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Post by brobear on Apr 1, 2022 3:55:37 GMT -5
So, why post a topic about the 'Siberian Tiger Project' here in 'Bears in General'? *Because this is where tigers have been closely monitored: SIBERIAN TIGER PROJECT russia.wcs.org/en-us/projects/siberian-tiger-project.aspx About 500 Siberian or Amur tigers are left in the wild, with 95% of them in the Russian Far East. Within the tiger’s range in Russia, the largest protected area is the Sikhote-Alin Biosphere Reserve, a 400,000 ha (4000 km2) reserve that has been a stronghold for the Amur tiger since its creation in 1935, and which harbors over 30 tigers today. In 1992 WCS (initially as the Hornocker Wildlife Institute) in cooperation with the Sikhote-Alin Reserve began intensive studies of tiger ecology under the Siberian Tiger Project, today the world’s longest running radio-telemetry based tiger research and conservation effort. *Note: for the last 30 years, tigers have been closely observed. If there were any truth to the imaginary fantasy of the tiger fanatics' claims of large male tigers stalking and killing adult male Ussuri brown bears, then surely after 30 years of close observation, there would be strong evidence confirming these wild accusations. But no.
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Tiger
Apr 1, 2022 7:54:10 GMT -5
Post by brobear on Apr 1, 2022 7:54:10 GMT -5
Central Sikhote-alin www.yichuans.me/datasheet/output/site/central-sikhote-alin/ The Sikhote-Alin mountain range is one of the world’s most distinctive, diverse and unusual temperate forests where the natural ecosystems are almost pristine as a result of its relative isolation, the difficulty of access, its sheer size, the denseness of its forests and over 60 years of protection. In a region stretching from the peaks of Sikhote-Alin to the Sea of Japan endangered subtropical species such as Amur tiger and Himalayan bear live alongside northern species such as brown bear and elk. The site is important for the survival of many endangered species, and for a temperate region the level of endemic plants and invertebrates is extraordinarily high. It has been threatened by logging interests. Fauna: Central Sikhote-Alin has fifteen biogeographical faunal assemblages which include 65 mammals, 241 birds, 7 amphibians, 10 reptiles and 51 fish. A unique feature of the Primorye region is the intermingling of species at their northern or southern limits of distribution. The Sikhote-Alin Mountains are the southern limit for boreal species such as wolverine Gulo gulo, and the northernmost limit for subtropical species like the Amur tiger Panthera tigris altaica (CR). This is by far the most charismatic species of the region. The total of adult tigers in the Russian Far East was put between 330 and 370 (plus 100 cubs), many of them in the Sikhote-Alin mountains but only some 10-15 tigresses in the Preserve itself, by the Siberian Tiger Project in 2005. Male tigers can have very large territories indeed and their numbers are known with less certainty. However the numbers given in the nomination document in and around the Preserve and Bikin valley from 1994 to 1999 fluctuated between 26 and 52, averaging 38, the most in any protected area. And in 2009 the Phoenix project noted 30-50 tigers were known in the Bikin valley, their home-ranges reaching into the neighbouring Khor and Bol’shaya Ussurka valleys and to the coast. The Bikin valley serves as a reproductive centre for the northeastern group of these tigers. 31 of the 65 mammals are concentrated in the pine-broadleaf forest belt and in the valleys and floodplains of the larger rivers which contain high numbers because of the high density of suitable habitats. These include red squirrel Sciurus vulgaris. ermine Mustela erminea, sable Martes zibelina, Himalayan black bear Ursus thibethanus (VU), wild boar Sus scrofa, and Manchurian red deer Cervus elaphas xanthopygus, all of which are hunted commercially by the local human population. On the mountains northern pika Ochotona hyperborea, yellow-throated marten Martes flavigula and musk deer Moschus moschiferus are found. Other mammals include Manchurian hare Lepus mandschuricus, wolf Canis lupus, Asiatic wild dog Cuon alpinus (EN), brown bear Ursus arctos, Eurasian otter Lutra lutra, Siberian weasel, Mustela sibirica, mink Neovison vison, lynx Lynx lynx, Amur leopard cat Prionailurus bengalensis euptilura, wild hog Sus scrofa, Altai maral or elk Cervus canadensis sibiricus, Ussuri moose Alces alces cameloides, Sika deer Cervus nippon, Siberian roe deer Capreolus pygargus, and long-tailed goral Naemorhedus caudatus (VU). Many of these animals have evolved a close trophic interdependence on the Korean pine-nut. Offshore, harbour seals Phoca vitulina are seen. Of the 241 species of birds recorded in the nomination, 72% are nesting species, the rest are overwinterers, summer migrants or vagrants.130 breeding species are found in the Sikhote-Alin Preserve, 40-45 species in the pine-broadleaf forest, almost 40 species in the pine-spruce forest and 30-35 species in the fir-spruce forest. The various ecosystems provide habitat for 38 rare species. On the coastal cliffs are the endemic spectacled guillemot Cepphus carbo and Japanese cormorant Phalacrocorax capillatus, the white-tailed sea-eagle Haliaëetus albicilla, Pacific swift Apus pacificus and hill pigeon Columba rupestris. In the lower reaches of the river, red-crowned crane Grus japonensis (EN), hooded crane Grus monacha (VU), oriental stork Ciconia boyciana (EN), black stork Ciconia nigra, yellow-legged buttonquail Turnix tanki, far eastern curlew Numenius madagascariensis (VU), oriental honey-buzzard Pernis ptilorhyncus and grey-faced buzzard Butastur indicus are present. The valley forests of the middle reaches are inhabited by osprey Pandion haliaetus, mandarin duck Aix galericulata, brown hawk-owl Ninox scutulata, Chinese merganser Mergus squamatus (EN) and Blakiston's fish-owl Ketupa blakistoni (EN). The upper river reaches covered by larch, conifer and stone birch forests, provide refuge for capercaillie Tetrao parvirostris and Siberian spruce grouse Falcipennis falcipennis. The alpine tundra is the home range of white-throated rock thrush Monticola gularis and Hodgson's hawk-cuckoo Cuculus fugax. There are 7 species of amphibians and 10 species of reptiles, including the rare and endemic species Amur racer Elaphe schrenki, redbacked racer E. rufodesata, brown mamushi Agristrodon saxatili, the Ussuri mamushi A. blomhoffi and the lizard Takydromus amurensis Because the region’s river system evolved during the Miocene, subsequent relatively stable environmental conditions have enabled the evolution of specialised populations of fish. Within the Bikin River basin, 51 species from 15 families have been identified. There are many endemic and valuable species, including the Far Eastern brook lamprey Lampetra reissneri. A close trophic relationship exists between Blakiston's fish-owl and its main prey Arctic grayling Thymallus arcticus and lenok Brachymstax lenok, which in turn rely on the uncontaminated state of the rivers. Of the insect fauna, 28 species are included in the Red Data Book of the Russian Federation, of both southern and northern origins.
