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Tiger
Apr 5, 2022 9:48:39 GMT -5
Post by brobear on Apr 5, 2022 9:48:39 GMT -5
Species composition of tiger diet bioone.org/journals/wildlife-biology/volume-2019/issue-1/wlb.00508/Prey-selection-of-Amur-tigers-in-relation-to-the-spatiotemporal/10.2981/wlb.00508.full This study reports the critical prey resources for the recovery of this small population of tigers in China. Our camera traps recorded 11 tigers during the study period. All scats used in this study came from at least 9 tiger individuals, indicating that majority (82%) of HNR tigers detected using camera traps contributed to the scat samples but with high heterogeneity in the number of scats of each tiger (mean = 0.6, SD = 9.2). At the population level, tigers are known to be selective predators. Our results are in accordance with previous findings regarding the diet of tigers across their range, which indicate that medium to large wild ungulates formed the majority of the tiger diet (Karanth and Sunquist 1995, Sugimoto et al. 2016). Wild boar, sika deer and roe deer contribute up to >90% of the total biomass consumed (Table 1), illustrating that they are currently key prey for this small tiger population across the Sino–Russia border. However, our results differed from those of Miquelle et al. (2010) in the Russian Far East in that red deer (200 kg) were another very important prey item. To more deeply explore the Amur tiger dietary requirements and differences in winter, we compared our results with those from a study by Kerley et al. (2015) implemented at three sites in Russia. We had only 6 prey species compared to 9 or 10 at 3 other sites (Supplementary material Appendix 1 Table A1) (Kerley et al. 2015). The lower diversity at our site during winter reflects the absence of several prey species found elsewhere and also may be a consequence of our smaller sample size and lower study duration. Sika deer have largely replaced red deer as the most common cervid in HNR, China and adjacent SW, Russia. Kerley et al.'s other two sites were areas where the prey base included red deer that are not found in HNR and SW, Russia (Supplementary material Appendix 1 Table A1). As reported by Griffiths (1975), tigers are also ‘energy maximizers’ and in our study with the two largest ungulates, wild boar and sika deer, contributed >80% of the total biomass consumed by tigers (Table 1). However, compared with wild boar, sika deer were consumed to a lesser extent by tigers, even though they had the highest abundance among the ungulates. This result is partially attributable to the difference in this two prey's vulnerability and other factors. Small prey species (e.g. badgers) were occasionally preyed upon, reflecting the avoidance of smaller prey by tigers (Karanth and Sunquist 1995, Sugimoto et al. 2016).
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Tiger
Apr 5, 2022 9:51:04 GMT -5
Post by brobear on Apr 5, 2022 9:51:04 GMT -5
Table 3. Spatial and temporal overlap (95% confidence interval) between tigers and their main prey in Hunchun Nature Reserve, northeast China.
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Tiger
Apr 5, 2022 9:52:15 GMT -5
Post by brobear on Apr 5, 2022 9:52:15 GMT -5
Cattle were identified in the tiger diet in winter, but represents a relatively low contribution to their diet (2.88% of the total biomass consumed). The overall biomass contribution of cattle may be underestimated, because almost all cattle were brought back to the villages from the forest in winter. Predation on cattle has been associated with easy access linked with poor livestock husbandry practices (Wang et al. 2016, 2017); more than 30% of the HNR and its surrounding area is grazed by unattended domestic livestock at an average stocking rate of 8–12 cattle km–2 in summer. Tigers frequently prey on cattle, suggesting that cattle have become a regular food source for this border population. However, this behaviour has resulted in substantial human-tiger conflict, as reported by Wang et al. (2016, 2017) and Soh et al. (2014), who reported that more than 370 cattle depredations occurred between 2008 and 2014. A similar pattern was found in a different national park in India, where livestock accounted for 6 to 12% of the tiger diet despite the park's high wild prey densities (Biswas and Sankar 2002, Bagchi et al. 2003, Reddy et al. 2004). Table 4. The parameter estimates, standard error (SE), z-value and p-value from the occupancy model for the Amur tiger in northeast China. Estimates of beta coefficients are reported for standardized covariates, scaled to mean and standard deviation. All of the reported estimates of coefficients that marked in bold are significant (p<0.05).
