Wolf sympathy for certain kind of fruits is frequently anecdotal.

Wolves are obligate carnivores, so we fill their watermelons with treats they do like. Either way, the watermelon is enriching because it provides the wolves an opportunity to utilize their instinctive behaviors. [..] This behavior is known as dissection and we give our wolves the opportunity for this behavior with feeding carcasses, enrichment boxes, and other sources such as watermelons.

— Wolf Park interns staff once explained the point via instagram.

Voyageurs Wolf Project again delivered evidences about another rare behavior, discovering not only Minnesota gray wolf individuals eating berries purposefully, but also regurgitating them to their pups (rendezvous point, nearby a den).

It left me with some questions. - How important food are forest fruits for wolves? Is it a local population's adaptation to conditions offered by an ecological niche? Or maybe evolutionary adapted biological changes, distinguished for modern gray wolf species? - Regurgitated berries' leftovers, found by researchers afterwards, weren't completely digested (and completely eaten), they were partially chewed.

According to respectable scientific sources, the gray wolf remains a typical predatory animal with complete predatory sequence being used in hunt, where its diet was defined as obligate carnivore - like feline, including domestic cats - they need their diet being strictly based on meat, without the physical ability to digest herbivore-oriented nourishment. However, VWP discovery could possibly point on the facultative carnivore - canine like domestic dog - option, if the answer to WHY wolves eat fruits, would be scientifically clear.

Sticking to Coppinger's theory, primal dog (self)domestication process caused pre-dogs to give up their predation and hunting habits for scavenging, making them become the first predatory species put through the human-focused domestication process.

It is however not clear whether this change was associated with the initial domestication, or represents a secondary shift related to the subsequent development of agriculture.

—  study reports, researching DNA samples of 392 dogs (incl. 95 regional types, 19 native Greenland ones, 25 Australian Dingoes and 126 multiple breeds allover the world) in comparison to selected wild canids (5 golden jackals, 1 coyote, 51 wolves in wildlife and 15 sanctuary ones).

Other scientists previously confirmed the adaptation to starch-rich food based diet itself, comparing the dog genome to the wolf one in detail, where differences (36 genetic regions) were categorised, inter alia, into

• genes (19) responsible for behavior traits (brain functions, nervous system development pathways)
• genes (10) responsible for starch digestion and metabolism of carbohydrates

and 3 additional dog genes (AMY2B, MGAM, SGLT1) exclusively, which appeared responsible for glucose reuptake.
So, habitat established by humans who changed their way of life from nomadic (hunter-gatherer) into settled (agriculture, then animal husbandry), made dogs evolve to be more omnivore than carnivore.^[1]  Their digestive system (gastrointestinal tract, intestines) is currently longer and more weighty than it is in case of wolf - pack hunting, demanding them to consume instantly.

Obviously, hard to imagine any forest animal's diet containing a vegetable or strachy fruit, planted by human in principle. Anyway, feasting wolves eagerly start consuming a preyed animal's carcass from its internal organs regularly containing the rest of half-digested plants (herbivore-oriented diet).^[2]

Organ meat is the first to be eaten. Except in rare cases, all significant pieces of muscles are eaten. Ribs are typically eaten, bones are often partially consumed, and nearly all the hide is commonly eaten. Even the muscles that make up the lining of the stomach are eaten.^[3]

Wolf natural diet consists approximately 90% meat (protein), sometimes switching to fruits like documented berries, which deliver a bit of minor portions of carbs (likely just a water).

To survive (consume, avoid a danger, reproduce) does not mean to thrive (health, animal welfare, strong/attractive partnership/company). Modern dogs (free-ranging scavengers or companion animals) are able to thrive on a diet rich in plants, whereas wolves (typical apex predatory) hypothetically can survive on it, but they obligatory require a high-meat diet to thrive.
Even if gray wolf and domestic dog both split up from a common ancient wolf ancestor.

References:
Diet adaptation in dog reflects spread of prehistoric agriculture (2016); study by group work
The genomic signature of dog domestication reveals adaptation to a starch-rich diet (2013); study by group work
Coppinger Raymond, Lorna; „Dogs. A Startling New Understanding of Canine Origin, Behavior, and Evolution” (2002), "What is a dog?" (2015), "How Dogs Work" (2016)

^[1] Being precise, domestic dog adapted its digestive system to absorb proteins (amino acids) coming from legumes. The rest is evolutionary adaptable absorption of carbohydrates - from grain plants, starchy root vegetables and starchy fruit - in digestible form (energy value).
^[2] Hard starch (vide hay or straw) is not digestible to whichever mammal, but supports omnivorous digestion process as an indigestible fiber (cellulose), then being excreted (final section stage).
^[3] citation after Moose & Wolves if Isle Royale project

"Fetch it!" - or even more official "Fetch!" if used in dog obedience training (fetching on command) - is a verbal signal causing a positively reinforced dog to retrieve an indicated item directly to the handler (ultimately to the handler's hands).

