Were they a herd prancing majestically in the middle distance?
Perhaps.
Cornish writer Colin Wilson went into this phenomenon quite a bit in some of his books.
And for what it's worth, I have theorized on other similar websites that this could be the reason for many of the cryptid sightings. Please let me explain what my thinking is, if I may.
Sightings of cryptids tend, I notice, to be in clusters in a limited geographic area and usually a very definite time-frame. Several years ago, there were a series of sightings of Bigfoot/Sasquatch-like creatures near where I live, in northern Oklahoma. There was a few of them reported, and I suspect that many sightings were not reported, mostly for fear of ridicule. Among those who told what they saw was my cousin. A railroad crew saw something and there was another report from a town about fifteen miles away.
Then the sightings stopped as suddenly as they started.
About 150-200 miles to my north, there is the tiny farming town of Delphos, Kansas. In the early 1970's, there were a series of sightings of what became known as the 'Wolf-Woman'. There was a number of sightings all in a very small geographic area, with some very credible witnesses. Again, the sightings stopped as suddenly as they started.
A few weeks later, there were a number of sightings of a strange creature, this time in a small town in southern Illinois. The town's name escapes me at the moment. Once more, they ceased as suddenly as they started.
And if I am not mistaken the pterodactyl sightings along the Rio Grande separating Texas from Mexico, also occur in clusters.
Admittedly, this is speculation on my part, but could the reason that they occur in clusters like they do, be that they are caught in a time-slip? This could also be the reason that we have so little physical evidence of them. My speculation is that they are caught in a time-slip and then they are returned to their 'correct' time.
Speculation? I concede that it is. And while I am the one to advance this theory, it is not one that I am 'married' to, if you know my meaning.
So then, I ask what argues against this theory?