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Tiger
Apr 5, 2022 9:53:53 GMT -5
Post by brobear on Apr 5, 2022 9:53:53 GMT -5
Prey abundance and selection bioone.org/journals/wildlife-biology/volume-2019/issue-1/wlb.00508/Prey-selection-of-Amur-tigers-in-relation-to-the-spatiotemporal/10.2981/wlb.00508.full The body size, availability and vulnerability of prey are the primary factors determining prey selection. A recent meta-analysis (Hayward et al. 2012) suggests that species weighing between 60 and 250 kg are preferred by tigers, and in our study the two large prey, wild boar (103 kg) and sika deer (95 kg) were the preferred prey. The wild boar is the largest ungulate preferred by Amur tigers (Fig. 3), supporting the findings of Hayward et al. (2012); they report that the wild boar is one of the species most preferred by tigers based on selectivity index scores from 3187 kills or scats from 32 prey species. Our results are also congruent with those of earlier studies from reserves in Russia (Kerley and Borisenko 2007, Kerley et al. 2015, Sugimoto et al. 2016). The strong preference for wild boar may reflect its behaviour, especially when in groups, of noisily foraging, head down in the leaf litter making it much easier to approach. Groups of wild boar are likely slower when attempting to escape when the ground is covered with snow in winter (Miquelle et al. 2010). Easy to locate and prey wild boar may explain their preferred status by tigers. Previous study also showed that individual vigilance decreased with increasing group size when wild board were feeding (Quenette and Gerard 1992). Sika deer are the second most dominant prey species of tigers at our study site, and tigers showed a neutral preference toward this species. Sika deer may be killed less frequently than expected based on their relative abundance within three ungulate prey. However, we believe high abundance of sika deer in our study area makes them a key prey resource. Furthermore, large sized deer generally represent a dominant proportion of a tiger's prey biomass requirement in most parts of its range (Biswas and Sankar 2002, Hayward et al. 2012). Our results differed from those of Kerley et al. (2015) and Sugimoto et al. (2016) in adjoining SW Russia, where tigers selected against sika deer (D<–0.65). Preference differences may reflect differences in species specific hunting success among sites. For example, snow depth and terrain differences may explain the differences in preference. Further research is needed to better understand how the probability of encounter and hunting success contribute to prey preference. The relative abundance index has become a common approach to measure prey available in the study of animal diet (Weckel et al. 2006, Henschel et al. 2011). But this index is highly biased by a suite of factors (e.g. species ecology, imperfect detection and study design) (Sollmann et al. 2013), we used prey abundance estimated from N-mixture models, which accounted for imperfect detection of individuals, to determine the relative availability of major prey.
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Tiger
Apr 5, 2022 9:56:33 GMT -5
Post by brobear on Apr 5, 2022 9:56:33 GMT -5
Table 5. Activity periods of the Amur tiger and its main prey based on the number of independent detections (n) recorded by the camera traps in Hunchun Nature Reserve, China, during November 2014–April 2015.
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Tiger
Apr 5, 2022 9:58:20 GMT -5
Post by brobear on Apr 5, 2022 9:58:20 GMT -5
Spatiotemporal overlap between the tiger and its main prey species bioone.org/journals/wildlife-biology/volume-2019/issue-1/wlb.00508/Prey-selection-of-Amur-tigers-in-relation-to-the-spatiotemporal/10.2981/wlb.00508.full As diet largely reflects foraging strategies of the big cats, spatiotemporal overlap between predator and prey may affect the composition of carnivore diet (Kronfeld-Schor and Dayan 2003, Weckel et al. 2006). Our research supports this assertion. We discovered that tigers are mainly nocturnal and crepuscular in our study area, which was similar to the activity reported for tigers in Nepal and India (Carter et al. 2012, Karanth et al. 2017) but contrasted with that of tigers in Malaysia (Rayan and Linkie 2015), where tigers showed a strong diurnal pattern. These differences were partially reflected in tiger–prey temporal interaction across the sites. Apparently, the activity of tigers maximizes their encounters with wild boar, the ungulate species that was most preferred, despite their relatively low abundance and obvious low spatial overlap with tigers. This result suggests that synchronized activity between tigers and wild boar likely facilitates a high level of tiger predation on this prey species which may represent an optimization of foraging time to maximize energetic gain. Contrary to our prediction, however, the activity of tigers was considerably different from that of the two deer species they selectively consumed (i.e. roe and sika deer). Tigers exhibited a similar space use pattern to that of sika deer. This indicates that Amur tigers use habitat where sika deer are densely populated, as also shown by Wang et al. (2016, 2017) in our study area. Conversely, the spatiotemporal partitioning reduced the possibility for chance encounters between tigers and the mostly diurnal roe deer, revealing that tigers may opportunistically prey on roe deer. In terms of energy rewards, roe deer are poor-quality prey for tigers because of the high energetic costs involved in capturing this small, wary and active species (Miller et al. 2014). Overall, the temporal or spatial synchronization of two large ungulates (sika deer and wild boar) with tigers increased their encounter likelihood at each camera-trap station, resulting in tigers preferentially hunting them. Also, we would like to point out that camera placement decisions and biological interactions (e.g. landscape of fear and interaction between ungulates) may influence the spatial overlap between tiger and prey, which requires further study. It has been demonstrated that carnivore habitat use is focused on those areas where prey are more vulnerable and/or where prey are more abundant (Hopcraft et al. 2005, Balme et al. 2007, Petrunenko et al. 2016). In Sik-hote-Alin Biosphere Zapovednik of the Russian Far East, Petrunenko et al. (2016) discovered that tiger habitat use and home range establishment are affected by the abundance and vulnerability of red deer and wild boar in the landscape but are not significantly affected by those of sika deer or composite maps where all three prey species occur together. Our results might suggest that tigers use habitat within their home range where sika deer and wild boar are densely populated due to red deer's absence in our region.