Retrieval itself stands for a grabbed 'prey' being dropped intentionally nearby (at the human’s feet, handing it to a human, etc.) by a dog which returned with it to the handler. To fetch means to trigger a specific behavior chain (partial predatory sequenced) associated with a toy tendency (play behavior preference, prey drive correlated) as a part of dog-human relations (social behavior element, an indicator of how much a dog is predisposed to cooperate with a human).

Some young dogs have a natural fetch - they play fetch as puppies and retrieve a fetched toy to a human instinctively. Anyway, dog cubs do not come into the world naturally born tame, but just evolutionary open to the domestication process. They habituate to human presence during a very short developmental stage related to the optimal socialization window - the most sensitive part of the dog offspring management. Likewise, properly handled captive born wolf cubs (less tamable than dog puppies, with way much shorter socialization related part) are temporarily taken away from their wolf parents (extremely early) and hand-reared by professional caretakers (feeding them every 3 hours, sleeping together) to habituate to human presence by imprinting (assuming not all senses activated yet) optionally even before their socialization window is open.

Christina Hansen Wheat researched 13 wolf pups of 3 litters in the lab placed 100 km away from the patronage institution, putting them being 7-9 weeks old through standard behavioral tests usually used by dog breeders to assess predispositions of working dogs (then matching every puppy to an appropriate owner). A stranger - who every tested animal was left with in a barren room - was supposed to throw a tennis ball and urge each wolf pup separately to bring it back.

Let's consider the video material in the context of genus Canis predatory sequence and complex social behavior focused on human:

• Prey drive is triggered by moving/flying object thrown by a handler like it happens in nature - the ball is chased then grabbed in regular way preceding the 'killing' link.
• The "killed prey" is taken away to 'dissect' - redirected into independent play behavior elements (putting the toy into motion, dummy chasing simulation).
• The handler is trying to redirect the cub's attention like it proceeds in dog frisbee where a trained dog is encouraged to retrieve a flying disc after catching it (which closes canine predatory sequence when the 'grabbing' link is reached).
• Tested wolf pup is fetching the ball, seemingly intending to retrieve it to the handler.

The test results does scientifically matter - 3 of 13 tested wolf cubs spontaneously passed showing interest / not ignoring the ball being thrown (all of the same litter); 2 of them (Lemmy and Elvis) returned it twice, 3rd one (Sting) did it every time (3 trials scheduled).

Our results suggest that, although probably rare, standing variation in the
expression of human-directed behavior, including play, in ancestral populations could have been an important target for early selective pressures exerted during dog domestication.

— researchers report.

Both genus Canis species have a common wolf ancestor from which they split up around 15,000 years ago, into two (sub)species.

• Pre-dogs abandoned wildlife for being a companion animal - cooperative, human focused, depending on human as a resources management (preliminarily adapted to scavenge).
• Wolves remained wild predators, strictly carnivore social animals living/hunting in packs deep in forests, avoiding humans as much as possible.

There's a possibility that modern wolf populations diverged from the primal one which put pre-dogs into domestication process previously. Extensively hunted in the past, their descendants might be more vigilant and avoidant of human presence by adaptation to survive in offered ecological niches.

For 3 years, Christina Hansen Wheat has collected data coming from hand-reared wolves and dogs raised in comparable conditions to study differences (and similarities) between dogs and modern wolves. Researched litter representatives - as professionally raised young adult wolf siblings - in age of 7-10 months were adopted out to familiar European animal parks, where they are still visited by Christina (one of their former caretakers) always in company of same friendly emotions.

references:
Intrinsic Ball Retrieving in Wolf Puppies Suggests Standing Ancestral Variation for Human-Directed Play Behavior (2020); research by Christina Hansen Wheat, Hans Termin (Stockholm University).

Last year's December, I found two interesting news during few days of browsing North American websites. One of them encouraged to observe wild Yellowstone wolf packs' members as easy to notice on the fresh snow during consumption of hunted animal carcasses, in company of scavenging birds and competitive mesopredatory carnivores looking for their chance (it pointed on some data coming from current official Yellowstone reports).^[1] Whereas another one informed about a pair of Yellowstone National Park's wolf pups (confirmed as Junction Butte pack leading pair's offspring) fatal hit by a vehicle when they hung around a road - their den was localized nearby, likely caused by them getting used to human activity (sounds and smell of moving objects for example).^[2]

In the NPS Yellowstone status it stands clear:^[3]

Never feed wildlife. Animals that become dependent on human food may become aggressive toward people and have to be killed. Keep all food, garbage, or other smelly items packed away when not in use.

and

Never approach animals. The animals in Yellowstone are wild and unpredictable, no matter how calm they appear to be. The safest (and often best) view of wildlife is from inside a car. Always stay at least 100 yards (91 m) away from bears and wolves, and at least 25 yards (23 m) away from all other animals, including bison and elk.

