I have seen similar. We had been hunting deer in eastern Idaho near Afton Wyoming. Heading home the 19th of November going south on Hwy 89 somewhere north of Evanston and it was just breaking daylight when my cousin says look at that. There were bull elk for as far as I could see in the field just west of the roadway. Not a cow or calf anywhere. I videoed for about 10 minutes.
Absolutely amazing sight. Thanks for posting!