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Tiger
Apr 5, 2022 10:00:20 GMT -5
Post by brobear on Apr 5, 2022 10:00:20 GMT -5
Limitations of the study and ways forward bioone.org/journals/wildlife-biology/volume-2019/issue-1/wlb.00508/Prey-selection-of-Amur-tigers-in-relation-to-the-spatiotemporal/10.2981/wlb.00508.full Like many other studies of the food habits of tigers based on scat analysis, our results have several limitations. In addition to the use of a small number of scat samples, this study did not consider selectivity in terms of the age and sex of prey. By examining kill sites, Miller et al. (2013) reported that Amur tigers present selectivity based on the sex and age of ungulates. For example, more than 67% of wild boar killed by tigers are subadults and piglets. Hence, the relative contribution of wild boars to the diet of tigers will decline when the body size of kills is taken into account. Given that the N-mixture models estimated the relative abundance of prey species (Barker et al. 2017), the lack of an independent assessment of animal densities in the environment was another substantial limitation in this study. The combination of multiple field methods, including camera trapping, faecal counts and transect line surveys, to enhance abundance estimates should be pursued.
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Tiger
Apr 5, 2022 10:02:29 GMT -5
Post by brobear on Apr 5, 2022 10:02:29 GMT -5
Reply #46 - Quote; By examining kill sites, Miller et al. (2013) reported that Amur tigers present selectivity based on the sex and age of ungulates. For example, more than 67% of wild boar killed by tigers are subadults and piglets. Hence, the relative contribution of wild boars to the diet of tigers will decline when the body size of kills is taken into account.
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Tiger
Apr 5, 2022 10:04:00 GMT -5
Post by brobear on Apr 5, 2022 10:04:00 GMT -5
It is worth noting that the primary prey also exhibited relatively low spatial overlap with tigers in winter (O = 0.16–0.35, Table 3) compared to the summer season (Dou et al. unpubl.). We speculated that snow is the main reason for this low spatial overlap because ungulates concentrated in valleys and their activity levels were reduced in the snowy winters (Miquelle et al. 1996). The activity ranges of large predators, such as Amur tigers, are consistent both seasonally and over multiple years (Hojnowski et al. 2012). A further study examining the diet and spatial and temporal habitat use in seasons other than winter will help us better understand resource use by tigers. Finally, competition with sympatric leopards and anthropogenic disturbances (human presence, cattle grazing, poaching, etc.) are also considered to be factors affecting prey abundance and the spatial use of tigers, and the mechanisms remain unclear. Therefore, future studies should seek to understand the impact of people and leopards on the food habits of tigers.
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Tiger
Apr 5, 2022 10:04:58 GMT -5
Post by brobear on Apr 5, 2022 10:04:58 GMT -5
Conservation implications bioone.org/journals/wildlife-biology/volume-2019/issue-1/wlb.00508/Prey-selection-of-Amur-tigers-in-relation-to-the-spatiotemporal/10.2981/wlb.00508.full Overall, prey selection by tigers is not just dependent on the body size of ungulates but apparently also on their behav-ioural flexibility in exploiting prey. The use of camera traps has greatly increased our ability to examine tiger–prey temporal and spatial relationships. The approach we applied can be used as a framework to simultaneously integrate food habit analysis with the distribution of predators and prey through time and space to enhance the comprehensive understanding of tiger foraging strategies. HNR supports a very low population of tigers (0.33–0.40 100km–2) (Xiao et al. 2016) presumably because of low prey densities resulting from habitat degradation. However, increased cattle grazing now has decreased the abundance of ungulate species and have become a major hurdle to the recovery of Amur tigers in China (Wang et al. 2016, 2017). We suggest that conservation concerns should be focused on implementing practices to gradually reduce cattle grazing levels and extent and increase the size of sika deer and wild boar populations in the park.