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Tiger
Apr 1, 2022 8:01:59 GMT -5
Post by brobear on Apr 1, 2022 8:01:59 GMT -5
Ussuri Brown Bear animals.fandom.com/wiki/Ussuri_Brown_Bear The Ussuri brown bear (Ursus arctos lasiotus), also known as the black grizzly is a population of the brown bear. One of the largest brown bears, Ussuri brown bears approach the Kodiak brown bear in size. It is very similar to the Kamchatka brown bear, though it has a more elongated skull, a less elevated forehead, somewhat longer nasal bones and less separated zygomatic arches, and is somewhat darker in color, with some individuals being completely black, a fact which once led to the now refuted speculation that black individuals were hybrids of brown bears and Asian black bears. Adult males have skulls measuring 38.7 cm (15.2 in) long and 23.5 cm (9.3 in) wide. They can occasionally reach greater sizes than their Kamchatka counterparts: the largest skull measured by Sergej Ognew(1931) was only slightly smaller than that of the largest Kodiak brown bear (the largest subspecies of brown bears) on record at the time. On Shiretoko Peninsula, especially in the area called "Banya", many females with cubs often approach fishermen and spend time near people. This unique behavior was firstly noted more than a half century ago, with no casualties or accidents ever recorded. It is speculated that females take cubs and approach fishermen to avoid encountering adult males. In Sikhote Alin, Ussuri brown bears den mostly in burrows excavated into hillsides, though they will on rare occasions den in rock outcroppings or build ground nests. These brown bears rarely encounter Asian black bears, as they den at higher elevations and on steeper slopes than the latter species. They may on rare occasions attack their smaller black cousins. In middle Sakhalin in spring, brown bears feed on the previous year's red bilberry, ants and flotsam, and at the end of the season, they concentrate on the shoots and rhizomes of tall grasses. On the southern part of the island, they feed primarily on flotsam, as well as insects and maple twigs. In springtime in Sikhote Alin, they feed on acorns, Manchurian walnuts and Korean nut pine seeds. In times of scarcity, in addition to bilberries and nuts, they capture larvae, wood-boring ants and lily roots. In early summer, they will strip bark from white-barked fir trees and feed on their cambium and sap. They will also eat berries from honeysuckle, yew, Amur grapevine and buckthorn. In southern Sakhalin, their summer diet consists of currants and chokeberries are eaten. In the August period in the middle part of the island, fish comprise 28% of their diet. In Hokkaido, the brown bear has a diet including small and large mammals, fish, birds and insects such as ants. Recent increases in size and weight, reaching 400 kg (880 lb), or possibly up to 450 kg (990 lb) to 550 kg (1,210 lb), are largely caused by feeding on crops.
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Tiger
Apr 1, 2022 8:03:12 GMT -5
Post by brobear on Apr 1, 2022 8:03:12 GMT -5
Ussuri Brown Bear continued: Range and status: The brown bear is found in the Ussuri krai, Sakhalin, the Amur Oblast, northward to the Shantar Islands, Iturup Island, northeastern China, the Korean peninsula, Hokkaidō and Kunashiri Island. Until 13th century, bears inhabited the islands of Rebun and Rishiri, having crossed the La Pérouse Strait to reach them. They were also present on Honshuduring the last glacial period, but were possibly driven to extinction either by competing with Asian black bears or by habitat loss due to climate change. One of three genetic groups, being distinct for at least more than 3 million years and respectively reached to Hokkaido on separate periods through different routes, entered Hokkaido through Honshu.
About 500–1,500 Ussuri brown bears are present in Heilongjiang, and are classed as a vulnerable species. Illegal hunting and capture has become a very serious contributing factor to the decline in bear numbers, as their body parts are of high economic value.
Five regional sub-populations of Ussuri brown bears are now recognized in Hokkaido. Of these, the small size and isolation of the western Ishikari subpopulation has warranted its listing as an endangered species in Japan’s Red Data Book. 90 to 152 brown bears are thought to dwell in the West Ishikari Region and from 84 to 135 in the Teshio-Mashike mountains. Their habitat has been severely limited by human activities, especially forestry practices and road construction. Excessive harvesting is also a major factor in limiting their population.
In Russia, the Ussuri brown bear is considered a game animal, though it is not as extensively hunted as the Eurasian brown bear.
In Korea, a few of these bears still exist only in the North, where this bear is officially recognized as natural monument by its government. Traditionally called Ku'n Gom (big bear), whereas black bears are called Gom(bear), the Ussuri brown bear became extinct many years ago in South Korea largely due to poaching. In North Korea, there are two major areas of brown bear population: including JaGang province and HamKyo'ng Mountains. The ones from JaGang province are called RyongLim Ku'n Gom(RyongLim big bear) and they are listed as Natural Monument No.124 of North Korea. The others from Hamkyo'ng Mountains are called GwanMoBong Ku'n Gom(GwanMo Peak big bear) and they are listed as Natural Monument No.330 of North Korea. All big bears(Ussuri brown bears) in North Korea are mostly found around the peak areas of mountains. Their average size varies from 150 kg to 250 kg for Ryonglim bears found in the area south of Injeba'k Mountain, up to average of 500 kg to 600 kg for the ones found in the area north of Injeba'k Mountain.
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Tiger
Apr 1, 2022 8:04:53 GMT -5
Post by brobear on Apr 1, 2022 8:04:53 GMT -5
Attacks on humans: In Hokkaido, during the first 57 years of the 20th century, 141 people died from bear attacks, and another 300 were injured. The Sankebetsu brown bear incident (三毛別羆事件 Sankebetsu Higuma jiken?), which occurred in December 1915 at Sankei in the Sankebetsu district was the worst bear attack in Japanese history, and resulted in the deaths of seven people and the injuring of three others. The perpetrator was a 380 kg and 2.7 m tall brown bear, which twice attacked the village of Tomamae, returning to the area the night after its first attack during the prefuneral vigil for the earlier victims. The incident is frequently referred to in modern Japanese as bear incidents, and is believed to be responsible for the Japanese perception of bears as man-eaters. The Ainu people worship the Ussuri brown bear, eating its flesh and drinking its blood as part of a religious festival known as Iomante.
