Why Do Wolves Howl?
The common belief about wolf howling is that it is only done at night and when the moon is up. This behavior of all wolf species is actually a means of communication that is used in multiple circumstances. Howls are more common at night when the wolves are more active and in certain conditions they can be heard over a distance of 50 square miles.
Howling and Hunting
When hunting, wolves tend to howl to rally each other or right before leaving the den to bring food. Their howls can be heard over a great distance and in most cases, even their prey can hear them as they get close by.
Also, when multiple wolves howl together, they tend to harmonize instead of sounding like a chorus. This leaves the impression that there are more wolves in the group than there actually are.
Communication
Wolves use howling also as a means of communicating with each other. Females will often howl if there is an imminent danger at the den while the pack is out hunting. Pups also howl while playing or when they are alone.
Males use howling as a means to alert each other of their position or to communicate an incoming danger. Alpha wolves will often howl to attract females and communicate their willingness to mate.
Expressing Emotions
Wolves also express their emotional state when howling. A recent study showed that the members of the pack will mourn by howling when one of the wolves die. It can also be used to express fear when there is an imminent danger or to express aggression and so they can make their presence known.
When hunting, howling can serve as a means to express aggression and dominance. While chasing down prey, wolves will combine howling with short barks. When the chased animal decides to go into deep water, the wolves will wait on the sides, howling and intimidating the prey so that it will be afraid to come out of the water. This causes them to get exhausted and thus making them easier prey.
Common Misconceptions
Wolves do not howl at the moon, but they do tend to howl more often during the night when the wind settles down and less ambient noise is heard. Also, howling is never associated with physical pain. When wolves experience physical pain they use high-pitched whines.
Another common misconception is the fact that howling is always an act of aggression. Wolves use howling to also express sadness of fear.