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Tiger
Apr 5, 2022 10:08:42 GMT -5
Post by brobear on Apr 5, 2022 10:08:42 GMT -5
*Note: Brown bears kill more adult male wild boars than do tigers, even though the tiger is a full-time hunter while the brown bear hunts far less often.
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Post by brobear on Apr 5, 2022 10:10:41 GMT -5
Only the brown bear is willing to go face-to-face against this beast.
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Tiger
Apr 5, 2022 11:07:20 GMT -5
Post by brobear on Apr 5, 2022 11:07:20 GMT -5
Reply #40 - Quote: Small prey species (e.g. badgers) were occasionally preyed upon, reflecting the avoidance of smaller prey by tigers (Karanth and Sunquist 1995, Sugimoto et al. 2016). Reply #43 - Quote: The body size, availability and vulnerability of prey are the primary factors determining prey selection. A recent meta-analysis (Hayward et al. 2012) suggests that species weighing between 60 and 250 kg are preferred by tigers, and in our study the two large prey, wild boar (103 kg) and sika deer (95 kg) were the preferred prey. The wild boar is the largest ungulate preferred by Amur tigers (Fig. 3), supporting the findings of Hayward et al. (2012); they report that the wild boar is one of the species most preferred by tigers based on selectivity index scores from 3187 kills or scats from 32 prey species. *Tigers prefer large prey animals to smaller prey animals, which can provide more meat. Exceptions to this rule is smaller wild boar as a large boar would give more fight. A tiger will stalk and ambush a wild boar weighing up to 103 kg ( 227 pounds ). Also, although tigers hunting bears is so seldom that bears are not even mentioned as prey in this study, a tiger will always chose a smaller bear.
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Tiger
Apr 7, 2022 1:44:09 GMT -5
via mobile
brobear likes this
Post by OldGreenGrolar on Apr 7, 2022 1:44:09 GMT -5
Only the brown bear is willing to go face-to-face against this beast. This beast can weigh up to 800 pounds. It is pretty dangerous. This means that a huge male wild boar can outweigh an average male Ussuri brown bear.
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Tiger
Apr 7, 2022 2:09:49 GMT -5
Post by brobear on Apr 7, 2022 2:09:49 GMT -5
Wild Boar Hunting in Russia www.russianhunting.com/de/wild-boar-hunting-russia/ There is no better place to hunt for a wild boar trophy than Russia. The Russian wild boar is essentially the same animal that populates all of Europe, Northern Africa and part of Asia. What makes the Russian wild boar uniquely different is the size of the trophies. Harsh winters with deep snow cover allow only the biggest boars to survive. In addition, predation by wolves, lynx and Siberian tiger in the Far East breads especially mean and strong animals. Many mature males will reach 200-300 kg. (440-660 lbs.), occasionally topping scales at over 350 kg. (770 lbs.). The density of the wild boar population in most of Russia is not as high as in Europe, or in the Muslim countries of Asia, but it is well compensated by the quality of the trophies, which will frequently have tusks of over 24 cm. (10 in.) with record trophies reaching 30 cm. (12 in.). When confronted, this animal can be extremely dangerous, and big hogs may not hesitate to attack a brown bear when defending themselves. Hunts, especially early in the season are usually conducted from the stands positioned close to boar’s favorite feeding grounds: different crop fields. With snow on the ground driven hunts are the most successful. In some parts of the country stalking, or using dogs is the method of preference.
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Tiger
Apr 7, 2022 2:18:19 GMT -5
Post by brobear on Apr 7, 2022 2:18:19 GMT -5
shaggygod.proboards.com/thread/709/wild-boar Rakov, N.V. (1970) Causes of mortality of the wild boar and its interrelation with predators in the Amur territory. Zoologicheskii Zhurnal "In years of crop failure, brown bears are well adapted to the hunt wild boars.Bears do kill boar of all ages and classes.(Including adult and prime male wild boar)" When the Ussuri brown bear goes hunting, wild boar and red deer are his top two prey choices.
