It's call and response, coyote-style. And it's one of the most intense examples of human-animal communication you've ever heard.
Coyotes are notoriously vocal animals. There's even research that suggests their howls can convey individually specific information. University of Vermont researcher Brian Mitchell hypothesizes that coyotes might use howls to identify which nearby coyotes they're familiar with. These howls, Mitchell notes, are different from barks:
Another interesting aspect of coyote barks and howls is that howls stably convey information for distances of at least one kilometer. Barks, on the other hand, rapidly attenuated and [do not] appear suitable for transmitting information. Barks likely serve other purposes, such as attracting information and providing information that listeners could use to estimate distance to the barking animal.
I wonder what information these coyotes think is being conveyed in this man's howl.
See also: Call and response, turkey style. Same concept, only 1500%* less-spooky:
*You know, roughly.