of many Native American peoples the Thunderbird is a powerful and sacred being, a real and meaningful figure in living cultures, and nothing in this file is a comment on that. The cryptid claim is a modern, separate proposition: that an actual, undiscovered giant bird, with a wingspan wildly beyond any known species, physically exists over North America and accounts for reports of monstrous winged animals. The lore has memorable anchors: an 1890 story in an Arizona newspaper about cowboys who supposedly shot a huge winged creature near Tombstone, and the famous Thunderbird photograph, a picture many people are certain they once saw of men posing beside an enormous bird nailed to a barn wall, which no one has ever been able to find. This case file separates the documented record (the cultural figure, the newspaper text, the psychology of a photograph nobody can locate) from the rated claim (a living giant bird awaiting discovery). On the evidence, that claim is unproven: no body, no verifiable image, no supporting fossil record, and sightings that fit known large birds seen under conditions that defeat size estimation.

## The claim
That a real, biologically undiscovered bird of enormous size, with a wingspan often given as five metres or more and far exceeding any living species, exists in North America, possibly as a surviving relative of the extinct teratorns, and is responsible for reports of giant winged animals; and, in the strongest version, that a photograph of such a bird was once published and has since been suppressed or lost.

## Origin and timeline
- Pre-contact and continuing: The Thunderbird is a sacred and enduring figure across many Native American cultures, from Pacific Northwest peoples to Plains and Northeastern nations. It is understood as a powerful spiritual being, associated with thunder, storms, and protection, and it appears in oral tradition, ceremony, and art. This is living heritage, not a cryptozoological hypothesis, and it long predates any of the cryptid lore below.
- 1890: The Tombstone Epitaph, an Arizona newspaper, runs a brief and unsourced item describing two cowboys who supposedly shot and killed an enormous winged creature in the desert, with a long body and a wingspan given in improbable figures. The story names no witnesses who can be traced and produces no creature. It becomes the founding text of the modern giant-bird legend.
- 1948: A cluster of reports around Alton and other towns in Illinois describes very large birds overhead. Local papers cover the sightings, and the accounts feed a growing sense that something bigger than any known American bird is being seen from time to time.
- 1960s: Cryptozoology emerges as a self-conscious pursuit, and writers such as Ivan T. Sanderson and, later, others gather scattered giant-bird reports under the label Thunderbird. The 1890 Tombstone story is retold widely, and a durable claim attaches to it: that the Epitaph, or some paper, once printed a photograph of the dead creature.
- 1963: Naturalist Robert R. Lyman and regional folklore collectors publish accounts of giant-bird sightings in the Pennsylvania Black Forest region, adding an Eastern strand to the lore and keeping the topic alive in local tradition.
- 1977: In Lawndale, Illinois, a widely reported incident describes a large bird that allegedly tried to lift a young boy before dropping him. The case draws national attention and is often cited by believers, though descriptions vary and no bird is recovered.
- 1970s to 2000s: The Thunderbird photograph legend hardens. Numerous people, including well-known cryptozoology writers, insist they personally saw a published photo of men, often described as Civil War soldiers or frontier figures, standing with wings outstretched beside a giant bird pinned to a barn. Extensive searches of magazine and newspaper archives never locate it. The gap between vivid, shared memory and total documentary absence becomes a puzzle in its own right.
- 2000s to present: Occasional reports of very large birds continue, often in Alaska and the American Southwest, and are periodically presented online as Thunderbird evidence. Investigations consistently resolve the identifiable cases to known large species; no specimen or verifiable photograph of an unknown giant bird ever materializes.

