On one hand, apparently drones seem to seriously fuck with wildlife that they observe. http://news.nationalgeographic.com/2015/08/150825-drones-animals-w ildlife-bears-science-technology/ (I've seen reports that wildlife other than bears react similarly.)
On the other hand, it's literally a rattlesnake pit.
It doesn't say it's a drone in the video description, it doesn't make any noise in the approach, and it moves through the scrub which would crash anything small enough to get in that wash.
Really, it's "Snake yanks gopro off selfie stick".