The Wolf - Ecology and Behavior of an Endangered Species Summary Notes PDF

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Dr. Tricas...

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Prey on more easily attainable prey → deer over moose (8) Adapt to moose when only available Learned to head toward gunshots (8) Moose gentle, likely due to pack social dynamics Good memory (8) Shy / Skittish (9) After wolf pups reach a certain age, they do not befriend other wolves (9) Emotional bonds to wolves in their pack but not other packs Extreme fear → 4 stages - escape, avoidance, approach, and socialization Only occurs in lab setting, would not occur in wilderness Could spend 20 minutes chasing prey (14) So exhausted after hunting it won’t move for hours

Strong smell unless prey is downwind Good hearing Rely on smell and hearing, but should have good vision for movement Large range of fur color, but grey predominates → other colors increase with latitude Older wolves are greyer → denser fur in northern latitudes Disagreement on how often they molt → one said once in summer and twice, once in april and once in august Canis rufus (red wolf) is a separate species

Wolf confused with coyote → closely related 3 geographic subspecies of redwolf (C. rufus) → extirpation (local extinction) of red wolves due to 1. Non-adaptability of red wolves to changing environmental conditions including competition with coyote populations 2. Probably hybridization between red wolves and coyotes 3. Range overlaps with wolf and coyote 4. In overlapped areas, it resembles the species it overlaps with Red wolf is a rac of grey wolf

Many races of grey wolf based on characteristics and skull measurements Possible coyote-wolf hybridization, meaning they are the same species Breed once a year Various races of Canis familiaris from a single wild species C. lupus Dog is similar to wolf and should be a form of wolf, not a separate species Originally inhabited northern hemisphere, now it has wide distribution, vayring by area Geographic races are considered the subspecies Traits to distinguish wolves by areas → color, gross average size, general form and size of skull, height of braincase, frontal profile, rostrum length, and size of auditory bullae 2 major groups → timber and tundra wolves Timber → forest areas and grey to black; pointed ears Tundra → mostly light, but some are black; rounds ears Population of wolves that differ substantially from population of areas as subspecies Hard to distinguish subspecies → what is enough of a difference 32 subspecies recognized globally with 24 in NA and 8 in Eurasia No boundaries besides geographic → ex. Islands All N hemisphere habitats besides tropical rain forests and arid deserts Can survive in arctic tundra, savannahs, plains, taiga, mixed forests → all originally inhabited by wolves No other wild land mammals has a greater geographic range More restricted range now → north america and western europe Ecological niche → northern predator upon large mammals Most predation of large mammals in N hemisphere due to wolf

Packs: ● Group hunters ● Pack → group of individuals that travel, hunt, feed, and rest together ● Wolves are rarely seen alone ● Most groups are 7 individuals or less, but could be up to the early 20s ● Pack size typically relates to wolf densities

4 possible factors on pack size: 1. Smallest # of wolves needed to locate and kill prey 2. Largest # that can feed on prey 3. # of other pack members with whom they can form social bonds (social-attachment factor) 4. Amount of social competition that members can accept (social competition factor) Larger packs = higher competition for food, maters, dominance, etc. Social-competition is limiting factor Little known on pack formation or origin of pack members Average of 6 young per litter Sexually mature at 22 months Strong bonds hold group together

Pack - Social Interactions: 3 Common types of relationship: ● Courtship and mating ● Raising of litter by adults ● Growing and developing of young in company of littermates Must overcome fear before accepting a strange wolf or human Pups less than 12 weeks easily establish friendly relations Adults require 6 months of training, while pups less than 8 weeks make positive responses upon first contact 8-10 weeks → pups leave the den and meet strange wolves At 7 months → difficult to form new psychological ties without forced training and experimental conditions Choose mates around a year old, but do not mate for an additional year Long period of heat Copulatory tie → unknown, but could help social bonding Pups are fed not only by parents, but by other adult members of the pack Packs are groups of related individuals Basic element of wolf pack is breeding pair → at least one mature male and female or pups present in all packs

