The Experts below are selected from a list of 111 Experts worldwide ranked by ideXlab platform
Weikang Yang - One of the best experts on this subject based on the ideXlab platform.
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different environmental requirements of female and male siberian ibex Capra Sibirica
2021Co-Authors: Lei Han, Zhi Wang, David Blank, Muyang Wang, Weikang YangAbstract:In sexually dimorphic species, males and females may select different habitat for greater fitness. However, the key factors that play a leading role between sexes in habitat selection are still poorly understood. In this paper, we investigated the possible causes of the differences in habitat preference between male and female Siberian ibex (Capra Sibirica) living in the Tianshan Mountains (China). Using the Maximum entropy model, we found that the ruggedness and elevation of the terrain were the most important factors affecting habitat selection in Siberian ibex. Females preferred the most rugged terrain to increase the security of their young and themselves, while males favored moderately rugged terrain to provide sufficient safety from predators, and availability of suitable forage simultaneously. Females used a wider variety of elevations to search for newly emerged vegetation for its higher nutritional value, while males preferred more elevated slopes to avoid the higher temperatures and greater presence of biting insects found at the lower elevations. In addition, females were associated more with rivers due to their higher water demands. The differences in habitat selection between Siberian ibex males and females depend on multiple considerations, but only a limited number of key factors determine their actual distribution.
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vigilance behaviour in siberian ibex Capra Sibirica effect of group size group type sex and age
2020Co-Authors: Lei Han, David Blank, Muyang Wang, Weikang YangAbstract:Gregarious prey species modify their behaviours in response to predation risk in two ways: by increasing vigilance level or enlarging herd size. However, individuals of various sex and age have different responses to the same danger, and even the same individuals react differently depending on their status during biological events or within group types. But how these factors influence the interactions between vigilance level and group size is still poorly understood. Therefore, we studied this phenomenon by observing and analyzing the behaviours of the Siberian ibex (Capra Sibirica) in the Eastern Tian-Shan Mountains (China). We found that similar to many other gregarious ungulates, Siberian ibex demonstrated a decrease in vigilance level with an increase in group size, since staying in larger groups increased the probability of predator detection and reduced the possibility of being captured. In general, males were more vigilant than females during the rut due to the sharp increase in their social alertness to achieve greater success in reproduction. In contrast, females were more vigilant than males out of rutting time, particularly significantly following parturition, since mothers spent a lot of their energy in maternal care, which coupled with having small and unexperienced newborns, made them more vulnerable to predation than other conspecifics. Siberian ibex had the same vigilance level in summer and winter, because of seasonally opposite trade-offs between feeding duration and vigilance level based on seasonal changes in food availability. Individuals in mixed-sex and female groups were more often targeted by predators, prompting individuals from these groups to be more vigilant than in male groups. The vigilance level in males decreased with age likely because of their increased body size and enhanced vigilance experience, which reduced their risk of predation. Our study confirmed that the Siberian ibex' vigilance level inversely correlated with group size, but other various factors, such as forage biomass/quality, sex, biological cycle, group types and age, had significant impacts on their interrelationship.
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grouping patterns and social organization in siberian ibex Capra Sibirica feeding strategy matters
2019Co-Authors: Lei Han, David Blank, Muyang Wang, Weikang Yang, Antonio Alves Da Silva, Joana AlvesAbstract:A study on group size and composition in Siberian ibex (Capra Sibirica) was conducted in the Eastern Tien-Shan Mountains. We found that small groups (1-5 individuals) were most common for this species. Generally, mixed-sex groups were larger than male and female groups. Since males have more ability for fiber digestion, because of their larger body size than females, they are less selective in food quality. Due to this, males gathered into larger single-sex groups in August-September, when forage was at its maximal biomass, and into smaller groups when the amount of food was limited (winter-early-spring). During birthing period, pregnant females typically separated from groups to give birth, returning to the female groups in May-June, when high-quality food was at its maximal availability, making female groups largest in this period. Similar to other sexually dimorphic species, Siberian ibex females and males stayed together in mixed-sex groups during rutting season, demonstrating sexual segregation outside of the rutting season, particularly during summer. Nevertheless, there are still a significant number of males and females that stay in mixed-sex groups throughout the year. In conclusion, the grouping pattern and social organization of Siberian ibex were closely correlated to the availability and quality of their food supply and yearly breeding cycle. Accordingly, Siberian ibexes changed their feeding strategy: being mixed feeders they behaved similar to concentrate selectors when food was scant and preferred small sized groups; while they enlarged their group sizes during seasons when the enriching of forage conditions allowed them to do that. However, group enlarging happened in different months depending on group typology (i.e. mixed-sex, male or female groups) depending on the feeding strategy of their individuals.