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Tiger
Apr 9, 2022 2:19:57 GMT -5
Post by brobear on Apr 9, 2022 2:19:57 GMT -5
From my book, 'Land of the Bear' by Denny Geurink ( 2014 ). Russia is called Land of the Bear for a reason. Out of the 200,000 brown bears roaming the northern hemisphere in a dozen or more countries, approximately two-thirds of them, or 120,000 bears, reside in Russia. Compare that to the 32,000 found in the United States - of which 95 percent live in Alaska - and the 21,000 found in Canada, and you get a pretty good picture of why the brown bear is so closely identified with Russian culture. The brown bear is one of the most widespread and popular animals in Russia, where it has been long considered to be the country's national symbol. It appears on coins, flags, street signs, maps, billboards, and even beer bottles. In 1980 the brown bear was chosen as the official mascot of the Moscow Olympics. From my book, ‘Land of the Bear’ by Denny Geurink: There are several reasons why there are so many brown bears in Russia. First, the habitat is perfect for them. The country is covered with dense forests and wilderness areas flush with the perfect bear foods, from the salmon-rich Kamchatka Peninsula to the pine nut rich forests of Siberia. Secondly, the human population in Russia is very widespread. Once you get outside the major cities, the population is very rural. Thirdly, after the Bolshevik Revolution in 1912, guns and hunting disappeared from Russia. This allowed bear populations to explode. While this is good for the bear, it wasn’t always so good for the rural Russian population.
With so many bears in Russia, and so many remote villages located in bear habitat, its no wonder that there are five times as many people killed by bears in Russia as there are in the United States. Studies show that, on average, there are two recorded fatal bear attacks a year in the United States; there are at least 10 fatal attacks a year in Russia. A lot more people are attacked and not killed. In years there is a poor salmon run or pine nut crop, these numbers can double.
There are documented cases in Eastern Siberia where some bears have become man-eaters during times when natural foods are scarce. At least two bears in this region have been identified as killing and eating 12 people each.
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Tiger
Apr 9, 2022 5:31:20 GMT -5
Post by brobear on Apr 9, 2022 5:31:20 GMT -5
Sus scrofa - wild boar Wild boars (Sus scrofa) are a cosmopolitan species. They originated in Europe and Asia, but were widely introduced to North America and are considered an invasive species in the southeastern United States and California. They are common throughout Eurasia, and inhabit every continent except Antarctica. (Chapman and Trani, 2007; Oliver and Leus, 2008; Wood and Barrett, 1979) Habitat Given their wide distribution, wild boars can be found in a variety of habitats. They may inhabit grassy savanna areas, wooded forests, agricultural areas, shrublands and marshy swamplands. They require a nearby water source and shelter (dense vegetation) to protect and conceal them from predation. They thrive in an assortment of climates, but generally avoid extreme heat or cold. In places that may experience harsh winter temperatures and increased snowfall, the population density may be limited by food sources. Deeper snows and frozen ground inhibit their ability to forage for roots and foliage. (Chapman and Trani, 2007; Melis, et al., 2006; Oliver and Leus, 2008) Physical Description Wild boars range from 153 to 240 cm in total length and weigh 66 to 272 kg as adults. Females tend to be smaller than males of the same age, with the size difference becoming more apparent as the animals age. Adult wild boars have a thick, coarse coat of hair covering their bodies. Their coat ranges in color from black to brownish-red to white. Depending on their geographic location, they can have a speckled or solid pelage color. They may also have longer bristly hairs that grow down the middle of their backs. At birth, young boars generally have yellowish-brown stripes running down their backs that disappear into an even coloration within about 4 months. Wild boars can stand as tall as 0.9 m at their bulky shoulders, tapering off towards their hind quarters. Their tails measure 21 to 38 cm, and their ears are 24 to 26 cm long. Their upper canine teeth typically measure 5 to 10 cm and are generally larger than their lower canines. Their upper canines are usually visible even when their mouth is closed. Their dental formula is I 3/3, C 1/1, P 4/4, M 3/3 = 44. (Chapman and Trani, 2007; De Magalhães and Costa, 2009; Ickes, 2001; Webster, et al., 1985) Reproduction Wild boars tend to live in large groups called sounders that are made up of 6 to 20 closely-related females, but may contain over 100 individuals. As the sows prepare to give birth, they temporarily leave the sounder and return with their young upon farrowing (giving birth to their litter). Even after reaching maturity, female piglets tend to stay in the same groups in which their mothers reside. These herds tend to have some overlap, and it is not uncommon for herds to split into subpopulations. Males stay with their mothers until they are 1 to 2 years old and then leave the