And yet, according to recent Yellowstone Park press release, the "stay 100 yards away" rule was being repeatedly violated.

During the summer of 2019, the pack of 11 adults attended a den of pups near a popular hiking trail in the northeastern section of the park. Wanting to keep visitors and wolves apart, the park closed the den and surrounding area to the public. When the pups approached the trail and were in proximity to hikers, most people quickly moved away. However, some people violated the required 100-yard distance from wolves and approached the pups when they were on or near the trail to take a photo. Other people illegally entered the closed area to get near the wolves. Having grown accustomed to hikers, the pups then came close to visitors along a road.

— reported details^[4] suggest a human recurring appearance in the middle of those pups' developmental management's crucial stage, which includes a very short part of being socialisation-habituation extremely predisposed.

It made me think about Yellowstone wolves again. If they have shortened their flight zone - by adaptation to common visitors, scientists and wildlife observers, entire tourism in general - treating the offered environment like an ecological niche. Trimmed in such a way flight zone recalls taming as a defined process (in the context of each singular wolf), reduced reactivity if other species exists close by (including social behavior selective modification) and finally, adaptation to human presence itself (half-tamed animals - accidentally or in specific conditions allowing particular individuals to survive; and hand-reared - by skilled trainers / behaviorists / researchers / scientists or by not skilled, adventitious wolf-keepers).
Wildlife, as a set of multiplicitous ecosystems, defines all of plants (flora) and most of animals (fauna) living there without human influence or just not affected by human activity (otherwise, a wild animal is avoiding a human even when remaining in its natural habitat). Wild animals are not restrained by their natural environment, not tamed nor domesticated. Every species existence proceeds in keeping with its nature and instinct. Canis lupus in its natural habitat is an exemplary wild predator. Living in family packs it

• hunts (food finding prioritised)
• stays safe (active protection (intraspecific competition) or passive risk avoidance (interspecific competition))
• reproduces (an offspring as a main goal).

To sum up - it survives, where one of the conditions to be fulfilled is avoiding a human. If an animal is able to not be scared of human presence in a relatively close distance, it means that taming is possible. A tamed animal is a wild animal which previously adapted to humans in a natural way (socialization/habituation process) or by human intervention (animal training).

What's positive

• an animal is easy to observe, still living in its relatively natural habitat
• scientists, researchers and wolf lovers benefit for science, study and wolf advocacy - more knowledge, collected data, educated ranchers, farmers, citizens, social media sympathy.

And negative

• observer effect (Hawthorne effect) associated changes caused by awareness of being observed (optionally modified behavior), then adaptation to the situation (feeling safe consequence)
• unstable / unpredictable reactions and behaviors deviating from ethogram^[5] like scavenging on garbage instead of hunting destined preyed animals (resources reachable within ecological niche) or approaching too close to potentially dangerous objects (limited avoidance).

Recently reviewed book written by Elly Radinger was equipped with hand-held guide - in case of a scheduled trip to wolf inhabited regions accessible to visitors (vide Yellowstone National Park, USA) - and with instructions on how to behave in case a wolf meeting in wildlife (aimed at Germany).

Wild wolves' situation within the European area is generally different from their distant fellows. American wolves (Arctic, Timber and so on) are indeed easy to observe in wildlife - they live mostly in vast treeless territories, migrating between hunters trophy zones where to shoot them is allowed almost in every state. Wolves in Europe (Eurasian type) are difficult to encounter in wildlife - they migrate across the continent strictly protected by EU in the membership countries, hunting their destined prey in almost every forest.

Polish Association for Nature "WOLF" issued official rules dedicated to local residents, forest workers (forest rangers, foresters, lumberjacks), professionals (scientists, researchers, wolf watchers, wildlife photographers), common tourists and mushroom pickers - it precisely describes point by point how to act properly. It emphasises: to not feed wild animals intentionally,^[6] to keep garbage secured, to not leave food in camp places (even if they look cleaned up regularly), to take lunch leftovers away from forest workplaces and not set up temporary trashcans. The goal of it is to prevent the creation of the one of fundamental survival conditions indispensable for ecological niche to be adapted - a food resource reachability without a hazard.