## The evidence, claim by claim
- Claim: A photograph of men posing with a giant Thunderbird pinned to a barn was once published, so the creature was real and documented.
  Evidence: No such photograph has ever been produced, despite decades of searching by cryptozoology writers, archivists, and enthusiasts through period newspapers and magazines. Many people are genuinely certain they saw it, which is why it is so often cited as a false-memory case, a plausible instance of the Mandela Effect in which a widely shared, confidently held memory has no locatable original. A picture nobody can find is not evidence of a bird; it is evidence of how memory can converge on a vivid image that was never there, or was assembled from separate sources.
- Claim: The 1890 Tombstone Epitaph reported that cowboys shot a giant winged monster, so at least one was killed and examined.
  Evidence: The Epitaph item is a short, unsourced, and unverifiable story typical of the tall-tale journalism of frontier newspapers, which routinely printed sensational filler. It names no traceable witnesses, offers no follow-up, and yields no carcass, no bones, and no photograph. A single anonymous newspaper paragraph from 1890, never corroborated, cannot bear the weight of an undiscovered species; it is a founding anecdote, not a specimen.
- Claim: Eyewitnesses describe birds with wingspans of five metres or more, far beyond any living species, so a giant unknown bird must exist.
  Evidence: Size estimates for an animal seen briefly against an open sky, with no reference object at a known distance, are notoriously unreliable and tend to run large. The biggest living flying birds, the Andean condor, the California condor, the wandering albatross, and the marabou stork, reach spans around three metres, and a condor or large eagle glimpsed high overhead is very easily overestimated. Herons and pelicans in flight, with long necks or bills and broad wings, are also routinely mistaken for something stranger. Sincere reports are consistent with known birds seen under conditions that defeat accurate measurement.
- Claim: The teratorns were real giant birds, so a surviving teratorn could be the Thunderbird today.
  Evidence: Teratorns did exist, and Argentavis magnificens had a wingspan of roughly six to seven metres, which is exactly why the comparison is tempting. But the North American teratorns are known only from fossils and went extinct at the end of the last Ice Age, thousands of years ago. A large, soaring animal that had survived to the present in a well-birdwatched continent would leave abundant traces: nests, droppings, feathers, roadkill, and unambiguous photographs. None exist. An extinct group being genuinely impressive is not evidence that a member of it is alive now.
- Claim: Because the Thunderbird appears in Native American traditions across the continent, it must be based on sightings of a real giant animal.
  Evidence: This misreads what the traditions are. In many Native American cultures the Thunderbird is a sacred spiritual being, meaningful on its own cultural and religious terms, not a field guide entry awaiting zoological confirmation. Treating a sacred figure as circumstantial proof of a cryptid both misunderstands the traditions and appropriates them. The cultural Thunderbird is real as culture; that reality does not translate into a claim about an undiscovered species, and it is not offered by those cultures as one.

## Why people believe it
- The sky erases scale. A bird high overhead, with nothing nearby to measure it against, can look enormous, and honest witnesses genuinely see something big without any reliable way to say how big. The conditions that produce Thunderbird reports are exactly the conditions under which size estimates fail.
- The missing photograph is a perfect hook. A picture that many people are sure they once saw, but that no one can produce, creates a compelling mystery and a sense that proof existed and slipped away. That shape, vivid shared memory plus documentary absence, is itself a known effect, which is why the photo endures even though it cannot be found.
- The name carries borrowed power. Because the Thunderbird is a genuine and awe-inspiring figure in Native American tradition, the cryptid claim inherits a sense of depth and antiquity, as though the sightings must be echoes of something ancient, when the two are separate matters.
- Real extinct giants make it feel plausible. The teratorns actually flew, and Argentavis really was gigantic, so a surviving relative does not sound absurd on its face. The genuine paleontology lends the modern claim a scientific-sounding backbone it does not otherwise have.
- Dramatic single cases stick. The 1977 Lawndale story of a bird that supposedly grabbed a boy is frightening and memorable, and one vivid incident does more to sustain belief than a hundred quiet misidentifications ever could, even when the details do not hold together.

## Open questions
- Where did the Thunderbird photograph memory come from? The image is described too consistently by too many people to dismiss as pure invention, yet no original has ever surfaced. Whether it descends from a real but misremembered photo (of a different animal, or a hoax) or is a textbook collective false memory is genuinely unresolved, and it is a more interesting question than the bird itself.
- What exactly are people seeing in the credible modern sightings, especially in Alaska and the Southwest? Most identifiable cases resolve to condors, eagles, herons, or pelicans, but a residue of well-attested reports is never definitively pinned to a species, which is normal for brief sightings and not evidence of the unknown, though it remains open.
- How large can a living flying bird actually get? The physics of powered and soaring flight set limits, and understanding why the biggest fliers cluster around a three-metre span, and why teratorns pushed past it, sharpens the case against a hidden five-metre bird without needing to invoke a cover-up.

## Sources
- Thunderbird (mythology), Encyclopaedia Britannica (2024): https://www.britannica.com/topic/thunderbird-mythology
- The Truth Behind the Thunderbird Photograph, Smithsonian Magazine (2013): https://www.smithsonianmag.com/history/the-truth-behind-the-thunderbird-photograph-5964102/
- Teratorns: The Largest Flying Birds, American Museum of Natural History: https://www.amnh.org/exhibitions/permanent/birds-of-paradise/teratorns
- California Condor (Overview and Wingspan), Cornell Lab of Ornithology, All About Birds: https://www.allaboutbirds.org/guide/California_Condor/overview
- Argentavis magnificens and the limits of avian flight, Proceedings of the National Academy of Sciences (2007): https://www.pnas.org/doi/10.1073/pnas.0702040104
- Cryptozoology, The Skeptic's Dictionary: https://skepdic.com/crypto.html
- Snopestionary: What Is the 'Mandela Effect'?, Snopes (2016): https://www.snopes.com/news/2016/07/24/the-mandela-effect/

Rated by The Conspiratory, a neutral, sourced encyclopedia of conspiracy theories. Full page: https://theconspiratory.com/theory/thunderbird