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Tiger
Apr 1, 2022 8:05:51 GMT -5
Post by brobear on Apr 1, 2022 8:05:51 GMT -5
Interactions with tigers: Ussuri brown bears are occasionally preyed on by Siberian tigers, and constitute about 1% of their diet (and up to 18.5% together with black bears in very particular cases). Siberian tigers regularly prey on young bears but adult female Ussuri brown bears are also taken outside their dens as well. Siberian tigers most typically attack brown bears in the winter in the bear's hibernaculum. They are typically attacked by tigers more often than the smaller black bears, due to their habit of living in more open areas and their inability to climb trees. When hunting bears, tigers will position themselves from the leeward side of a rock or fallen tree, waiting for the bear to pass by. When the bear passes, the tiger will spring from an overhead position and grab the bear from under the chin with one forepaw and the throat with the other. The immobilised bear is then killed with a bite to the spinal column. After killing a bear, the tiger will concentrate its feeding on the bear's fat deposits, such as the back, legs and groin. Tiger attacks on bears tend to occur when ungulate populations decrease. From 1944 to 1959, more than 32 cases of tigers attacking bears were recorded in the Russian Far East. In the same period, four cases of brown bears killing female and young tigers were reported, both in disputes over prey and in self-defense. Gepnter et al. (1972) stated bears are generally afraid of tigers and change their path after coming across tiger trails. In the winters of 1970–1973, Yudakov and Nikolaev recorded 1 case of brown bear showing no fear of the tigers and another case of brown bear changing path upon crossing tiger tracks. Despite the possibility of tiger predation, some large brown bears may actually benefit from the tiger's presence by appropriating tiger kills that the bears may not be able to successfully hunt themselves and follow. During telemetry research in the Sikhote-Alin protected area, 44 direct confrontations between the two predators were observed, in which bears were killed in 22 cases, and tigers in 12 cases.
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Post by brobear on Apr 1, 2022 8:10:52 GMT -5
Quote: From 1944 to 1959, more than 32 cases of tigers attacking bears were recorded in the Russian Far East. *32 known cases of bears attacked by tigers in a 15-year period. Roughly two tiger attacks per year. *Note: of course tigers kill more than two bears per year, but there were never any sizable number of bears killed per year. With the exception of the extremely rare individual like Dale, who had acquired an unusual taste for bear flesh ( a freak occurrence ), bears make up the smallest percentage of meat consumed by a tiger. Also note, that bear remains found within tiger droppings comes largely from found carrion. mnzoo.org/blog/animals/amur-tiger/ Amur tigers are carnivores. They eat mostly large mammals, especially wild boar and deer. But when food is scarce or a hunt goes badly (many do), they may turn to smaller prey such as rabbits or to carrion. www.thoughtco.com/what-is-a-tiger-129743 Tigers are carnivores. They are nocturnal hunters that feed on large prey such as deer, cattle, wild pigs, rhinoceroses, and elephants. They also supplement their diet with smaller prey such as birds, monkeys, fish, and reptiles. Tigers also feed on carrion.
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Tiger
Apr 3, 2022 1:41:47 GMT -5
Post by brobear on Apr 3, 2022 1:41:47 GMT -5
Brown bear protection and use in the Sikhote-Alin www.researchgate.net/publication/276160836_Brown_bear_protection_and_use_in_the_Sikhote-Alin The brown bear in the Sikhote-Alin is used as a hunting resource, however management problems exist; primarily in that there is no system of population monitoring in place. The primary threats to population persistence are poaching, habitat reduction and range fragmentation. Recommendations for brown bear protecrion and rational use in the Sikhote-Alin are proposed. ... Second, there is the necessity for conservation and rational management of these species. The Siberian musk deer and bears are game animals, and products derived from their bodies are in high demand, which creates additional problems with maintaining the well-being of their populations
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Tiger
Apr 3, 2022 1:45:13 GMT -5
Post by brobear on Apr 3, 2022 1:45:13 GMT -5
Behavior of Brown Bears During Feeding in the Sikhote-Alin www.sciencedirect.com/science/article/pii/S207815201630027X Feeding methods and habits of brown bear in Sikhote-Alin are varied and specific for each type of feeding behavior depending on the composition and condition of food, its availability and abundance, season, animal's sex, age, physical condition, personal preferences and experience, the presence of competitors and disturbance from other predators and humans. A feature of the feeding behavior of bears in Sikhote-Alin is consumption of the remains of meals of tigers. Brown bears (Ursus arctos) in Sikhote-Alin (Russian Far East) prefer pine–broad-leaf and broad-leaved forests. The diet of bears in the region is widely varied (Bromlei, 1965, Seryodkin, 2012), which leads to behavioral diversity of the species associated with procuring and consumption of food. The study of traces of life activities of animals allows the researchers to determine the diet of the bear and the characteristics of its food-procuring behavior, which is important for the assessment of the predator population and development of scientific measures for its control. This paper is based on the author's research conducted in Sikhote-Alin in 1998–2015, as well as on literature review.
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Tiger
Apr 3, 2022 1:46:42 GMT -5
Post by brobear on Apr 3, 2022 1:46:42 GMT -5
Behavior of Brown Bears During Feeding in the Sikhote-Alin - continued: Herbaceous vegetation is essential in the diet of Sikhote-Alin brown bears from May till August, and stays in the diet in September as well. The animals spend much time in floodplains of rivers and creeks where the most juicy and dense vegetation grows. Here they graze in mass feeding on aerial parts of grass, as well as underground parts of some species of plants.
The most common among the traces of grass eaten by bears is the remains of Tatewaki butterbur (Petasites tatewakianus) — 80% of all traces. Bears often eat the leaves completely off the young plants of this species up to 15 cm high. For more mature plants only leafstalks are consumed, while leaf blades are not used for food. When grazing a bear grabs a juicy leafstalk at the bottom with its teeth and pulls it. The leaf with most of the stalk breaks off, and at the remaining part of the stalk revolute fragments of the tissue are formed (Fig. 1). In plants of Umbelliferae family (hogweed — Heracleum spp., angelica — Angelica spp.) bears prefer to eat the stems and leafstalks (Bromlei, 1965). The animals usually feed on butterbur, angelica and hogweed up to the point of almost complete consumption of these plants in the places of their local habitat. Bears consume the entire vegetative part of many species of grass — leaves with the stem (Corydalis ochotensis, Urtica angustifolia, Impatiens noli-tangere, Filipendula palmate, etc.). At leisure grazing in floodplains bears trample down the grass leaving clearly discernible tracks. For a more rational use of the feeding territory bears walk in shuttle-manner, the center line of which is the course of the creek or animal tracks. Usually the animal moves parallel to the direction of the watercourse. In areas with high concentrations of preferred plants, such as butterbur, bears can remain until they crop all the plants. When grazing on herbaceous vegetation bears can be distracted from their main activity eating insects found in the grass and mollusks.