Largest packs seen in winter, while summer shows smaller groups and lone wolves Pack formation in early winter 3 Reasons larger packs occur in winter: 1. Conditions for observation are best during that season 2. Pups are afield with the rest of the pack 3. The pack wanders a lot together, so the social center, where most members gather, is not the den (like it is during the summer), but rather the traveling pack itself

Birth of excess males → disproportionate sex ratios

Pups composed an average of 43-48% of the total annual population Low survival of pups from birth to age of 5-10 months (survival rates from literature indicate 6-43%) Adults averaged 6.5 pups and yearlings with 5.4 pups Once a wolf survives its second winter, each year it has an 80% chance of survival, assuming no human exploitation Protection of mating pair in zoos

Human exploitation → snaring, poisoning, or hunting Natural survival rates of 20-88% for pups from birth to period of exploitation Survival rate depends on degree of exploitation Ontario data suggests a 100% survival up to 22 months sand 36% thereafter Discrepancy between Alaska and Ontario may be due to small sample size in Ontario Annual mortality under natural control → 5-10 months is 13-31% Annual mortality under heavy exploitation → 50%, but could be between 35-73%

Regulation of wolf numbers occurs with or without human activities such as hunting or trapping causes of mortality

Even though wolves were legally protected, the numbers were not increasing

Social Order, Expression, and Communication: 2 factors for groups to function efficiently: 1. System of order 2. System of communication that promotes that order

“Peck order” → a social “ladder” where each member of a group occupies a rank or position seen in domestic chickens In this case, known as a “dominance order” 2 dominance orders per pack: 1. Male order 2. Female order Highest-ranking male is “alpha male” and top female is “alpha female” Original alpha is the mated pair that produced the young of which the pack is composed Alpha male may refrain from breeding at some point and a lower-ranking male may mate with the alpha female, but the alpha male is still dominant 3 other classes of wolves: 1. Mature subordinates 2. “Outcasts” or “peripheral” wolves → so low they avoid the main pack members and stay at fringes of pack’s social center 3. Juveniles → not part of pack until second year of age Pecking order determined by “play fighting” by littermates → can be as early as 30th day of life When an alpha male dies, the competition for alpha male disrupts social stability of the pack The pack could breakup when the alpha male dies and could be important in formation of a new pack 2 aspects of dominance: ● Privilege and leadership

“Ownership zone” within 1 foot of a wolf’s mouth

Once a wolf possesses a piece of meat, it is his beyond dispute, but more work is needed

Leadership: ● The behavior of one wolf that obviously controls, governs, or directs the behavior of several others ● Excluding situations where a pack may be filing along a regularly used trail ● Determines the hunting route, when to stop the chase, when to rest, etc. ● Leader is most highly motivated ● An alpha male is only dominated by a female when she is caring for newborn young ● Guarding function of the leader ● Autocracy → they follow no matter what ● Democracy → leader notices behavior of pack members ● Or both ● Leader acts independently for direction, but slightly influenced by pack behavior Pack Interactions: ● Order rules ● Behavior of members directed at keeping or raising their own status ● Drastic disturbances in living conditions can trigger a status rearrangement ● Social changes, such as loss or addition to pack, has the greatest effect When alpha male was taken out of pack, beta male took over and remained new alpha male even when original alpha male returned to the pack. The original alpha male become the lowest-ranking male in following breeding seasons To preserve status, a wolf has to constantly assert its position

“Energy-displacement” activity → picking on lowest pack member Dominant members often ambush or attack subordinates to assert dominance

Possible that touching mouths indicate that they are hungry → like pups up to 5 months asking for regurgitated food Main feature of active submission if friendliness and tolerance → especially in “wolf greeting” Subordinate nips, licks, and smells mouth of dominant wolf

Passive submission is more extreme than active submission → characterized by timidity and helplessness

Communication through odor: ● Olfactory sense ● Difficult to study ● Involved head and neck or anal-genital region ● Head and neck is friendly ● Scent marking → wolf leaves odor on an object and other wolves investigate it