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winter daytime activity budgets of asiatic ibex Capra Sibirica in tomur national nature reserve of xinjiang china
2012Co-Authors: Weikang YangAbstract:Asiatic Ibex, Capra Sibirica, is distributed only in the mountains of central Asia, and is a threatened species in China. Although the ecology of the C. ibex and C. walliae (C. Nubiana waliae) have been well studied in Europe and Africa, little information is available on the species of Asiatic ibex in Asia. Since knowledge of the time activity budget can provide useful information for ibex conservation and management, we studied the daytime activity budgets of the Asiatic ibex in Tomur National Nature Reserve (TNNR) of Xinjiang, China. The results showed that both female and male ibex spent most of their time feeding: females spent significantly more time feeding than males (Kruskal-Wallis tests, χ 2 =4.935, d.f.=1, P=0.026), while males spent significantly more time standing than females (Kruskal-Wallis tests, χ 2 =7.676, d.f.=1, P=0.006). In addition, the Asiatic ibex showed two distinct activity peaks during the day when they were most activity: early morning from 7:00 to 8:30 and around sunset from 15:30 to 19:30.
Yash Vee Hatnaga - One of the best experts on this subject based on the ideXlab platform.
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conflicts between traditional pastoralism and conservation of himalayan ibex Capra Sibirica in the trans himalayan mountains
2004Co-Authors: Sumanta Agchi, Charudu Mishra, Yash Vee HatnagaAbstract:There is recent evidence to suggest that domestic livestock deplete the density and diversity of wild herbivores in the cold deserts of the Trans-Himalaya by imposing resource limitations. To ascertain the degree and nature of threats faced by Himalayan ibex (Capra Sibirica) from seven livestock species, we studied their resource use patterns over space, habitat and food dimensions in the pastures of Pin Valley National Park in the Spiti region of the Indian Himalaya. Species diet profiles were obtained by direct observations. We assessed the similarity in habitat use and diets of ibex and livestock using Non-Metric Multidimensional Scaling. We estimated the influence of the spatial distribution of livestock on habitat and diet choice of ibex by examining their co-occurrence patterns in cells overlaid on the pastures. The observed co-occurrence of ibex and livestock in cells was compared with null-models generated through Monte Carlo simulations. The results suggest that goats and sheep impose resource limitations on ibex and exclude them from certain pastures. In the remaining suitable habitat, ibex share forage with horses. Ibex remained relatively unaffected by other livestock such as yaks, donkeys and cattle. However, most livestock removed large amounts of forage from the pastures (nearly 250 kg of dry matter/day by certain species), thereby reducing forage availability for ibex. Pertinent conservation issues are discussed in the light of multiple-use of parks and current socio-economic transitions in the region, which call for integrating social and ecological feedback into management planning.
Klaus Hacklander - One of the best experts on this subject based on the ideXlab platform.
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responses of snow leopards wolves and wild ungulates to livestock grazing in the zorkul strictly protected area tajikistan
2018Co-Authors: Khalil Karimov, Shannon Kachel, Klaus HacklanderAbstract:Long recognized as a threat to wildlife, livestock grazing in protected areas has the potential to undermine conservation goals, via competition, habitat degradation, human-carnivore conflict and disruption of predator-prey relationships. In the Strictly Protected Area Zorkul in Tajikistan (Zorkul Reserve), grazing is commonplace despite official prohibition, with potentially detrimental effects on local fauna, in particular, snow leopard Panthera uncia, wolf Canis lupus, brown bear Ursus arctos, argali sheep Ovis ammon, Asiatic ibex Capra Sibirica, and long-tailed marmot Marmota caudata. To understand the impacts of grazing and associated human pastoralism on the large mammal community in Zorkul Reserve we used data from camera traps to build models of ungulate and carnivore site use intensity, and we investigated carnivore summer diets using microscopic scat analysis. While sample sizes limited our inference for several species, we found that site use of the most common ungulate, argali, decreased with proximity to herder’s camps, indicating possible displacement into sub-optimal habitats. However, no such pattern was present in carnivore site use. For wolf and snow leopard, the most frequently encountered prey items were argali and marmot, while bear depended almost exclusively on marmot. While current pastoralist practices in the reserve may not be incompatible with wildlife presence, our findings suggest that pastoralism may negatively impact ungulates by displacing them from otherwise suitable habitats, with unknown fitness consequences for ungulates or the predators that depend upon them. Managing Zorkul Reserve and other actively grazed protected areas to meet potentially competing demands of local pastoralist communities and conservation will require careful consideration of such interactions to minimize the risk of cascading negative impacts on wildlife.
Shannon Kachel - One of the best experts on this subject based on the ideXlab platform.