Brown bears eat up underground parts of grassland plants such as tubers of Arisaema amurense and Lilium distichum. The animals pry the bulbs with their claws pulling them to the surface, then bite them off the stem and eat. At the site of such dig an almost invisible hole remains next to the aerial part of the plant. When procuring the roots of Hedysarum branthii animals make more notable excavations.
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Tiger
Apr 3, 2022 1:47:46 GMT -5
Post by brobear on Apr 3, 2022 1:47:46 GMT -5
Behavior of Brown Bears During Feeding in the Sikhote-Alin - continued: Brown bears feed on berries by two basic ways: devour them from the plants or pick up fallen berries from the forest cover. The first way is more common. When feeding on berries of short-growing plants animals graze with their heads down to the ground picking berries in one or several pieces at once with their lips, depending on the density of berries on a plant. In this manner, the bears can for a long time eat red berry (Rhodococcum vitis-idaea) and blueberry (Vaccinium uliginosum) — the berries that are important for their diet. Tearing berries off medium sized shrubs (blue-berried honeysuckle — Lonicera spp., currant — Ribes spp., raspberry — Rubus spp., spiny eleutherococcus — Eleutherococcus senticosus) bears raise their heads to the branches, or if necessary, stand up on their hind legs. In this manner, feeding on honeysuckle (Lonicera edulis), the bear moves from one bush to another, tearing them one by one. At this the animal bows, crushes, and sometimes breaks the branches, going through them with its paws. When feeding on the fruits of the vines (kolomikta actinidia — Actinidia kolomikta, tara vine — Actinidia arguta, Amur grape — Vitis amurensis, Chinese magnolia vine — Schisandra chinensis) bears grab the vine and shake it trying to drag it down from the support tree. Some fruit falls down to the forest cover and the bears pick them up. Soft fruits growing on trees (apple — Malus spp., Dahurian buckthorn — Rhamnus davurica, pear — Pyrus ussuriensis, bird cherry — Padus spp., hawthorn — Crataegus spp.) are almost inaccessible for brown bears due to the fact that the majority of adult animals are unable to climb trees. The animals bend the branches and eat up the fruit that they can reach or settle with fallen berries. Brown bears feed on berries of common bird cherry (Padus avium) more often than on fruit from other trees because bird cherry trunks often grow at a sharp angle to the surface which allows the animals to reach fruiting branches while standing.
The bears eat up berries and other soft fruit that fall from the trees, shrubs and vines by circling around fruiting trees. In this manner they pick up the fruits of Amur grape, actinidia, wild roses (Rosa spp.), honeysuckle, and spiny eleutherococcus.
Brown bears are more likely to visit berry beds with the most plentiful fruitage compared to neighboring berry beds (Mikhailovsky and Skryabina, 1972). If animals are not disturbed they repeatedly visit areas with the abundance of berries eating up a significant portion of the fruitage. Within two months (July, August) brown bears ate 43% of biological fruitage at a relatively large area in sedge blueberry bed. In a single feeding a bear ate up around 8 kg of blueberry, and in total the bears consumed approximately 7% of biological fruitage of the entire area of studied blueberry beds (Mikhailovsky and Skryabina, 1972). In some seasons berries can be a background component of the diet of bears. Thus, cranberries constituted 97% of the diet of brown bears in the vicinity of the Sikhote-Alin Nature Reserve in the second half of August–September 1999. Animals come to berry beds long before the ripening of cranberries. As soon as the berry turns red the bears begin to eat it.
The nutritional value of berries is inferior to other fattening feed. In addition, thick-skinned berries, such as cranberries, are poorly crushed in the jaws of animals, and most of them remain intact passing through the digestive tract. Ripe berries are always better digested than underripe ones, especially bird cherry. The bears chew soft fruits of actinides, grapes, and wild rose, while blueberries are crushed at swallowing (Yudin, 1993).
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Tiger
Apr 3, 2022 1:49:31 GMT -5
Post by brobear on Apr 3, 2022 1:49:31 GMT -5
Behavior of Brown Bears During Feeding in the Sikhote-Alin - continued: Nuts and acorns are the most important caloric and fattening feed of brown bears in Sikhote-Alin (Bromlei, 1965, Yudin, 1993, Seryodkin et al., 2012). Nuts of Korean pine (Pinus koraiensis) are paramount for the diet of bears.
Unlike Asiatic black bears (Ursus thibetanus) brown bears rarely procure pine cones by climbing into the crowns of trees. However, such cases are known. Females and juveniles are more adapted to climbing trees. E.N. Smirnov (Sikhote-Alin Nature Reserve, personal communication) observed an adult brown bear female in the crown of a pine tree breaking off branches with cones and throwing them down to the forest cover where her cubs awaited.
Fallen cones are very important for the bears. When there are not many cones the animals consume each cone where they find it, and then proceed to another one. With the abundance of fallen cones the animals may rake them in heaps (up to 50 pieces) and then pick the nuts out of the cones at their leisure. During the snow season (spring or late autumn) bears can dig up cones from under the snow leaving snow trenches or muzzle marks.
The ways brown bears procure nuts from the cones are different depending primarily on the ripeness of the cones. The animals bite open the least ripe, still strong and green cones, with sticky covering skin. They can tear off some parts of the skin from the green cones, and then pick the nuts. When dealing with more ripe cones bears tear off the skin only at the bottom and open the upper part with their paws or muzzles; they pick the nuts between the open cone skin. Instead of peeling ripe, dry cones, they crush them. Sometimes bears break cones in half along the axis or in several parts. Cones become soft after rain and can be peeled easily. The bears may try to peel some cones, but after finding bad nuts they move on to other cones. The remains of cones eaten by brown bears are similar to those of Asiatic black bears and, to a lesser degree, of wild boar (Sus scrofa). In spring bears prefer to dig up the cones out of the snow, rather than consuming newly fallen cones. This may be because it is easier to procure nuts out of wet cones that were under the snow, than from dry, newly fallen ones.