If you are a wildlife photographer or a hunter, never provide meat to bait animals near hideouts, observation towers or balconies. Wolves, thanks to sensitive scent sense, can start to perceive humans as food management.

That rule concerns especially wolf youngsters (socialization/habituation aspect).

Polish road reports inform about approximately 50 wolves - among them some pups - confirmed fatally hit by car in 2019, above all in sections overlapping forest or field-forest areas.^[7] European road accidents' involving wild animals situation are strictly related to unlimited animal migration - by wildlife corridors (far from human activity, hazard avoidance) or just across random roads if such corridor is not available (danger ignored by frightened or determined animals).

Ecotourism and proper education are essential.

• Correctly interpreted ecotourism means usage of knowledge in practise like animal footprints to identify, ecosystem study or data to collect, trekking and hiking trips. It also means the ethical photography and wild animals observation from rigorous distance and in complete silence. If it progresses, ecotourism would correlate to profits (cabins rental, local souvenirs trade, guides payment).
• Correctly educated person balances teaching and learning implications - wildlife-human conflict decreases, wolf awareness increases. If it progresses, education is able to be passed in theory down to others (vide conversations, seminars), performed (vide presentations, workshops) and practised by ecotourists.

Both of them should always collaborate with each other.

^[1] NBC [Wyoming US, 16th Dec.2019]
^[2] OIL CITY NEWS [Montana US, 18th Dec.2019]
^[3] Yellowstone National Park regulations about wolves
^[4] NPS official release
^[5] Scientific description of a structure and its important components which are typical for selected species behavioral model, including instinctive reactions, rigid patterns and elastic habits, to make its representatives part of an established standard.
^[6] Feeders functionality should be reconsidered paying attention to terms of their necessity - scientifically and expertly justified.
^[7] Association for Nature "WOLF" [Poland, 31th Dec.2019]

According to Coppinger's theory, pre-dog domestication process itself ran based on natural selection: Most confident, social pre-dogs got used to living close to human settlements, eating garbage and bringing up safely their offspring (fire deterred other predators, like wild cats living and hunting alone). In exchange, humans gained warning about danger and deterring potential intruders (by mature pre-dogs). Relatively smaller/weaker individuals adapted to a diet containing leftovers (low quality, less protein, less calories), then gave up their predation and hunting/living in packs habits for half-solitary scavenging. Domestic dog became the first domesticated animal - entirely and certainly the first predator put through that human-focused process.

In association with their utility, dogs were generally divided into

• assisting humans during hunting (nomadic hunter-gatherers) - sight-hounds, scent-hounds
• dedicated pastoral types (sedentary farming, agriculture) - guarding dogs, herding dogs.

Sled dogs assisted newcomers during Early human migrations - they were  irreplaceable in transportation.

Siberian archaeozoological discovery previously confirmed the earliest evidence for dog breeding taking place on the remote Zhokhov Island, where Paleo-Arctic dwellers were supposed to hunt polar bears, then pursued reindeer to survive frigid temperatures on vast territory in animal-skin tents. Researchers suggest that discovered remains belong to dogs bred for pulling a sled (one of them could be a wolf-dog hybrid). A comparison of their skulls to wolf skulls and Siberian Husky's ones coming from that region, proved its Canis familiaris species affinity.

Current study hypothesises about the Inuit dogs being intentionally maintained to keep/enhance the unique features instead of local dogs being adopted in course of their migration across the continent. Siberian Inuit are descendants of migrants who crossed Beringia during the Paleolithic, expanding their indigenous Asian culture to Greenland, subarctic Eastern Canada and the North American Arctic regions. Those Paleo-Arctic dwellers supposed to hunt sea mammals, and wandered huge distances using water craft and dog sledges (sea ice, glaciers).

Basing on existing archaeological evidences, dogs weren't related to the North American Arctic before the Inuit arrival.

To test these hypotheses, we generated mitochondrial DNA and geometric morphometric data of skull and dental elements from a total of 922 North American Arctic dogs and wolves spanning over 4500 years.

The researched phenotype (morphological divergence) and genetic data (diversity) confirmed novel Inuit dogs larger with distinctive teeth shapes and proportionally narrower cranium, in comparison to their ancient fellows. It points on the Inuit dogs as specific type, predisposed to pull sledges through landscapes, on huge distances. Besides, the result analysed in the context of speculated locations and time periods showed dogs of the Inuit dominated regions genetically divergent from the rest local dog populations from 2000 years ago.

The genetic legacy of these Inuit dogs survives today in modern Arctic sledge dogs despite phenotypic differences between archaeological and modern Arctic dogs.