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responses of snow leopards wolves and wild ungulates to livestock grazing in the zorkul strictly protected area tajikistan
2018Co-Authors: Khalil Karimov, Shannon Kachel, Klaus HacklanderAbstract:Long recognized as a threat to wildlife, livestock grazing in protected areas has the potential to undermine conservation goals, via competition, habitat degradation, human-carnivore conflict and disruption of predator-prey relationships. In the Strictly Protected Area Zorkul in Tajikistan (Zorkul Reserve), grazing is commonplace despite official prohibition, with potentially detrimental effects on local fauna, in particular, snow leopard Panthera uncia, wolf Canis lupus, brown bear Ursus arctos, argali sheep Ovis ammon, Asiatic ibex Capra Sibirica, and long-tailed marmot Marmota caudata. To understand the impacts of grazing and associated human pastoralism on the large mammal community in Zorkul Reserve we used data from camera traps to build models of ungulate and carnivore site use intensity, and we investigated carnivore summer diets using microscopic scat analysis. While sample sizes limited our inference for several species, we found that site use of the most common ungulate, argali, decreased with proximity to herder’s camps, indicating possible displacement into sub-optimal habitats. However, no such pattern was present in carnivore site use. For wolf and snow leopard, the most frequently encountered prey items were argali and marmot, while bear depended almost exclusively on marmot. While current pastoralist practices in the reserve may not be incompatible with wildlife presence, our findings suggest that pastoralism may negatively impact ungulates by displacing them from otherwise suitable habitats, with unknown fitness consequences for ungulates or the predators that depend upon them. Managing Zorkul Reserve and other actively grazed protected areas to meet potentially competing demands of local pastoralist communities and conservation will require careful consideration of such interactions to minimize the risk of cascading negative impacts on wildlife.
Richard P. Reading - One of the best experts on this subject based on the ideXlab platform.
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siberian ibex Capra Sibirica neonatal kid survival and morphometric measurements in ikh nart nature reserve mongolia
2017Co-Authors: Baatargal Otgonbayar, Sukhiin Amgalanbaatar, Suuri Buyandelger, Richard P. ReadingAbstract:Understanding the factors infl uencing survival of ungulate neonates facilitates successful management programs, particularly as they relate to population dynamics and adaptive species management. However, kid survival of near threatened Siberian ibex (Capra Sibirica) remains poorly understood. During 2005-2013, we captured and collared 21 ibex kids in Ikh Nart Nature Reserve in southeastern Mongolia, to monitor their survival and cause-specifi c mortality. We found no diff erences in morphometric measurements between male and female kids, except body mass being males weighing more than females. A total of 11 mortalities were documented and predations by red foxes (n=5, Vulpes vulpes) and grey wolf (n=1, Canis lupus) was the leading cause of the mortalities. Known fate models indicate the monthly survival of kids best explained by body mass and fi rst month of life (April-May + weight). Monthly survival estimates ranged from 0.077 (95% CI = 0.60-0.88) in April-May to 0.97 (95% CI = 0.90-0.99) in June-March, with an annual survival rate of 0.45 (95% CI = 0.24-0.68). We found little support for the hypotheses that body mass or birth date infl uenced survival; however, our small sample size limited the power of the analyses. Overall, our results indicated that predation and other factors led to high kid mortality during the period shortly after birth.
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Creating a model of habitat suitability using vegetation and ruggedness for Ovis ammon and Capra Sibirica (Artiodactyla: Bovidae) in Mongolia
2017Co-Authors: Nanette Bragin, Ganchimeg Wingard, Sukhiin Amgalanbaatar, Richard P. ReadingAbstract:Abstract Spatially-explicit wildlife habitat models, such as a Habitat Suitability Index Model (HSIM), are increasingly used to understand optimal environmental conditions needed for a species survival and viability. HSIM compares different environmental variables, including vegetation, slope, and aspect to determine optimal habitat for a species. HSIM can compare a species’ use of resources with availability and determine risks for a species viability. Furthermore, decision makers can use HSIM to make decisions regarding resources needed for species of concern and development of protected areas. We used a geographic information system to create a HSIM for Argali sheep ( Ovis ammon ) and Siberian ibex ( Capra siberica ), species of conservation concern in Mongolia. We used vegetation and ruggedness layers and compared argali and ibex use with habitat availability. Argali and ibex presence correlated with three habitat classes: dense rock, low-density shrub, and short grass/forb. We found no significance in correlation for ruggedness.
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siberian ibex Capra Sibirica home ranges in ikh nart nature reserve mongolia preliminary findings
2007Co-Authors: Richard P. Reading, Sukhiin Amgalanbaatar, David Kenny, Anthony J Denicola, Enkhtsetseg TuguldurAbstract:Siberian ibex ( Capra Sibirica ) remain poorly understood, as little is known about their ecology. We began studying ibex in Ikh Nart Nature Reserve, Dornogobi Aimag, Mongolia to better understand the species’ ecological needs and threats. In this paper we report on home range and core range sizes. We captured 27 ibex and fit them with radio telemetry collars using drive nets for adults and juveniles ( n = 22) and hand captures for neonatal kids ( n = 5). We collected 1,029 locations from September 2003 to February 2007. Throughout the study, 9 ibex with 40+ fixes used mean, annual home range sizes of 3,115.5 ± 504.2 ha using the Minimum Convex Polygon method. Home ranges calculated using the fixed kernel method were smaller: 475.9 ± 14.7 ha for 50% kernel and 1,808.0 ± 88.1 ha for 95% kernel. Ibex from different demographic groups (males vs. females and juveniles vs. adults) used remarkably similar home and core ranges; we found no significant differences among any demographic groups. Although not quantified, ibex mostly restricted their activities to areas with steep cliffs and rocky outcrops and home ranges overlapped extensively.
