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Studies on the relationship between habitat heterogeneity and animal abundance are essential for understanding what determines biodiversity. Transect-based direct observations of eight principal prey species of tiger in the Chitwan National Park (CNP) were used to determine their abundances and habitat preferences. Chital was the most abundant prey species of tiger (Panthera tigris). Each of the prey species had significantly different habitat preferences except sambar deer and chital. Habitat preference was measured using Manly’s preference index, which revealed that short grassland, mixed forest, and riverine forest were the most preferred habitats of the prey species. The results indicate that large species of deer tend to be found in more diverse habitats than small species, except muntjac. The abundance of the principal prey species of tiger was positively correlated with habitat heterogeneity. The habitat, which contributes significantly to the heterogeneity of the landscape, is grassland in large patches of forest. The ongoing increase of forest cover in the CNP has led to a reduction in the area of grassland, which may negatively affect the abundance of the prey species of tiger. Hence, it is suggested that the restoration of landscape heterogeneity is the best way to manage the habitats in the CNP.
Density of tiger Panthera tigris and leopard Panthera pardus was estimated using photographic capture–recapture sampling in a tropical deciduous forest of Mudumalai Tiger Reserve, southern India, from November 2008 to February 2009. A total of 2,000 camera trap nights for 100 days yielded 19 tigers and 29 leopards within an intensive sampling area of 107 km2. Population size of tiger from closed population estimator model Mb Zippin was 19 tigers (SE = ±0.9) and for leopards Mh Jackknife estimated 53 (SE = ±11) individuals. Spatially explicit maximum likelihood and Bayesian model estimates were 8.31 (SE = ±2.73) and 8.9 (SE = ±2.56) per 100 km2 for tigers and 13.17 (SE = ±3.15) and 13.01 (SE = ±2.31) per 100 km2 for leopards, respectively. Tiger density for MMDM models ranged from 6.07 (SE = ±1.74) to 9.72 (SE = ±2.94) per 100 km2 and leopard density ranged from 13.41 (SE = ±2.67) to 28.91 (SE = ±7.22) per 100 km2. Spatially explicit models were more appropriate as they handle information at capture locations in a more specific manner than some generalizations assumed in the classical approach. Results revealed high density of tiger and leopard in Mudumalai which is unusual for other high density tiger areas. The tiger population in Mudumalai is a part of the largest population at present in India and a source for the surrounding Reserved Forest.
Eight founders and thirty-one descendants were sampled as the Founder group and the Offspring group respectively from a captive population of Amur tigerPanthera tigris altaica Temminck, 1844 for population genetic analysis with RAPD and ISSR markers. Integrated with demographic data during the initial recovery stage, results showed: (1) increasing the population size (N) and the effective population size (N e) greatly retard lose of genetic variation induced mainly by genetic drift and selection; (2) recombination and admixture could cause the Offspring group (5.711%) and the Founder group (10.383%) to hold different linkage disequilibrium (LD); (3) further Ohta’s variance analysis indicated genetic drift (87.3%) and epistatic selection (12.7%) maintained LD in population, whereas GENEDROP analysis supported epistatic selection largely derived from artificial selection of managers; (4) both Tajima’s test and Fu’s test confirmed the statistic neutrality of genetic markers used, moreover the positive value of Tajima’sD (0.090) together with the result that π (25.286) was bigger than ϑ (24.898) revealed the Founder group was admixture population, while the negative Tajima’sD value (−0.053) together with the result that π (23.679) was less than ϑ (23.912) disclosed the Offspring group experienced selective sweep.
Environmental and social pressures can result in interspecies differences in marking behaviours. There is a strong relationship between marking behaviour and the environment. Therefore, closely related species that show behavioural differences in the wild may have different scent marking strategies. We conducted a comparative study of the urine-marking behaviours of tigers and lions in captivity (Madrid Zoo, open enclosures of 514 m² and 730 m² respectively, observations of 8 animals for each species). These two closely related species have different natural habitats. We observed interspecific differences in the rates, seasonal variations, and durations of the urine-marking acts. The marking rate was higher in tigers, which also showed seasonal variations not observed in lions. The duration of urine marking was lower in tigers than in lions. These differences seem to correspond to differences between tigers and lions in terms of their natural habitats (forest areas vs open areas), social organizations (solitary vs social), and reproductive biology patterns (seasonal polyoestrous vs annual polyoestrous).
Buxa Tiger Reserve (BTR) is located in Alipurduar Sub Division of West Bengal, India. It comprises of the entire forest area of the erstwhile Buxa Forest Division (Created in 1877 – 78) and some territory of the erstwhile neighboring Cooch Behar Forest Division. The Reserve lies between Latitudes 23o30′ N to 23o50′ N and Longitudes 89o25′ E to 89o55′ E. The total area of the reserve is 760.87 km2 of which 385.02 km2 has been constituted as the Buxa Sanctuary and National Park (Core zone of the BTR) and the balance 375.85 km2 areas is treated as a buffer zone. It has 37 forest villages and 4 fixed demand holdings, 46 revenue villages and 34 tea gardens in and around it. The survey work was done in May, 2015 by visiting a forest edge village, 28 Mile, in Buxa Tiger Reserve and the primary data were gathered through field survey and direct contact with common people and authorized centres of the region. Surveys on the demography, agriculture, livestock management, water management, education, culture, health, waste management, disaster management, transport, biodiversity, joint forest management activities, Non-timber forest product usage and human animal conflict were done in this area. In every phase of the survey work, photographic documentation was done. In spite of being positioned in a diverse and sensitive ecological zone, the village is not adequately managed. There is an urgent need for implementing sustainable management systems in the areas for the betterment of the socio-environmental structures. Some of the possible management strategies have been suggested for maintaining the social, environmental, economic and ecological balance of the region.
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