When feeding on the nuts of dwarf pine (Pinus pumila) the bear bites and breaks branches and trunks of trees, and then eats the cones. The animal chews unripe cones completely. It browses ripe cones eating the nuts together with nutshells. The central axis with extending skin remains intact (Fig. 2). The bear picks up nuts of Manchurian hazel (Corylus mandshurica) and hazel (Corylus heterophylla) from the forest cover or breaks the bushes with the fruit. Brown bears collect Manchurian walnuts (Juglans mandshurica) only from the forest cover. While doing so they trample the grass under the trees racking the nuts in piles with their claws. After that they lie down on the ground, grab the nuts collected with one of the forepaws and eat them all in a row together with thick nutshell, cracking them with their teeth (Bromlei, 1965). Acorns of Mongolian oak (Quercus mongolica) in the crowns of trees are almost inaccessible to brown bears. Before the acorns begin to fall down the bears may look for thin scrubby fruit-bearing oak trees. These trees grow on the ridges, in places exposed to frequent winds. The animals are able to break thin trees standing on hind legs. 9 Mongolian oaks damaged this way were found in the basin of Dzhigitovka River (Terney district) over 50 m of the route. The diameter of the trees was 5.4–7.6 cm. Three oaks had their trunks broken at a height of 100 cm, and six trees had broken branches (50–180 cm above the ground). The bear bit the branch and then pulled it down, some branches it broke without biting.
Since the beginning of acorn fall brown bears feed on acorns collecting them from the forest cover. For clarity, we will describe 4 stages of usage of this food resource by brown bears in the basin of Kunaleyka River (Sikhote-Alin Nature Reserve) in 1999. The time frame provided varies depending on the year and region, but generally reflects the sequence of phases of acorn consumption at uneven fruitage. 1. August 28th–September 3rd — acorns have not yet reached their full size and not ripened enough; they are consumed by Asiatic black bears in the crowns of the trees. They are still inaccessible to brown bears.
2. September 5th–15th — the acorns ripen and begin to fall. The population density of brown bears in oak forests increases steadily with the local fruitage. The bears actively feed on fallen acorns.
3. September 15th–25th — full ripening and abundant falling of acorns. This period was characterized by the most intensive consumption of acorns by brown bears and their highest numbers in the river basin.
4. September 25th–30th — very few acorns remain in the trees and on the forest cover. Bears actively migrate from the oak forests.
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Tiger
Apr 3, 2022 1:50:29 GMT -5
Post by brobear on Apr 3, 2022 1:50:29 GMT -5
Behavior of Brown Bears During Feeding in the Sikhote-Alin - continued: The behavior of bears grazing in oak forests has certain characteristics. The animals look for fallen acorns in the forest cover and eat them. They pick acorns from the cups with their lips, separating the kernel from the shell in their mouths. When chewing the acorns the shell is pushed to the corners of the mouth and falls down from both sides of the mouth. In addition, acorns can be chewed and swallowed together with the shell. Plowing through the leaf litter with its muzzle the animal often leaves behind tracks similar to those left behind by feeding boars. When moving, the bear circles around acorn-bearing oaks or moves in a straight line at an average speed of about 2 m/min. The animal keeps its muzzle to the ground, sometimes lifting it to listen and look around. With abundant fruitage of acorn some bears can feed for a long time in a small area of the forest without leaving it. By radiotelemetry it was revealed that a brown bear female with cubs was feeding for seven days in September at an area of 0.2 km2 (Seryodkin et al., 2012).
Bears are able to procure acorns from under the snow layer. After tracking for three months a bear that hasn't settled in its lair Kostoglod described the attempt to procure acorns from under snow cover 40 cm high. At a distance of 120 m in the oak stand this bear moving in shuttle-like manner with the search width of 30–40 m has made over 30 stops. At each stop it sank its nose repeatedly into the snow for 7–10 cm, leaving a semicircle of holes (up to 15–20 holes). In some places the snow was dug up to the forest floor where the animal probably could find and eat isolated acorns (Kostoglod, 1981). The availability and the quantity of fattening feed affect the food relation of bears towards it. With a large number of pine nuts or acorns the animals manifest fastidiousness in feed and irrationality of its use. The bears bite open the nuts of Korean pine and dwarf pine and pick the seeds leaving the shell behind, so that some nuts are left in the cones. The animals choose the most ripe and large acorns picking them not very carefully from the forest cover, so that a large amount of acorns remain at the feeding site; the solid acorn shell is not consumed. In case of feed shortage caused by poor fruitage another peculiarity is observed in the beginning and the end of fattening: the bear tries to eat up all nuts and acorns, even bad ones, along with the shells. Wasteful attitude towards the feed during its abundance is true not only in respect to plant feed. For example, during mass spawning of salmon on Kamchatka brown bears do not eat up fish completely giving preference to its skin and hard roe (Revenko, 1993).
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Tiger
Apr 3, 2022 1:51:18 GMT -5
Post by brobear on Apr 3, 2022 1:51:18 GMT -5
Behavior of Brown Bears During Feeding in the Sikhote-Alin - continued: During the period of intensive fluctuation of birch sap from March to May brown bears tap the trees and lick the sap from bruises. The bear bites the trunks and rips the bark off in cross direction. The result is a horizontal bruise up to 35 cm wide and 15 cm high (Fig. 3). The animal taps birches at the height of 20 to 130 cm, usually at 40–60 cm from the ground. Sometimes an animal makes several tappings at different sides and different heights. Often one bear damages several adjacent birches in turns and drinks sap from them. Asiatic bears damage the trees in similar manner (Seryodkin, 2003). The trees bled by bears are more common in the upper reaches of streams where the lairs of brown bear are located. Three species of birch grow in such places in Sikhote-Alin: Asian white birch (Betula platyphylla), Yellow birch (Betula costata) and rockbirch (Betula lanata). These species are subject to tapping by brown bears. Bears begin to feed on birch sap right after they exit their lairs. Bromlei suggested that animals use birch sap as a purgative (Bromlei, 1965). Possibly, the sap also serves as the source of glucose, fructose, salts and microelements.
Presumably, actinidia vines are also used for the normalization of the digestive tract after the winter sleep. V.A. Solomatin (Sikhote-Alin Nature Reserve, personal communication) observed dedicated feeding of brown bear on A. kolomikta in Yasnaya River basin in March. The animal bit off and consumed the stems of vines moving along the thick of vegetation.
During spring and summer brown bears in Sikhote-Alin rip the bark off pine trees (Khingan fir — Abies nephrolepis, Korean pine and larch — Larix cajanderi) and eat bare cambium. Feeding on cambium is less specific for brown bears than for Asiatic black bears (Seryodkin and Pimenova, 2002).
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Tiger
Apr 3, 2022 1:52:54 GMT -5
Post by brobear on Apr 3, 2022 1:52:54 GMT -5
Behavior of Brown Bears During Feeding in the Sikhote-Alin - continued: Brown bears dig out burrows of chipmunks (Tamias sibiricus), mouse-like rodents (Clethrionomys spp., Apodemus spp.), badgers (Meles meles), raccoon dogs (Nyctereutes procyonoides), and nests of wasps (Vespinae). They seek them out using their sense of smell and hearing.