Along with advancement of civilisation, dog breeds^[1] were shaped consistently by selection related to their utility - together with exemplary appearance and behavior - required for particular tasks. In harmony with their own standard, some offspring were picked out from every litter in order to let them survive and pass their genes to next generations. Among them 'ancient breeds'^[2] kept the genome almost unchanged (in comparison to Canis lupus genome); they're considered to come directly from a common ancestor.

Modern sled dogs remained culturally and economically important for traditional Arctic residents - still preferred as form of transport, even if their number declines inversely due to climate changes (the natural environment losses) or recurring dog diseases (mobility, tourism); their popularity likewise steps aside technological progress (lifestyle changes, snowmobiles). However, dogs pulling sleds by snow fields stay essential part of autochthonic Arctic identity.

references:
Specialized sledge dogs accompanied Inuit dispersal across the North American Arctic (2019); study by collective work
Archaeological dogs from the Early Holocene Zhokhov site in the Eastern Siberian Arctic (2017); research by Vladimir V. Pitulko, Aleksey K. Kasparov (Russian Academy of Sciences)
Coppinger Raymond, Lorna; „Dogs. A Startling New Understanding of Canine Origin, Behavior, and Evolution” (2002), "What is a dog?" (2015), "How Dogs Work" (2016)

^[1] Breed means a group of individuals within the species, being characterised by a set of mutual, shared, noteworthy attributes, inherited - and solidified - by generations.
^[2] Genetically divergent from the modern breeds - Basenji, Saluki, Afghan hound, Samoyed, Canaan dog, New Guinea singing dog, Chow Chow, Chinese Shar Pei, Akita, Alaskan malamute, Siberian husky, American Eskimo dog and Canis lupus dingo. - citation after Genome-wide SNP and haplotype analyses reveal a rich history underlying dog domestication (2004), study by collective work.

Almost a quarter of a century passed by since the first wolf individuals were released into the open park boundary, as the missing element in its natural ecosystem to be balanced, with a hope they would settle there permanently.^[1] Over the years, starting from 14 ones reintroduced to Yellowstone initially, constantly studied and monitored^[2] wolf population has fluctuated, split up into the northern perimeter and the interior habitat. It counted 80 in 2018 - 9 wolf packs ranged from 3 to 19.

This is the first year since 1995 we recorded no intraspecific-caused mortality, which is usually the leading cause of natural mortality in the park.

First time in history of the wolf reintroduction to the Yellowstone no such accident was confirmed on the limited NPS area where the local wolf population remains divided into neighbouring or overlapping each other territories taken over by specific wolf packs. That territorial stalemate make them remain seemingly unconflicted.

Statistically, direct territorial conflict involving two different groups of inhabitants, is the second - right after human activity like culling, poaching, road collisions (cars) - wolf death cause. Wolf packs confront territorial behavior (intra-specifically) toward potential intruders (same species representatives) within inhabited - scent marked - regions. Those fights are silent - excluded vocalisation (warning signals elided) - determined by the number of adult males in a pack.

In nature, wolves migrate - through still unsettled (by wolf species) areas or between territories marked by other wolf residents. In principle, those are young, healthy individuals, satelliting outside to find a partner (mating season) and back to the family pack (inbred diversity aspect). As the result, local wolf population temporarily
– increases - thanks to wild outsiders coming inside
– decreases - because of local roamers venturing outside being hit by a car / shot by a hunter / trapped by a poacher (human activity again).

Overall, wolf numbers fluctuated little from 2009 to 2017 (83-108 wolves) but dropped slightly this year, particularly in the interior of Yellowstone.

Wolf pack's territory is set down in order to long-term food resources being optimally sufficient. It consists of
– inner part - randez-vous meeting place, where wolf family pack spends most of time (incl. wolf den)
– outer part - hunting area, where marked borders are patrolled and guarded by adult pack members.
More numerous potential prey population (in reference to overall area), less vast single pack's territory (and more chance to reside for other wolf packs). To sum up, if food resource amount is sufficient, neighbouring wolf packs share the same hunting area, even if their territories overlap with one another (each one containing its own randez-vous point). Competition rate correlates also to mutual inbred, especially regarding leading pairs in the neighbourhood.

Counting 80, Yellowstone population, which has declined regularly for last 5 years, reached its lowest number in history - circa half of the highest wolf numbers in early 2000's. According to Doug Smith, the Yellowstone Wolf Project leader, it's strictly related to the local elk population - almost 20000 in 1995 (when the Yellowstone wolf reintroduction was started), currently limited by Yellowstone wolves to safely numbered 6000-8000.

citations/references:
Yellowstone Wolf Project archive
Elli H. Radinger "The Wisdom of Wolves" (2019); reviewed

^[1] Before that, captured and transported from Canada, obligatory placed in fenced enclosures and fed elk carcass to make them adapt to the diet.
^[2] Each wolf pack within the Yellowstone park area counts at least one (leading male/female) pack member radio-collared. 7 wolf generations were researched so far.

