The legend of Bigfoot has persisted for hundreds of years. However, no one’s yet been able to present solid proof that the urban legend actually exists. But Jeff Meldrum, an anatomy and anthropology professor at Idaho State University, thinks proof could come along any day now.

Meldrum, who specializes in ape and hominid locomotion, has been studying Bigfoot footprints for years. In a recent interview with media site LadBible, he said that what he’s seen is compelling enough to convince him that Bigfoot does exist. In past interviews, he’s described some of the footprints he’s seen (and made casts of) as being 14 to 15 inches in length, with evidence of human-like midfoot arch. In some cases, he’s even been able to make out skin whorl patterns under the toes that are strikingly similar to that of human feet—just way bigger. With that kind of evidence out there, he says, it’s just a matter of time before a backcountry recreationist stumbles upon something even bigger.

“At some point a hunter is going to shoot one, or a semi-truck is going to hit one on a rural highway, something like that. Or some spelunker maybe will serendipitously stick their head into a hole in the ground and come out with a skull or a jaw or a leg bone or something of enormous proportions,” he said in his LadBible interview.

Medrum added that he believes the Bigfoot population in North America may number in the thousands. It’s true that Bigfoot sightings have been recorded across a wide geographic range. This could indicate that Bigfoot is a habitat generalist capable of living in a variety of environments. If that were the case, then there could be enough habitat connectivity to support a relatively large population.

While some people think we should leave Bigfoot alone — and others say it’s statistically far more likely that Bigfoot is actually a black bear — Meldrum believes it’s worth continuing the search. If Bigfoot is out there, it’s probably endangered. Finding the creature could allow humans to better protect it from habitat loss and other threats. With other rare species, scientists study population movements to inform conservation measures. It follows that we should take the same approach with Bigfoot, Meldrum says.

So, after hundreds of years of searching, why haven’t we found Bigfoot yet? While skeptics point to that alone as evidence of non-existence, Meldrum thinks the animal is just very elusive. And just because it’s widely dispersed doesn’t mean it’s not rare. Finding Bigfoot, therefore, may be like finding a needle in a haystack.

Until someone captures a creature or finds the remains of one, all we have to go on are anecdotal evidence, some foot casts, and a bunch of out-of-focus pictures. But for enthusiasts like Meldrum, that’s enough to keep the faith alive.