Chipmunk burrows (Fig. 4) are unearthed for the purpose of consuming the hoards of nuts or acorns. Apparently, sometimes a bear manages to catch and eat a chipmunk itself or its brood. The animals are actively searching for and consuming hoards in autumn, rarely in spring and winter before settling in lairs (Bromlei, 1965, Telegin, 1980, Kostoglod, 1981, Sobansky, 1981, Pikunov, 1987, Smirnov and Shurygin, 1991). We know of a case when the animals were actively digging out chipmunks' hoards containing pine nuts in August. This was due to the fact that only by that time pine nuts from last year's abundant fruitage have come to an end, and chipmunks had time until August to fill their hoards. Bears unearth burrows of chipmunks both in starving time, and in periods with abundance of fattening feed. However, the number of such dig sites significantly increases with the shortage of nuts and acorns. For example, in autumn of 2005 Korean pine nuts from the hoards of chipmunks were essential in fattening of brown bear in Terney region of Primorsky Krai. It was due to the fact that pine nuts were generally consumed by squirrels (Sciurus vulgaris) which could pick cones from the trees and chipmunks which were high in number. Brown bears could not climb trees, so they had to consume hoards made by chipmunks. A bear finds chipmunk burrows guided by its sense of smell. V.A. Solomatin observed a bear in the Sikhote-Alin Nature Reserve stops short, sniffs the ground in the radius of 2–3 m, and then digs the hoard of a rodent. The animal digs with its front paws turning towards the hole. It bites through the roots of trees and shrubs that get in its way. The animal rakes the soil under itself making a heap of earth and rocks. A bear can turn over rocks weighing over 50 kg. If a bear is digging on the slope, it stands with its muzzle turned uphill, raking the sole downwards. Measurements of 40 dig sites revealed the following results: the width of the pit — 40–155 cm (101 cm on average), the length of the pit — 30–217 cm (84 cm on average), and the depth of the pit — 24–100 cm (55 cm on average). Sometimes there's a deepening about 30 cm wide and up to 50 cm deep at the bottom of the pit. This deepening corresponds to the size of the bear's paw, and it is formed when the bear removes the contents of the hoard with one paw. A heap at a dig site is up to 3 m long, it contains from 0.04 to 3.6 m3 of soil (0.7 m3 on average) and can be located not only on one side of the pit, but around the entire pit as well. A bear can stop digging a pit if it stumbles upon an obstacle and resume digging nearby where the soil is softer. Most often animals dig chipmunk's burrows on the slopes of varying steepness and exposures, more rarely – on the terraces, even more rarely – in flood plains and on ridges. The largest number of dig sites (90%) that we encountered was located in pine–broad-leaf forests. Up to 10 active sites of chipmunk burrows dug out by bears were counted by Kostoglod in pine forests along Serebryanka and Dzhigitovka rivers per 1 km of route (Kostoglod, 1981). During one day's course a brown bear usually unearths 1–2, rarely three hoards in conditions of average population of chipmunks and bountiful fruitage. With average and a poor pine fruitage the stock of nuts in chipmunks' hoards is smaller in number, so a bear may need to unearth up to 5–6 hoards a day (Pikunov, 1987). Up to 20 kg of stored feed may be found in a chipmunk's hoard (Oshmarin and Pikunov, 1990).
The animals dig out nests of wasps in the summer and spring. Bears eat up the eggs and larvae of insects. Dig sites of nests are inferior in size to dig sites of chipmunks' hoards. Normally their size does not exceed 70 cm in diameter and 35 cm in depth. Bears can spend a lot of time searching for wasp nests in the summer. In areas with a relatively high number of bears over ten freshly dug out nests per 0.5 ha can be found. When digging out burrows of mouse-like rodents a bear digs trenches or turns over pieces of turf. The largest pits are dug by bears when they dig out the burrows of badgers hoping to catch these animals. In some cases they succeed. Bears dig deep pits pulling out thick trees and turning over large rocks. I.G. Nikolaev (private message) during tracking of a male brown bear in Pogranichniy Region of Primorsky Krai in November found a network of badger burrows dug out by it. The width of the trench corresponded to the width of the bear, and the height reached 160 cm. The bear was engaged in excavation for two days, but in that case it couldn't procure the badger. In another case, a bear procured and ate a badger after digging its temporary shelter in the basin of Chaschevity creek (Sikhote-Alin Nature Reserve) in late October. The dimensions of the pit: 180 × 150 × 75 cm; when digging the animal pulled from the ground and threw away a rock with dimensions of 60 × 50 × 40 cm.
Bear excavations are clearly visible in the forest and they stay untouched for many years. In places of the permanent habitat of brown bears excavations of different time ranges may be found on some hills every tens of meters. In such cases, one can state the impact of brown bears on the micro-relief and vegetation of forest slopes.
The manner of digging out burrows and nests by brown bear is different from that of the Asiatic black bear. Brown bear digs wider pits, pulling over the roots of trees and shrubs, removing fallen trees and rocks. Asiatic black bear digs a smaller funnel-type pit (Pikunov, 1987). In addition, the nests of wasps are unearthed by badgers. Their excavations look even smaller than those of Asiatic black bears.
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Tiger
Apr 3, 2022 1:54:22 GMT -5
Post by brobear on Apr 3, 2022 1:54:22 GMT -5
Behavior of Brown Bears During Feeding in the Sikhote-Alin - continued: Biting through the wood brown bears procure wood insects, social hymenopterans, small mammals, and Asiatic black bears.
Most often one can encounter marks on the trunks of live or dry, but not yet fallen trees formed as a result of procuring nests of bees (Apis cerana) and bumble bees (Bombus spp.) by bears. Having reached the nest the animals eat honey stored by insects, their eggs and larvae. Similar marks are formed when the animal tries to procure chipmunks or flying squirrels (Pteromys volans) hidden in hollows of tree trunks, and nests of birds living in tree hollows. The damages done to trees by two species of bears are hardly different from each other. Usually nests and hollows are found in trees with hollow core, and the bear needs to bite through the wood layer to reach the hollow. If a tree is bent, the animal usually bites it from the obtuse angle formed with the ground and less often from the acute angle, generally if the timber is less thick at that side. Out of the 34 marks described 22 were located on living trees and 12 — on dried-up ones. In 91% of cases the bears bite through the wood of coniferous trees: larch — L. cajanderi (n = 1), Ajan spruce — Picea ajanensis (n = 7), Korean pine (n = 9), and most often, the softest coniferous species — Khingan fir (n = 10). Most of the trees were located in pine–broadleaved and dark coniferous forests. Yellow birch, aspen (Populus tremula), and Japanese elm (Ulmus japonica) each had one mark as well. The average diameter (at chest level) of damaged trees was 32 cm (from 16 to 83 cm). The part of the tree damaged by bear has a bit-through hole and damaged surface around it with the bark and the upper layer of wood ripped off. The lower level of damage is located at a height of 0 to 150 cm (42 cm on average), and the upper level reaches 285 cm (148 cm on average) above the ground. The bit-through hole is usually of vertically elongated shape with a width of 5–25 cm (11 cm on average) and a height of 13–120 cm (44 cm on average). To achieve the desired result a bear, according to our observations, bites through up to 24 cm thick wood.