Vocal Communication: ● Wolf sounds → whimper, growl, bark, and howl and “social squeak” ● Whimpering is a submissive or friendly greeting sound (usually in pups) ● Growling conveys aggressiveness ● Barking is call of a chase, while others believed it to indicate excitement or alarm ● 2 kinds of barking → an alarm or as a threat/challenge to intruders ● “Refractory period” after howling ● Seasonal differences in response to howling → 3x higher responses in July and August than My and June → females with pups rarely respond during early pup development; may be to keep den location secret from other predators ● Pups began to reply in later summer ● No atmospheric or environmental effects on howling → wind affects howling (100) → response 10x greater during calm periods than windy weather ● Function of howling not known ● Emotional state probably the stimulus for howling ● Howling helps to assemble the pack ● Ability to identify a wolf by its howl ● Fine auditory discrimination

Territoriality: ● Territory - “defined as the area that the animal will defend against individuals of the same species” ● Intolerance → undocumented between two packs ● Wolves unfriendly/hostile to wolves outside of their own pack

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Aggression is defense of a range or territory → territories include hunting and traveling areas Definite home ranges overlap somewhat

Communication Among Packs: ● Typical territory is 100 square miles or more ● Scent marking → urination, defecation, or rubbing body parts on an object ● Objects marked by urine → “scent posts” or “scent stations” → can be any object ● Many wolves in a pack may wait to urinate on same object and every time they pass it, leading to frozen urine ● Urine of a strange wolf gets pack excited ● Disagreement on subject, some thinks it is territory advertisement as they can tell their own scent ● Can tell how old a scent post is ● Dogs scent mark a station after another dog does ● Scent marking in dogs contributes to territorial spacing and thought to have similar function in wolves, but more evidence is needed

Vocal Communication - Hearing: ● Humans can hear wolves howling up to 4 miles away and wolves can probably hear better ● Howling can advertise the pack presence over 50 square miles ● Wolves reply to howls of adjacent packs ● Howling → advertisement and defense of a territory ● Wolves do not seek out neighbors howling and chase them ● Alarm bark when too close → threatening bark

Reproduction and Family Life: ● Not all wolves bear pups, they help to take care and feed them ● Advantages of group care of young ● Mating urge until 22 months ● Matings can occur between littermates or between parent and offspring

Courtship Behavior: ● Males generally initiate 3x the number of courtship actions as females, but that depends on the individual Dominance order in relation to mating: ● Alpha male and female are only ones that mate ● Alpha male does not mate much 1. 2. 3. 4. 5.

Dominance rivalries increase before breeding, especially in females Alpha male is preferred by most females Dominant males disrupt courtship mating attempts by subordinate males Alpha female prevents other females from mating A dominant animal will often interfere with mating attempts by individuals of the opposite sex 6. A subordinate male can thwart a superior’s courtship a a mutually preferred female by moving between the 2 7. The mate preferences are related to dominance order when pups mature

Average litter contains 4-6.5 young Gestation period is 62-63 days

Denning: ● Complete digging of dens as early as 3 weeks before birth of pups Birth, Growth, and Development of Pups: 1. Period of maximum growth 2. Period of rapid growth 3. Period of slow growth Information difficult to collect

4 Developmental Periods: 1. Neonatal 2. Transition 3. Socialization 4. Juvenile

Wolves may settle social status early in life Development of social-behavior patterns during period of socialization - and formation of emotional bonds Only individuals nearby pups are littermates and adults in pack, so emotional attachment are formed in these animals

Human-Wolf Attachments: ● Mutual extension of friendliness ● Reception of reward ● Relieving emotional distress by rejoining individuals whose isolation from each other causes distress Begging behavior provides postural and psychological basis for active submission Maybe connection between loneliness and howling

Wolves do not have inborn tendency to kill → born with certain behavior patterns that allow it to learn to kill By 3 months, it takes significant effort to make pups form new social attachments If pup meets alien wolf with emotional attachment, unity of pack breaks and entire organization does too...