herd. After departing, they generally only join a sounder during mating season. Polygynous males are attracted to groups of females that are in estrous. They become very aggressive and compete for the opportunity to breed with a sounder. Successful males chase females in estrous, nudging them to show their interest. If the female is also interested, she may respond by urinating. If the female does not urinate, the male may give up after several minutes. (Graves, 1984; Iacolina, et al., 2009; Oliver and Leus, 2008) Wild boars are capable of reproducing at any time during the year. Mating is usually dependent on the climate, which can directly affect food availability. If the nutritional needs of the females are not being met, breeding can be suppressed. Females become capable of reproducing around the age of 10 months, and males are sexually mature at approximately 5 to 7 months. Sows are polyestrous, and can produce up to two litters per year. Estrous cycles generally last 21 to 23 days. A sow's gestation period lasts 108 to 120 days. Each litter consists of 5 to 6 piglets on average. Newborn piglets weigh 0.4 to 0.8 kg and are weaned at 8 to 12 weeks. They continue to grow until age 5 to 6. Interestingly, males have more testosterone in their bloodstream during the winter months and shorter days equate to higher concentrations of sex hormones in the boar's semen plasma. (Chapman and Trani, 2007; Goulding, 2013; Henry, 1968; Kozdrowski and Dubiel, 2004; Webster, et al., 1985; Wood and Barrett, 1979) Males do not give any parental care as they are polygynous and usually travel alone. Female parental care is likely lower in this species than in sheep, cattle, and goats, which could be a trade-off for larger litter sizes. While these comparable species generally only have 1 or 2 young per litter, wild boar litters are 2 to 3 times this size. Not surprisingly, piglets have a high mortality rate. At birth, piglets have very little body fat and few energy stores. By producing more young, female boars increase the chances that some offspring will survive. Sows with large litters have been known to accidentally crush their progeny. However, research suggests that this may be purposeful, to increase the odds of survival for the rest of the litter. Reduced competition among siblings for feeding is a result of smaller litter sizes. Weaker piglets may try to feed several times, before being beaten out by their siblings, and simply dying from malnourishment. Females farrowing piglets close to the same time within a sounder may allow piglets from another litter to nurse. However, more often sows reject piglets that are not their own. Females work collectively to protect all offspring within their sounder. When traveling, mothers keep their young in the middle, with adults in the lead and rear. Young are often left with one female as protection, while the rest of the group forages for food. (Andersen, et al., 2011; Drake, et al., 2008; Graves, 1984) Lifespan/Longevity The maximum known lifespan of a wild boar in their natural habitat is 9 to 10 years. On average, they only live to be 1 to 2 years old. There are few reliable sources regarding their survival rates in the wild. One subspecies, Sus scrofa riukiuanus, reportedly lived 27 years in captivity. Mortality for both male and female boars in the wild is greatly affected by pressures due to hunting. When sport hunting, it is likely that older males will be harvested because they are considered trophy animals. This can skew longevity numbers towards lower lifespans for males, particularly older males. (Braga, et al., 2010; De Magalhães and Costa, 2009; Jezierski, 1977; Toïgo, et al., 2008) Behavior Female wild boars are social animals that tend to live in groups. These groups, called sounders, are generally made up of several females and their offspring. They move their home range as needed, according to resource availability and weather. Males tend to be more solitary after reaching maturity and join with groups during mating. Depending on their habitat, wild boars may be active both day and night. In seasonally warmer weather, they tend to stay fairly inactive during the day. They stay in the shade and wallow in water sources to keep cool. This protects them from insects and helps remove ectoparasites. If boars actively feed during the day, they tend to avoid open areas that would make them more vulnerable to predation. In cooler conditions, these boars may feed during the day, but foraging activities usually increase in the late evening. During the evening and night, wild boars emerge in open areas to search for food. (Boitani, et al., 1994; Graves, 1984; Webster, et al., 1985) Home Range Their home varies with several factors including the number of individuals in the group, food resource availability, geographic range, and predation threats. Females tend to occupy a smaller region and keep to covered areas within a home range to protect themselves and their young. Groups of females accept some overlap between their herd and others, but sounders remain distinct groups. Males are inclined to occupy a larger area. They tolerate overlap of ranges with other males, but during mating season, they become more territorial as they prepare to compete for breeding rights. On average, wild boars have territorial sizes of 1.1 to 3.9 square kilometers. (Boitani, et al., 1994; Graves, 1984)
