Right so I've been down this rabbit hole for a few weeks now after someone posted a map of US dogman reports and I started cross-referencing with old railway routes. The overlap is genuinely unsettling, way more than I'd expect from coincidence alone.
My thinking is it's probably about the corridors themselves - old rail lines cut through isolated terrain that hasn't been developed, so you've got these long strips of undisturbed land connecting remote areas. If something large wanted to move between regions without being spotted, that's exactly the route it would take.
What I can't figure out is whether the sightings cluster near active lines or specifically abandoned ones. Does anyone have data on that? Because that distinction matters quite a bit for any theory about what's actually driving this pattern. I've found a few cases near disused lines in the midwest but my sample size is too small to say anything definitive.
Also curious if anyone in the UK has looked at this in relation to old canal towpaths or drove roads, we've got our own unexplained creature reports and nobody seems to map them properly.