Wolves Communication Pack
COMMUNICATION AMONG WOLVES
Just like any other animal wolves communicate with each other, with most of its communication being between pack members. Wolves use three differing types of communication; 1) Vocalizations; Wolves are frequently heard at night because it is when they are most active. Wolves howl for many reasons, particularly to locate other members of the pack and to warn outside wolves to stay away from an occupied area. 2) Scent marking; Wolves possess a very keen sense of smell (about 100x's greater than humans). Wolves use this ability along with the others to communicate with other wolves. Scents are used to mark pack territories or lone wolf territories. These territories are marked most often by urination and defecation on or around trees and other objects. In addition to these two means of scent marking wolves also scent mark by scratching and scent rolling. And the last method of communication 3) Body postures; Wolves also use body language to communicate, whether it is to others in the pack or outside of the pack. Some postures are used to show affection, some fear or humiliation, others happiness and even others can emanate respect between pack members. All are important and used by wolves on a daily basis, whether it be to warn off competing packs, communicate a fresh kill or to portray dominance.
One of the things that distinguish different members of the family Canidae is the differential development of social behaviour. Among the close relatives of the domestic dog, the most highly social species is the wolf. Wolves belong to a family group often referred to as a pack. This social structure was originally thought to allow the wolf, a social predator, to take prey many times its size, however new theories are emerging suggesting that the pack strategy instead maximizes reproductive success and has less to do with hunting. They live, travel and hunt in these packs which consists of anywhere from four to fifteen members (pack sizes are subject to change overtime and are controlled by such things as food supply, individual personalities and habitat type). The rare exception is the lone wolf, this wolf will most likely be the omega wolf, the lowest ranked member of the pack, and if it is lucky will find a mate and start a new pack. Wolf packs have a very elaborate hierarchy, one in which is topped by the alpha male and female, followed by their pups, often several sub-adults from the previous year's litter and sometimes some older siblings as well. When pack sizes are large (usually more then 8 members) it is possible to witness two differing hierarchies in one pack, one in which is the females being led by the alpha female and the other the males being led by the alpha male. The alpha pair share the most social freedom among all pack members, they are very influential and simply have the most freedom in where to go, what to do and when to do it, with the rest of the pack usually following. The alpha male and female therefore usually direct the pack in hunting and tracking prey, choosing den sites and establishing and maintaining the pack's territory. Rank order is ascertained and sustained through a series of ritualized fights and posturing best expressed as ritual bluffing. Wolves prefer physiological warfare to physical confrontations, meaning that the higher ranking status is based more on personality or attitude rather than on size or physical strength. Rank order may be lost rather suddenly or gradually. An older wolf may simply choose to give way to a motivated challenger, yielding its position without bloodshed. On the other hand the challenged individual may opt to fight back with varying degrees of passion.
Wolves communicate using three main strategies; 1) vocalizations- howls and growls; 2) facial expressions and body postures and; 3) scent marking. Howling alone can have a variety of meanings; a greeting, a rallying call to gather the pack to get ready for a hunt, an advertisement of their presence to warn other wolves away from their territory or spontaneous expression of play and bonding. The howl of a wolf can be heard up to six miles away making it the most useful means of communication given that wolves range over large distances while hunting and traveling. Wolves engage in a variety of displays of dominance, and submission that helps reinforce the hierarchy in packs. Wolves use their entire bodies; expressions of the eyes and mouth, the position of the ears, tail, head and overall position of the body are used to convey excitement, anxiety, aggression or compliance. Wolves also wrestle, rub cheeks and noses and nip and lick one another. They leave behind messages for themselves as well as other pack members by means of urination, defecating or scratching the ground to leave scent marks. These marks can set the boundaries of territories, record trails, warn off other wolves or help lone wolves find unoccupied territories. In a similar fashion wolves will roll around in items with a strong scent such as carrion as a way of letting other pack members know where they have been or what it has encountered. In the end it can be said that the “habits of the wolves require members of a social unit to be visually separated at times so that these olfactory and auditory means of communication are possible” (Berge, 1967).