Ripping off the bark and biting through the wood of living, dried-up or windfallen trees, bears procure the larvae of bark beetles (Scolytidae), longhorn beetles (Cerambycidae) and other xylophage insects. The animals ravage ant-hills at the bottoms of dead trees or in rotten deadwood eating adult insects, larvae and eggs. Bears break rotten deadwood and stump into splinters in search of ants. Most often, dry trees with marks and deadwood broken by bears are found at old burned areas, where there are many dead trees with insects living inside. There are cases when brown bears were trying to reach Asiatic black bears that chose hollows at the bottom of trees as their lairs. Brown bear bites and scratches the basis of a tree trying to widen existing holes. For example, in 2000 a brown bear widened the hole in the basis of a poplar in the Sikhote-Alin Nature Reserve until it was able to push its way into the lair of an Asiatic black bear.
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Tiger
Apr 3, 2022 1:54:55 GMT -5
Post by brobear on Apr 3, 2022 1:54:55 GMT -5
Behavior of Brown Bears During Feeding in the Sikhote-Alin - continued: In the summer, before the start of fattening, brown bears spend much time searching for invertebrates. In the period of feeding on herbaceous vegetation invertebrates introduce diversity into the vegetarian diet.
Often bears seek out and ravage ant-hills. This is characteristic of brown bears in different regions (Yurgenson, 1937, Kucherenko, 1983, Chernyavsky and Petrichenko, 1984, Vyrypaev, 1984, Pazhetnov, 1990, Loskutov and Radchenko, 1991, Mordosov et al., 1993, Swenson et al., 1999, Mattson, 2001). A bear finds ant-hills using its sense of smell, sometimes at a distance of a few tens of meters (Rukovsky and Kupriyanov, 1970). After finding an ant-hill the bear removes its upper layer (the outer mound) with its paw, revealing the nest chamber, eats away its contents, and sometimes brutally destroys the entire ant-hill (Pazhetnov, 1990). In Lapland Reserve bears destroy up to 40% of ant nests in their feeding area (Nasimovich and Semyonov-Tyan-Shansky, 1951). The animals may completely eat away this feeding component (ants) on a certain territory (Pazhetnov, 1990). Some ant-hills ruined by bears are reconstructed by the insects, while others cannot be restored.
In search of insects and earthworms bears often turn over rocks and fallen trees (Bromlei, 1965, Yudin, 1993). In Sikhote-Alin similar traces of life activities are often found in mountain ranges along bear trails. E.P. Krasnikova in August of 1973 observed a bear turn over stones in the channel of Serebryanka River to collect caddis worm — Trichoptera (records of the Sikhote-Alin Nature Reserve).
About 10 places were found in scattered stones in Cheryomukhovaya river-valley (Dalnegorsk region) where brown bear, apparently, was trying to catch lizards (Amur grass lizards), that were warming themselves in the sun. The animal threw away the stones under which the reptiles were hiding, leaving pits among the stones.
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Tiger
Apr 3, 2022 1:55:37 GMT -5
Post by brobear on Apr 3, 2022 1:55:37 GMT -5
Behavior of Brown Bears During Feeding in the Sikhote-Alin - continued: Predation on the ungulates is a trait of ecology of brown bears typical for different areas of the species range (Bromlei, 1965, Semyonov-Tyan-Shansky, 1979, Zavatsky, 1979, Lavov, 1987, Pazhetnov, 1990, Bobyr, 1991). The extent and nature of predation vary with the seasons. In most cases, this method of feeding behavior is of the greatest importance for bears in the spring (Pazhetnov, 1990). This statement is typical for brown bears in Sikhote-Alin (Bromlei, 1965, Yudakov and Nikolaev, 1987, Yudin, 1993, Kostoglod, 2006). In summer there is a decline of predation related to the abundance of feed (Bromlei, 1965). In autumn with the abundance of fattening feed of vegetable origin predation is not expressed, but during hungry years it is on the contrary typically occurring among bears (Bromlei, 1965, Rakov, 1966, Abramov, 1972). Wild boar and red deer (Cervus elaphus) are the most common ungulate prey of brown bears in Sikhote-Alin.
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Tiger
Apr 3, 2022 1:56:28 GMT -5
Post by brobear on Apr 3, 2022 1:56:28 GMT -5
Behavior of Brown Bears During Feeding in the Sikhote-Alin - continued: Brown bears are commonly consuming dead animals found by them (Zavatsky, 1979, Zyryanov, 1979, Kaletskaya, 1981, Zhiryakov, 1987, Pazhetnov, 1990), including in Sikhote-Alin (Bromlei, 1965, Matyushkin, 1974, Darman, 1982, Yudin, 1993, Zaitsev and Seryodkin, 2011). The results of the capture of bears conducted by us in the Sikhote-Alin Nature Reserve have shown that they are attracted to carrion (Seryodkin et al., 2005b). In 1992–2001 six brown bears were caught with the use of bait: three animals using meat bait and three — using fish bait. The rate of successful capture was much higher using these baits (560 days/individual), rather than using trails and marked trees (1196 days/individual). Meat baits are consumed by the animals in any season. Besides dead and wounded animals bears eat the prey of other predators and the remnants of their meals in Sikhote-Alin. Most often, the bears consume prey of tigers and lynxes (Matyushkin, 1974, Kostoglod, 1976, Seryodkin et al., 2005a). A case of using the prey of yellow-throated marten is known (Zaitsev, 1991). Large bears cannot only eat up remains after tigers, but also chase them off their prey or join the fight (Sysoev, 1966, Kucherenko, 1971, Kostoglod, 1976, Seryodkin et al., 2005a). In the snow period some bears purposely track tigers and lynxes to find the remains or take away their prey (Kostoglod, 1976, Seryodkin et al., 2012). According to observations of Kostoglod, the trail of a bear not settled in its lair tracking other predators in order to capture their prey was 22% of the total length of the bear trail (44 km out of 200 km) (Kostoglod, 1976). In the spring before snow melting bears look for animals which died during winter and prey of tigers buried in snow (Seryodkin et al., 2005a). For this purpose bears go along the floodplain of a river or a creek, often leaving the path to examine interesting places, winding, sometimes stopping to sniff. A bear is able to smell the odor of the remains of an animal at a distance of 250 m at a temperature below 0 °C. Bears also go in the footsteps of their relatives, picking uneaten remains of carrion. Snowtracking of three brown bears in the basin of a creek in the Sikhote-Alin Nature Reserve in April revealed that along the 17 km trail the bears have four times found the remains of red deer crushed by tigers during the winter, and once — a whole red deer that died of a broken limb. In three cases other bears have been on these tiger prey before them.
