What’s in the Wolves’ Howl?

Ask anyone about vocalizations of the wolf, and it always comes to mind that "howl". While wolves bark, woof, whine, whimper, yelp, growl, snarl, and moan much more frequently than they cry, the wolf is defined by howling, and fascinates us. So why the wolves are howling?

His pack is the core of the universe of a wolf, and howling is the glue that keeps the pack together. Some have suggested that howling strengthens pack mates ' social bond; the pack that howls together remains together. That may be so, but with nasty quarrels between pack mates, chorus howls can also end. Some members may effectively be "punished" for entering the chorus, generally the lowest rank. It is unknown whether howling together actually strengthens or merely reaffirms social bonds.

However, we do understand howling physically keeps pack mates together. Because wolves are able to locate food in vast fields, they are often segregated from each other. Howling is the only one of all their calls that operates over excellent distances. Its low pitch and long length are well suited for forest and tundra transmission, and the distinctive characteristics of the bark of each individual enable wolves to distinguish each other. Howling is a long-distance call to contact and reunion; separate a wolf from his pack, and shortly it will start howling, howling and howling...

THE “LONESOME” HOWL

You can classify the sequence of other adult howls that is heard as "lonesome" or "lone" howls.  The variation in their composition probably shows who is howling, and the frequency modulations make it much simpler to find the howls, especially the sudden pitch changes.  These other wolves may be members of neighboring hostile packs which are territorial and prey rivals. Howl too close to these strangers, and they may be looking for you, chasing you, and killing you. In northern Minnesota, where wolves are protected from humans, the primary cause of death for adult wolves is being killed by wolves from other packs. So howling has its costs (running into the opposition) and benefits (returning to the pack). Wolves are therefore careful about where and when they howl, and to whom they howl. For instance, a wolf separated from his pack may return and hurl for hours to an abandoned summer rendezvous site, even in reaction to a neighboring stranger. At that site, wolves are used to howl and likely feels comparatively comfortable and safe there. But the same wolf is going to be much more reserved away from the old home site, and if a stranger howl nearby, it can retreat quietly and rapidly. Pups, especially those under the age of four months, love to hurl and usually respond to whatever hurls they hear, even the total strangers. This is understandable, as pups have yet to learn how to define their older pack mates.  

THE “PUP” HOWL

Indiscriminate howling is generally not a hazardous proposal for young pups, as they tend to be stuck at a rendezvous site comparatively far from neighbors, who probably have their own pups to raise. More importantly, responding to an adult who often howls leads to a meal, as pack mates often hurl with food as they come close to home. But as summer breaks down, the advantages of indiscriminate howling are diminishing.

When pups start traveling with the pack, they start entering less safe surroundings. Their neighbors travel more as well. Remote howls may belong to strangers, which increases the hazards of howling. In addition, by now they have had plenty of time to learn their own pack mates ' voices and are prepared to discriminate against the foe's friend. Pups have become as selective as adult wolves by six months of age about where, when and to whom they howl.

There's one pack member who's going to howl more courageously: the alpha male. The alpha male is the pack's dominant male and the pups ' dad. He's most probable to hurl a stranger — often with conflict on his mind— and even approach him. One sign of this aggression can be heard in his voice; as he approaches a stranger, his howls become lower-pitched and coarser in tone. Reducing a vocalization's pitch is an almost universal indication of growing mammalian aggressiveness, and it may sound quite impressive in wolves.

THE “CONFRONTATIONAL” HOWL

This conduct points to the second primary purpose of howling: to help keep the rival packs apart. When one pack howls, there may be others nearby to answer.  All the wolves understand the place of each other very rapidly. Packs can keep their neighbors at bay by advertising their presence and prevent running into them accidentally.

But it is difficult to use howling in spacing. If one pack hurls, its position is now known to all its neighbors (within range of course). What if they decide to remain silent, pick up and attack the howlers? Deliberate attacks were seen from one pack to another, so advertising costs for your location are incurred. These hazards must be balanced with advantages. An instance of this trade-off is sometimes seen in winter, when packs travel nomadically within their regions (or even outside them). A pack sitting on a newly killed prey, especially if a stranger howl nearby, is likely to stake his claim and howl. The wolves become less invested in the site as time passes and the kill is eaten and are less likely to respond. They may eventually react to the howling of a stranger by quietly moving away.

When two packs meet, the result is generally determined by their relative size. Small packs are therefore often quite hesitant to hurl and attract attention to themselves, whereas big packs are quick to howl.  But about their size, packs can fib with each other.

They frequently participate in behaviors intended to exaggerate their size when animals compete. Wolves stand tall, lift their hackles, ears and tails, and generate low, threatening howls, all to persuade their adversary that the best choice is to withdraw from this "big, bad wolves." Most confrontations therefore require a great deal of bluff and very little bloodshed. Similarly, it is more probable that packs that can exaggerate their figures will maintain their neighbors at bay. This kind of deception is well adapted to the structure of a pack or chorus chant.

A “CHORUS” HOWL

Wolves howling in a chorus use wavering or modulated howls instead of using howls with a single pure tone. The fast pitch changes make it hard to follow the howls of one individual when several others are hurling at the same time. Moreover, as the sound moves through the setting, it reflects and disperses trees, ridges, rock cliffs and valleys. Competitive packs therefore hear a very complicated combination of direct sound and echoes. If the howls are quickly enough modulated, two wolves might sound like four or more. He reached the couple of wolves a short time later that made all the noise! This phenomenon, called the Beau Geste Effect, may create sufficient uncertainty to render estimates of size not only unreliable, but possibly deadly, if a pack underestimates the size of its competitor and approach.

So wolves are howling to discover their friends and maintain their neighbors at bay. Popular imagination has long kept them to howl at the moon as well, but there is no proof that this is so. Wolves may be more active on moonlit occasions when they see better, or we may hear them more frequently on such occasions because we feel more comfortable trampling in the light of a full moon, but a wolf howling on the moon would be wasting his breath.

Source: The Mystery of Dark Wolves

https://www.youtube.com/watch?v=odbzQBS0smQ