“The wolf is a wide ranging social carnivore with a complex spatial organization for which acoustic communication plays an important role” (Palacios et al. 2006). There are four kinds of vocalizations that are popular among wolves, they include; the growl, the whimper, the bark and the more associated sound of the wolf, the howl. Any one of these or a combination of these allows the wolves to communicate with one another. The bark can be used over long distances and can take on the roll of sounding an alarm or presenting a challenge. The alarm bark is most often used when a wolf is caught off guard and surprised at the opening of its den, and a challenge bark is a warning for a wolf to back off when two wolves are encountering a “face off” (a fight). The growl has similar meanings to the bark however it is used in shorter distance communication. It is used to keep other wolves away, to reinforce dominance and, it can also be used at short range to challenge. The whimper is used at short ranges as well and portrays a sociable stance (often used by young to receive care). The howl, the most well known form of communication among wolves, seems to have many complex functions and will be looked at in greater detail compared to the other three types of communication listed above.
Howls allow wolves to communicate over several kilometers. Howls have been described as long harmonic sounds with a fundamental frequency from 150Hz- 1000Hz for adults. There have been two types of vocalizations involving howls that have been recorded; 1) Solo howls and 2) Chorus howls. Solo howls, also referred to as a lonesome howl is emitted by a sole individual. In the study down by Berge many years ago unique features were found to exist in individual howls. Harmonic characteristics were found that would distinguish individuals on the basis of any one howl. Therefore the variation in structure likely indicates who is howling and the frequency modulations, predominantly the change in pitch makes the howls much easier to locate. The ability of a wolf to detect these very subtle changes in sounds indicates that a response to this information is possible (view figure 3). As with any form of behaviour there is a cost/benefit to this action. The lone wolf is just that, it is alone, and when producing sound its pack mates are not the only ones who pick up the vocalization, thus this behaviour could turn out to be detrimental. However with any cost comes with it benefits, a lone wolf's howl can help one locate the other members of its pack proving to be advantageous. A chorus howl on the other hand has been described as a vocalization in which one wolf begins howling, with the other members joining in subsequently until the whole pack is howling together. Rather than using howls with a single pure tone, wolves use modulated tones. With the rapid changes in pitch it makes it very difficult to follow only one individuals' howl, and to add to it the surrounding environment helps reflect the sound and scatter it making it extremely challenging for a competitor pack to distinguish where the pack is and how many members the pack consists of.
The heart of a wolfs' universe is its pack and howling could be the adhesive that keeps it together, suggesting that howling may reinforce the social bonds between pack members as well as keeping the pack safe. In view of the fact that wolves are separated great distances during a hunt, it is not unlikely that howling keeps the pack as one physically. Of all their calls howling is the only one that works immensely over great distances. Its long duration and low pitch are what make it suitable for long range communication through the forest and in tundra areas. Its unique features are what allow a wolf to convey its identity and each wolf can be identified by its pack just by means of its howl.
While howling may provide much information about a wolf's whereabouts elaborate spatial patterns of scent marks provide precise information about inhabited territory. A territory is a “space within which an animal is aggressive to and usually dominate over certain intruders” (White et al, 1996). It is a silent way of steering clear of violence that would otherwise be required to preserve a territory. Scent marking can also provide a silent exchange between animals that share territories and can also help an individual keep its point of reference when traveling. When Roger Peters and David Mech conducted studies on a variety of wolf packs in the Superior National Forest of northern Minnesota they found that wolves scent mark using four differing methods. The first method is by means of raised leg urination. “This form of scent marking is closely connected with territorial marking and maintenance” (Macdonald et al. 1998). These markings are made throughout the territory and heighten in concentration at the limits of the territories. The alpha male and alpha female are the primary users of raised leg urination (more often it is the alpha male) with only few instances where it will be used by other wolves. The second mode of marking is squat urination. This mode of urination is the ordinary form of urinating, and is performed by the lower ranking individuals in the pack. This method of scent marking supplies them with information about which fraction of the territory has been hunted during times of separation. Scratching, and or scent rolling the third strategy to scent marking involves a wolf that may rub its lips and neck against a tree or on the ground or scrape the ground with their paws (normally after urination) to mark out their territory. Scraping, usually with the hind legs and sometimes also done with the front is predominantly performed by the dominant individuals, the alphas (can be done by mid ranking individuals depending on the circumstances). Wolves have scent glands between their toes which release odours/ a