The so-called "crackling" forest grasshopper refers to the loud sounds these insects make when disturbed. They fly up and away while flashing a very-visible yellow band on their hind wings and emitting a sound very much like that of a rattlesnake. It has been conjectured they have evolved this in mimicking the warning sound. Other entomologists claim the noises are for the benefit of the females, a sort of  "Hey, look at me" thing.  Either way, it's a startling, annoying habit, and these hoppers are extremely numerous at many locations in the Rocky Mountains.

I have seen these hoppers hover for as long as 30 seconds, and I have seen skipper butterflies drive off those so engaged, even though the hopper may be 2 or three times the size of the butterfly. I wonder why the Lepidoptera see the Orthoptrans as a threat?