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Tiger
Apr 3, 2022 1:58:29 GMT -5
Post by brobear on Apr 3, 2022 1:58:29 GMT -5
Behavior of Brown Bears During Feeding in the Sikhote-Alin - continued: Covering the prey with soil, forest cover, branches and other forest products is typical, but not necessary for brown bears in Sikhote-Alin (Matyushkin, 1974). The burial of the prey may be complete when the whole animal is hidden, or partial. Apparently, the act of covering primarily provides saving the prey from spongers, as the bear's prey attracts corvid birds, and the predator guards it from them (Pazhetnov, 1990). On the Kola Peninsula, burying of the remnants allows to distinguish the bear's prey from accidental carrion (Semyonov-Tyan-Shansky, 1972). For the Sikhote-Alin this assumption is not true. Out of 28 known cases of brown bears feeding on dead bodies of animals in 8 cases (28.6%) the burial occurred. Four times out of five bears were burying their prey, twice — the prey of tigers (out of 20), in both cases the tigers were chased off by the bears, and twice the bears buried dead wounded animals found by them. It is clear from these data that the bears are more likely to bury whole carcasses of animals rather than their remains left after other predators. A brown bear may cover its prey after he had already started to eat it (Matyushkin, 1974), or after burying the carcass, may wait for some time without eating it. In the latter case, covering the prey with the forest cover by maintaining the temperature contributes to faster fermentation processes that make fresh meat “ripe” that is more attractive for animals (Korytin, 1998). We know of two cases when brown bears buried dead animals, but did not eat them at once. In the first case, a bear buried a dead wounded boar and returned to the place of burial on the third day. In another case, a brown bear that killed another brown bear covered it with forest cover and left the place without touching the food. For covering a red dear one of predators had to dig up and bring to the center the soil and forest cover from an area of 60 m2. The author also observed Kamchatka brown bears waiting for “ripening” of dead prey. A large male bear began to eat a buried female bear three days after procuring it at Kronotskaya River (Kronotsky Reserve) in September 2003.
Burial instinct can be observed at one-time feeding on small prey immediately after it is procured or discovered. For example, a bear was spotted in Kamchatka which was feeding on kalan (Enhydra lutris) for 40 min and during that time it would periodically tear down shrubbery and cover the prey with it using its fore paws.
When a brown bear finds carrion or prey of another predator it often drags it away, typically within 50 m. Sometimes the predator moves separate pieces of prey over long distances where it eats them. A bear can also drag its prey to another location with better protective properties. Moving prey is seen as a manifestation of concern for protection of prey (Pazhetnov, 1990). On the first day of eating meat bears usually suffer from indigestion and their excrements are of liquid consistency. Already on the second day gastrointestinal tract is usually back to normal (Kostoglod, 1981). In the spring of 2001 a male brown bear found a whole carcass of red deer in the Sikhote-Alin Nature Reserve and ate about 50 kg of meat on the first day; the predator didn't get indigestion, probably because before that he had eaten the remnants of another red deer. A bear lives near the carcass of a large ungulate from 3 to 10 days. A bear eats a red deer weighing 150 kg completely in 5–6 days (Kostoglod, 1981).
In the first place a bear eats meat from croup and proximal parts of hindlegs of an animal, as well as internal organs. The bear does not touch the contents of the stomach and intestines of the ungulate. Then the bear eats meat from other parts of the body; after finishing with the meat it eats the skin, distal parts of limbs, head and small bones. It eats soft antlers of ungulates completely and bites off tips of hard antlers. In the valley of Serebryanka River in April 1983 V.A. Palkin found a female red deer killed and covered by a bear; the predator has only eaten the embryo from the red deer (from the archive of the Sikhote-Alin Nature Reserve). Usually a bear leaves behind partially consumed limb bones of large animals, upper and lower jaws, and parts of the spinal bone; sometimes pelvic bones, shoulder bones and ribs. With a shortage of feed (in winter and early spring) bear consumes carcasses to a greater extent. A bear that has not fallen into winter sleep fully utilizes animals, including all the bones (Kostoglod, 1976). The smaller the animal eaten by the bear, the better it is utilized. For example, a brown bear ate a musk deer in summer, leaving behind only the lower jaw, two cuspid teeth of the upper jaw and a few small fragments of shattered limb bones.
Usually the bones that a bear eats are not digested and remain intact. In two places in the Sikhote-Alin Nature Reserve we found excrement of a brown bear containing homogeneous white mass with minor inclusions of wool of ungulates. They were dated to the end of March. Chemical analysis of the samples showed that these were digested bone remains, with domination of calcium oxide (31.2%) and phosphorus (21.6%). These substances could be formed in the intestines of the animal in an alkaline medium by restoring the phosphate salts formed in turn by dissociation of bone substance in the acidic environment of the stomach. Dissolution of the bones of mammals in the stomach is possible only when a bear is feeding on bones exclusively, without other food components (e.g., meat) diluting the stomach acid. This is possible when a bear finds bone remains after it leaves its lair, when the lack of feed forces it to be omnivorous. This assumption is confirmed by the fact that one of the above samples was found close to an almost bare wild boar skeleton that was eaten by a bear. It is also possible that the bones were eaten by bears not in spring, but before hibernation in lair, and the conversion of bone substance was occurring during the winter. While eating the prey a bear usually lives in close proximity to it, but sometimes it stays near it for a short time and, having utilized a small part of the carcass, leaves the place. The bear sets up its beds (one or more) close to the prey, sometimes directly near it. Parts of skeletons are often found near the beds, because a bear often feeds when lying in bed. The area of the active movement of a bear around the prey while feeding on it does not usually exceed 500 m2, here one can find remnants of the prey, beds and excrement of the predator. Often bears break and bite the trees, shrubs and branches close to the prey. From the prey the animals go to watering creating a footworn path. In winter, bears can be satisfied with the snow (Kostoglod, 1976).
Brown bears can be aggressive towards the predators (other bears, tigers) and people approaching their prey or carrion.
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