After spending the last three months researching stories and legends of this mysterious creature, it’s pretty much impossible not to have developed some opinions on the validity of some of these reported sightings. I definitely believe that people who report seeing large flying creatures are certainly seeing something. However, I’m not entirely convinced that what these people are seeing are in fact extremely large birds. Most of the information about thunderbirds comes from eyewitness accounts. I find it odd that no solid evidence—in the form of bones or other types of remains—has been found that would corroborate stories of extremely large birds, especially ones with capabilities like those reportedly belonging to thunderbirds.
I think a reasonable thing to do when exploring thunderbird sightings is to consider the possibility that people are really seeing massively large birds, but instead of these creatures being undiscovered cryptids of mythical proportions, perhaps they are just species of known birds that witnesses are just vastly overstating in size and appearance.
The reports of thunderbirds are compelling, and these creatures have a long history in both our culture and the cultures of other groups of people that have come before us. There is a large body of research and other work revolving around sightings of these creatures. Some aspects of that research are more credible than others. However, I really think that until we find a “smoking gun,” likely in the form of a mass sighting or the recovery of an actual specimen, the thunderbird will remain simply a legend and a character in some incredible stories.