Communication and Perception Wild boars communicate vocally, using growls to indicate aggressive behavior and squeals to show excitement and approachability. Their long, flattened snouts allow for a heightened sense of smell. As pigs forage for food, they tend to keep their snout near the ground. This can impede their ability to smell, making it harder to smell possible danger. They also use chemicals to interact with each other. By rubbing on the ground, they can leave chemical traces behind. Their eyes are located on the sides of their head, giving them good peripheral vision. They mostly rely on their well-developed sense of smell and hearing. There has been very little research on sow-piglet recognition, but in the domesticated subspecies, Sus scrofa domesticus, studies show that sows use their incredible sense of smell to distinguish their own piglets verses piglets from other litters just 24 hours post-partum. (Graves, 1984; Maletínská, et al., 2002; Morton, 1983) Food Habits Wild boars are omnivorous. They predominantly eat plant matter, particularly crops, fruits, nuts (mast), roots, and green plants. They have also been known to consume bird eggs, carrion, small rodents, insects, and worms. Wild boars have reportedly preyed on small calves, lambs, and other livestock when the opportunity presents itself. They adjust their diets based on what is available, which can vary with seasons, weather conditions, and locations. They tend to do most of their foraging in the late evening and into the night. (Chapman and Trani, 2007; Graves, 1984; Schley and Roper, 2003; Webster, et al., 1985) Predation Humans are the main predator of wild boars. Wild boars can be destructive to farmland and natural ecosystems causing humans to implement removal procedures. Young wild boars are targeted by predatory animals such as coyotes and bobcats, while juveniles and adults may fall prey to larger predators such as American black bears and cougars. Adults use their coloration to help them blend in with their surroundings. Piglets have stripes running the length of their back, enabling them to remain concealed within undergrowth and in their nest. By traveling in sounders, sows are able to collectively protect their young from predation while on the move. When traveling, sows lead and pull up the rear while the piglets are kept in the middle of the herd. (Chapman and Trani, 2007; Fang, et al., 2009; Graves, 1984; Webster, et al., 1985) Ecosystem Roles Wild boars often have a negative effect on the ecosystems, especially if they are an introduced species. They can be very destructive to the habitats of other animals in the area. When nesting in preparation to give birth, females use saplings and other woody plants that they either break off or uproot completely, impacting the ability of new trees to grow. When grubbing for food, they may displace soil and small undergrowth, encouraging erosion and soil deterioration. Studies have shown that seed survival and success, as well as species richness for many plants decreases in plots of land that wild boars can access. Wild boars host a variety of parasites including Trichinella species, Toxoplasma gondii, Gongylonema species, lungworms, kidney worms, stomach worms, ascarids, whipworms, American dog ticks, and hog lice. Many of these are transmissible to humans and other animals. While the parasites may directly lead to death, in most instances they cause the animal's health to deteriorate and they succumb to various environmental elements. Wild boars and their young provide a food source for various animals including bobcats, coyotes, and cougars, among others. (Chapman and Trani, 2007; Henry and Conley, 1970; Ickes, 2001; Ickes, et al., 2005; Meng, et al., 2009) Economic Importance for Humans: Positive An important economic pastime that has risen in popularity is recreational fee-hunting for various wild animals, including wild boars. It is very beneficial to both wildlife and landowners. There are monetary incentives for the proprietors, which allows them to take better care of their property. This in turn gives the various animals that may be kept there a good habitat. At the same time, this helps keep down the population of wildlife like wild boars who can be destructive when present in large numbers, and allows for some control on how many animals are being harvested. Hunting on wildlife reservations also increases the likelihood that safe hunting practices will be implemented. Wild boars are one of the most popular wild animals hunted for both sport and food. They are hard to get rid of once a population establishes itself, and so numbers may dwindle, but generally the herds bounce back. Domestic pigs are also desirable as a food source for humans, as well as a source of income for farmers. They become sexually mature at a young age and may reproduce up to twice a year, producing large amounts of offspring, quickly increasing populations for either hunting or harvesting for consumption. (Butler, et al., 2005; Graves, 1984; Oliver and Leus, 2008) Economic Importance for Humans: Negative Wild boars can be very problematic for farmers. Crops are often susceptible to damage where wild boars are prevalent. While foraging for food and