characteristic scent. The wolf has several specialized glands, located all over the wolf's body that function as a chemical and a visual message for other wolves. There is one located near it anus (anal gland), another on its back, one at the tip of its tail (precaudal gland), in its eyes, behind its ears, on its cheek near the corner of the wolves mouth and between their toes (as mentioned above). The aroma from these glands is as individualistic as our own fingerprints. Each scent is specific to an individual each with its own meaning. Scats also referred to as defecation is then the fourth means of marking. Again this form of marking is very similar to that of urination and serves many of the same purposes. However here it acts as a more visual warning. Here again the anal scent gland becomes important. It produces a pungent oily pheromone that is excreted during bowel movements, thus scenting the wolf's scat with his/her own odour. The exact purpose of this means of scenting is unknown however it could very well be that these anal scent glands play an imperative role in wolves of higher ranking for it has been observed that when higher ranking individuals meet they sniff under the tail, this action is not performed by submissive wolves (lower ranking wolves). (Refer to figure 1 and table 1)
“Olfactory communication is defined as the process whereby a chemical signal is generated by a presumptive sender and transmitted to a presumptive receiver who by means of adequate receptors can identify, integrate and respond to the signal” ( Kleiman, 1972). Scent plays a exceedingly imperative role in the life of a wolf, by smell alone wolves can locate prey, other pack members or enemies. It can tell them if other wolves were in their territory, if they were male or female and how recently they were there. Therefore marking can be used for non-territorial purposes as well. It can also be used to identify individuals, lay claims to a kill, for navigational purposes during those long ranging hunts and can also be used as a indication for sexual receptivity during mating season ( suggested that this is the purpose of sniffing under the tail upon greeting).
Wolves convey their emotions through body language. Here they can “communicate visually a number of expressions and moods that range from subtler signals to more obvious ones” (Berg, 2003). The following are observed behaviours. Wolves display dominance by standing tall and stiffed leg. The ears are erect and forward and the tail is held vertically and curled toward its back. This demonstration declares the wolf's rank to the rest of the pack. Submission can take the form of either active submission or passive submission depending on the circumstances. In active submission the wolf lowers its entire body toward the ground and the lips and ears are drawn back, in essence the teeth are bared. The tail is down and either half way or completely between its legs (depends on level of submission) with their muzzle (refer to figure 2) pointing up toward the more dominant individual. The back will be arched and again depending on the level of submission the back may be arched more or less. During passive submission, a more intense form compared to active submission the wolf will roll over onto its back and render its susceptible throat and underside, with the paws being drawn into the body. If a wolf is displaying anger its' ears will be erect and its fur may bristle. Here the teeth are bared and it is usually accompanied by a snarl or growl. When a wolf is fearful it tends to make itself look small and less conspicuous. The ears flatten and again the tail is tucked between the legs. If a wolf senses danger suspicion will arise. This is displayed by the pulling back of the ears and the narrowing of the eyes. The tail will be parallel to the ground and pointing straight out. A playful wolf will hold its tail high and wag it. The wolf may frolic and dance around, or bow by placing the front of its body down to the ground all the while holding its rear in the air. (Table 2 summarizes body postures)
Wolves are multifaceted social animals whereby communication signals are used for a variety of purposes. In order to function as a group communication among individuals in a pack is crucial. Communication is used for recognition, reproduction, social status, alarm, foraging and group spacing also referred to as territoriality. “The wolf is a wide ranging social carnivore with a complex spatial organization for which acoustic communication plays an important role” (Palacios et al. 2006). There are four kinds of vocalizations that are popular among wolves, they include; the growl, the whimper, the bark and the more associated sound of the wolf, the howl. Any one of these or a combination of these allows the wolves to communicate with one another. While howling may provide much information about a wolfs' whereabouts elaborate spatial patterns of scent marks provide precise information about inhabited territory. Scent plays a very important role in the life of a wolf, by smell alone wolves can locate prey, other pack members or enemies. It can tell them if other wolves were in their territory, if they were male or female and how recently they were there. Therefore marking can be used for non-territorial purposes as well. It can also be used to identify individuals, lay claims to a kill, for navigational purposes during those long ranging hunts and can also be used as an indication for sexual receptivity during mating season. Wolves communicate at close range their emotions through body posture, tail positions and facial expressions. Here they can “communicate visually a number of expressions and moods that range from subtler signals to more obvious ones” (Berg, 2003). All forms of communication are important and used by wolves on a daily basis to ensure that they stay in touch with the rest of the pack.