Switzerland keeps being a pioneer and leader in herd management experiments since 1999, which means using passive non-lethal methods like fladry and/or fences to protect livestock against predators, and active non-lethal methods like shepherds (herding dogs) and sheepdogs (livestock-guarding dogs) supporting correspondingly - a herder (by cooperation) and a sheepherder (independently).

A social guard dog is selected for its character, to bond with other animals. Therefore the dog must be a social animal, that is surrounded by other social animals. This is the reason why the dog cares for the sheep, as they satisfy their need for companionship.^[1]

Livestock-guarding dogs work autonomously. Seemingly diurnally lethargic, they revive nocturnally - reacting to every suspect noise or movement, barking loudly using low tones, bravely looking straight into potential intruder's eyes. Every factor depends on danger rate (responding with tail wagging, invitation to play, simulated charging). Immediate reaction to approaching strangers (predatory animal, unrecognised person) is essential - LGD intends to distract an intruder closing in, to prevent a potential attack on grazing animals within protected pasture.

• socialized with livestock / cattle / other herded animals (farmer's decision)

Socialization (then habituation) is important - if not the most important - aspect of companion animal behavior, founding a base rooted in developmental offspring management - a critical period when the socialization process will be finalised permanently. To initiate it correctly, puppies should be placed directly in the sheepfold or on the grazing land (moved from time to time, to provide familiarity with the entire herd), in safe kennels (preventing potential inventory attacks) where they sleep, eat and drink water. The whole training process is finished with the sheepdog's development finale (ability to reproduce) - the young sheepdog is released into open area.

• limited in contact with humans

Domestic dog species evolved passing by predispositions to remain human focused in a natural way (inter-specific cooperation) or by human intervention (selective breeding). Elementary social behavior transferred into regular play behavior (teamwork foundation), bounds dog-human relations during sensitive period (developmental puppy management), making that connection more and more attractive to a dog. In the context of LGD training process, a dog-human contact (including limited social reward within a target environment) tends to remain reduced to the owner and family (basic needs providence - like food/water resources, safety - and livestock inspection). Otherwise, a trained guarding dog would become a casual dog abandoning the guarded herd because a human companion is preferred.

• not aggressive towards guarded animals

Mature livestock-guarding dog, accepted by grazing animals, can work standalone, without human supervision. It's a dog which reacts permissively or submissively, when sniffed by them - avoiding eye contact, putting ears back and tail down. Handler's role is to observe and spot deviating behaviors on time (instinctive bite inhibition out of control, prey drive being triggered, partial predatory sequence simulation) yet while the specific guardian dog is trained, and do not strengthen them or motivate repetitive attempts.
Due to previously collected experiences - being obligatory socialized to herded animals precisely, in the most adaptive primary developmental part - familiar non-human animals become 'imprinted' to LGD as fellow relative-likes.

• fearless, but not offensive, to a distant approacher considered as intrusive

Typical guard dogs should be heavy (up to 75kg) and large (up to 70cm). In action, guarding with a tail held up, barking determinate to charge on the source of menace, which causes an intruder to back off in order to avoid confrontation or by decision that the risk is not adequate to uncertain benefits.
Evolutionary, large sizes give guarding dogs a fearsome presence (in pair with a chance to work safe within the independently patrolled territory), make them stronger (assertive movement, fracture-immune bones) and better prepared to harsh weather conditions (cold resistance, loss warm prevention). Unified color is another adaptation passed on through genes, correlated to geographical locations where specific LGD breeds came to existence - it gives the natural camouflage (vide white mountain dogs guarding sheep in the snow covered areas or Caucasian Shepherd Dogs originally working in the rocky regions).

Looking at the adolescent dog type related sequenced predatory behavior - its canine prey drive was shaped originally to create the working dog dedicated to guarding only.

SEARCHING -> TRACKING -> STALKING -> CHASING -> GRABBING -> KILLING -> DISSECTING -> EATING

Historically, dogs which were able to attack the livestock could be used to hunt (or to herd if attack tendency was partial or moderate), whereas those which still presented youthful behavior as an adult and didn't have a drive to herd or hunt, became the perfect guarding ones. Their prey drive remained permanently and almost completely weakened.

From a behavioral perspective, LGD are predestined to interrupt a predatory sequenced behavior - to antecede SEARCHNG / TRACKING chains detected in the case of roaming wild predator or STALKING chain detected in the case of hunting one. It must be done exactly before CHASING is activated (starting from that chain prey drive is triggered and wild Canis predatory sequence is unstoppable).