seeking shelter, they often trample through farm fields. In addition, wild boars have the potential to harbor several diseases and parasites that may be transmissible to domestic livestock and humans. Livestock often contract diseases from being in close proximity with wild boars. Humans may come into contact with infection by either ingesting the meat of a domestic animal that came into contact with an infected wild boar, or eating the meat of a sick wild boar. The damage caused by wild boars can be very costly, especially to farmers. In addition to losing money on their damaged crops and either loosing or having to treat their infected livestock, they may have to build better barriers to keep the wild boars out. Damage caused by introduced wild boars can be so detrimental to some environments that it may lead to endangerment and extinction of native flora and fauna. In particular, the Galapagos Archipelago has had major repercussions since their introduction shortly after Darwin's visit to the islands. Because of their omnivorous foraging tendencies, these pigs have wreaked havoc on many of the islands indigenous plants and animals alike. Eradication measures have been implemented since the late-1960s and have proved successful in purging the foreign species from Santiago Island in particular, the largest introduced pig removal. Close to 19,000 wild pigs were eliminated from the island. (Cruz, et al., 2005; Geisser and Reyer, 2004) Conservation Status Most wild boar populations are in no danger of becoming endangered or extinct. In fact, there are many programs in place to help control and reduce their populations around the world. They have become a nuisance in places where they were introduced and prove to be difficult to regulate once they are established. Studies have shown that hunting is the most effective way to stabilize their numbers. Other options include installation of fencing, trapping, and strategically placed feeders to lure the boars away from inhabiting undesired areas. There are limits in place for hunting such as seasons and bag limits to ensure they are not over-harvested. There are also specific hunting methods that may be implicated depending on what end result is desirable. "Espera" hunting is done at night using bait to lure wild boars. This allows for a more precise harvest because it gives the hunter more time. If the purpose of hunting is to rid or thin out populations, this helps hunter determine the gender and age of the boar. Due to religious restrictions on the consumption of pork, some countries observe an increase in their local wild boar populations. One subspecies, Sus scrofa riukiuanus, was placed under the 'vulnerable' status in 1982. Widespread development of the Ryukyu Islands has threatened many endemic species, including this subspecies. They are thought to be endangered on several of the islands, although they have not been officially listed. A national park has been established, but increasing expansions looming on the horizon plan to use some of the land for roadways that will limit their habitat and give easier access to poachers who have already wiped out over half of the preserved wild boar population. (Braga, et al., 2010; Chapman and Trani, 2007; Geisser and Reyer, 2004; Oliver and Leus, 2008; Webster, et al., 1985)
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Tiger
Apr 9, 2022 5:34:11 GMT -5
Post by brobear on Apr 9, 2022 5:34:11 GMT -5
*Normal max for male Russian wild boar, 272 kg or 600 pounds, although larger specimens have been weighed. This can place the wild boar at weight-parity with a full-grown male Ussuri brown bear.
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Tiger
Apr 9, 2022 6:40:45 GMT -5
Post by brobear on Apr 9, 2022 6:40:45 GMT -5
a-z-animals.com/blog/discover-the-largest-wild-boar-ever/ There are 16 recognized subspecies of wild boars. Let’s take a look at some of the largest wild boar subspecies. Largest Wild Boar Subspecies: Ussuri Boar The Ussuri Boar (S. s. ussuricus) is thought to be the largest of the wild boars. The Ussuri subspecies is found in Eastern China and parts of Russia, including the Ussuri Bay and Amur Bay. Adult males are often found above 500 pounds, with some individuals weighing even more. The weight of a Ussuri Boar (or any wild boar for that matter) will vary wildly depending on environmental factors like food and water availability. Carpathian Boar The Carpathian Boar (S. s. attila) is a large boar subspecies found in Ukraine, Romania, Hungary, and nearby areas. The average Carpathian boar weighs over 300 pounds, with some individuals reaching massive sizes of over 800 pounds when food is abundant. This subspecies will generally have dark hair and longer lacrimal bones (eye sockets). Middle Asian Boar The Middle Asian Boar (S. s. nigripes) is another large subspecies that can be found around Kazakhstan, Mongolia, Afghanistan, and nearby countries. Just like with other species, the maximum weight of a Middle Asian Boar fluctuates wildly depending on habitat and resource availability. Many individuals have been found to weigh over 500 pounds. The Middle Asian Boar features a lighter coat than many other related subspecies—much closer to a light gray than the usual dark brown or black.
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