Attacking at night may have been learned by watching wolves,bears,raccoons,oppossums,skunks.....almost anything realy.Using a bow at night may have been a plus because there eyes were already adapted to the dark before the attack, and was not ruined by muzzle flash.
Ill concur that they do tear up the coyotes,and i apreciate that.A pack of coyotes can do more dammage than one wolf.Ive caught 20 coyotes i a single back yard,in 10 days.They were over running the place.Nobody could own a dog because it got snatched off the porch as soon as they got it.Sometimes peoples dogs got snatched off the leash while the owners were walking them in the daytime! That month I caught 150 coyotes and quit keeping count.Its a big world out there,And animals act differantly where ever you go.