So, their job is to locate potential predator and to deter it. Exemplary Polish Tatra Sheepdog doesn't try to attack the approaching predator (in order not to leave the livestock unattended) but gather up the sheep and stand by them instead; Central Asian Shepherd Dogs were bred strictly to protect the livestock against apex-predatory wolves. Both LGD breeds are territorial, protective and make fully independent decisions.

Livestock guarding dogs are territorial, and they are protective of what they believe is theirs. The “resource-guarding” that we find so unacceptable in most dogs is exactly what we desire in a guardian dog.

- Ken Ramirez says, a professional dog trainer in Karen Pryor Clicker Training Academy (KPCT), who took care of a 2-years-old female Maremma sheepdog, trained LGD for his Ranch protection because of coyotes' appearance. -

LGD are reinforced by seeing outsiders and predators leave when they bark. Ranchers who are instructed to let the dogs “feel that they are in charge” are less likely to discipline nuisance behaviors and lower the dogs’ confidence. A confident dog bred for territorial aggression will claim more territory than an insecure dog. Ranchers who are instructed to let the dogs “feel that the herd is theirs” will have the dogs sleep with the herd, establishing the dogs’ territory.^[2]

Owners of Polish Tatra Sheepdogs living as companion animals (at home, in towns) report that their dogs are inclined to watch over their family by patrolling regularly every room, looking after children and remaining pets.

references:
Coppinger Raymond, Lorna "What Is a Dog?" (2016), "How Dogs Work" (2015)
"Poradnik ochrony zwierząt hodowlanych przed wilkami" SdN "WILK" (2016)

^[1] KORA, Carnivore Ecology and Wildlife Management report (August 1999)
^[2] Tulip Joins the Ranch

Some time ago, certain photo re-appeared - an endangered^[1] Himalayan wolf species female being mated by a free-ranging domestic dog. The photo comes from the Field report led by Lauren Hennelly in Spiti Valley, India, dated 2015.

Notice: Himalayan wolf [Canis himalayensis] is genus Canis representative, where the gray wolf [Canis lupus] species belongs as well. Its taxonomic status - of being a gray wolf subspecies - stays under discussion.

That's nothing new - an international study published last year confirmed that approximately 60% of Eurasian grey wolf genomes carries domestic dog marked DNA on their gray wolf gene pool, which suggests wolf-dog cross-bred geographically widespread in Eurasia for hundreds of years (confirmed as less frequent phenomenon in North America).

Despite the evidence of hybridisation among Eurasian grey wolves, the wolf populations have remained genetically distinct from dogs, suggesting that such cross-breeding does not diminish distinctiveness of the wolf gene pool if it occurs at low levels.^[2]

Recent study - supervised by the Lincoln’s University of Nebraska, in collaboration with Qinghai University in China - suggests that in the distant past, Tibetan mastiffs (as a domestic dog type of breed) could survive in harsh, low-oxygen high mountains' environment thanks to being randomly hybridised with mountain wolf individuals (vide Tibetan wolf), by gaining hypoxia tolerance.

Notice: Tibetan wolf [Canis lupus laniger] is a gray wolf [Canis lupus] subspecies (Eurasian wolf [Canis lupus lupus] precisely), genetically Himalayan wolf [Canis himalayensis] similar (ecological niche), rooted to Holarctic gray wolf originally (wolf migrations).

It is the first study showing that an evolutionary adaptive gene mutation (two amino-acid tweaks altered) of the high-altitude species were selectively introgressed into another one.

The research results stand that Tibetan mastiff’s hemoglobin  - the iron-containing protein carrying oxygen in blood - architecture absorbs-releases oxygen circa 50% more efficiently than in case of other dog breeds (absent in also researched samples - half-Great Pyrenees and half-Irish wolfhound), especially under thin-air conditions. It hypothesises that an inactive dual mutation, laying dormant in the wolf subspecies genotyp, was passed into the corresponding segment of a similar active gene in the domestic mustiff's one.

There had been no direct evidence documenting that, yes, these two unique mutations have some beneficial physiological effect that is likely to be adaptive at high altitude.

— Jay Storz says, professor of biological sciences, the research leader.^[3]

What we’ve discovered is one of the reasons why the Tibetan mastiff is so different from other dogs. And that’s because it’s borrowed a few things from Tibetan wolves.

Tibetan mustiff is a Molosser - large type - dog, historically bred to herd flocks in Tibet and protect sheep grazing on pastures from predatory attacks taking place up to 4000-5000 metres above sea level, where local wolves were apex. Those are heights which no other dog breed - or an average free-ranging dog - is not able to survive.

In the inheritance context, it puts hybridity process under reconsideration - is it indeed a one-sided, negative process.

Both, local Himalayan wolf population and Tibetan wolves, naturally inhabit Tibet - dispersed within the Tibetan Plateau territory (therein Tibet Autonomous Region (TAR) and partial Himalayas), still independent genetically unaffected by domestic dog's instinctively human-associated nature.

references:
Himalayan wolf and feral dog displaying mating behaviour in Spiti Valley, India, and potential conservation threats from sympatric feral dogs (2015); Lauren Hennelly, Bilal Habib, Salvador Lyngdoh (Department of Animal Ecology and Conservation Biology, Wildlife Institute of India)
A new macroecological pattern: The latitudinal gradient in species range shape (2018); research by group work
Adaptive Changes in Hemoglobin Function in High-Altitude Tibetan Canids Were Derived via Gene Conversion and Introgression (2019); research by group work

^[1] Himalayan wolf population counts 350 (1995) for Ladakh and Himachal Pradesh as its natural habitat. Officially listed as protected by Schedule I of the Wildlife Protection Act 1972.
^[2] citation after ScienceDaily (March 21st, 2018) via "New genetic research shows extent of cross-breeding between wild wolves and domestic dogs"
^[3] citations after University of Nebraska–Lincoln (Nebraska Today; Sep.4th, 2019) via "Wolf hack: Study details how Tibetan dog got oxygen boost"

Fear of predators, as the primal one, is a natural reaction of preyed animals in wildlife. Fear response is an important functionality which forces strategies being used in the survival aspect - all of them part of the detailed 5F rule

– Flight
– Freeze (motionlessness of an alert animal, or tonic immobility - a state of paralysis)
– Faint (playing dead)
– Fiddle about (negotiations, submission, calming signals - typical behavior of social animals)
– Fight

where escape option (prioritised by preyed animals and wild animals in human presence) and optional attack (avoided if possible) - "Flight or Fight" mechanism driven by fear - are placed on clearly opposite sites.

Flight distance is evolutionary related to prey-predator based ecosystems. Chased prey aims for overtaking its own scent, intending to escape a predator (vide canine prey drive finished by killing to eat a hunted food resource) and to prevent reiterated action (vide canine prey drive started by tracking to stalk a hunted food resource). In the behavioral ecology range, it is also related to such complex aspects like natural population management and trophy cascade discussion. Fear of predators triggers naturally prey-typical behavior - grazing animals stay emotionally vigilant, reacting instinctively to every change nearby within the inhabited area.

Study by University of Western Ontario, via Scientific Reports, argues that PTSD-like changes in brains of wild animals may be caused by their natural fear of predators. Constant traces left in the neural circuitry in pair with constantly induced fearful behavior seem to be comparable to Post-Traumatic Stress Disorder - a result of trauma after extremely emotional - and/or frequently iterated - experience a priori being a stressor which is a threat to life or exposure to danger - at the critical point triggered by fear or just an impendency.

• It suggests that traumatic stress, as an enduring behavioral influence, can be considered as animal PTSD model in the context of survival in wildlife

Study was based on wild-caught, black-capped chickadees at Western's Advanced Facility for Avian Research (AFAR), exposed to predatory and non-predatory birds' vocalisation (audio playbacks), for 2-days period of time; then housed together and not exposed, for 7-days period (research analysis requirement).

• It implicates PTSD as a natural response for an emotional trauma

In nature, fear is strictly connected to hazard avoidance as avoidance anticipation (vigilance) and emotional inhibition (toward reactivity); associated with amygdala as the limbic system primal structure and noradrenalina/adrenalina as fundamental neurotransmitters responsible for every immediate reaction (short route emotional stimulus -> amygdala) finalised by relief (dopamine level increased back). Long-term stress (vide trauma) initiates the learning process (memorising) involving other limbic structures, like hippocampus in charge of consolidation short-term memory to long-term one and cortisol so-called 'stress hormone' (long route emotional stimulus -> sensory cortex -> amygdala).

"Our findings support both the notion that PTSD is not unnatural, and that long-lasting effects of predator-induced fear with likely effects on fecundity and survival, are the norm in nature" - Liana Zanette explains, one of the research leaders.

Fear can be measured in the brain and fearful life-threatening events can
leave quantifiable long-lasting traces in the neural circuitry of the brain with
enduring effects on behaviour, as shown most clearly in post-traumatic stress
disorder (PTSD).

citations after:
Predator-induced fear causes PTSD-like changes in the brains and behaviour of wild animals (2019); research by collective work
Fear of predators causes PTSD-like changes in brains of wild animals; Science Daily (August 12th, 2019)