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Nayak A.K.,Similipal Tiger Reserve | Yadav S.P.,National Tiger Conservation Authority | Behera S.,Similipal Tiger Reserve
Cutis | Year: 2014

Prey densities were estimated in Similipal Tiger Reserve, Odisha, India from January 2012 to October 2012 by applying line transect distance methods. Season wise available prey density data was collected. The pre-monsoon and Post-monsoon seasons prey data was analyzed separately. In total, seven prey items were found on the transect lines from various parts of the reserve core and buffer area in an area of 2530.41 km2. The common langur (Semnopithecus entellus) and rhesus macaque (Macaque mulata) population densities in the study area were the highest, followed by chital (Axis axis), wild pig (Sus scrofa), sambar (Rusa unicolor), barking deer (Muntiacus muntjac) and mouse deer (Tragulus kanchil). Common langur population was highest 10.2±2 SE/km2in pre-monsoon and 16±2.7 SE/km2in post-monsoon whereas mouse deer population was found to be low 0.6±0.2 SE/km2in pre-monsoon. Our preliminary results may indicate that in Similipal the density of the overall ungulates and each species seems to be fewer compared with other landscapes. Continuous prey population monitoring is going on in Similipal Tiger Reserve which may indicates the rising of prey populations in reserve subsequently. However, only one year data is presented here to know the preliminary prey status of this tiger reserve. Further analysis is under consideration in due course of prey population study. Therefore, the proper management plan is required for better conservation of the prey and their predator in Similipal Tiger Reserve. Source

Majumder A.,Wildlife Institute of India | Basu S.,Wildlife Institute of India | Sankar K.,Wildlife Institute of India | Qureshi Q.,Wildlife Institute of India | And 3 more authors.
Wildlife Biology in Practice | Year: 2012

Home ranges of three radio-collared Bengal tigers [one adult female (AF), one adult male (AM) and one sub-adult male (SAM)] were studied between March 2008 and December 2011 in Pench Tiger Reserve (PTR), Madhya Pradesh. Using 100% Minimum Convex Polygon (MCP), the estimated home ranges of AF (n= 750 locations), AM (n= 136 locations) and SAM (n= 739 locations) were 43 km2, 55.1 km2 and 52.2 km2 respectively. Using 95% Fixed Kernel (FK), the corresponding figures were 32.1 km2, 64.1 km2 and 19.1 km2. The core area of individual activity for each tiger, as determined by 65% FK, was 10.3 km2 for AF, 20.3 km2 for AM and 6.6 km2 for SAM. The estimated overlap area between AM and AF using 95% FK was 19.2 km2 (65%), whereas it was 15.4 km2 (48%) between AF and SAM. The AF recruited three, four and five cubs in her 1st (May 2008 and all died during post natal stage), 2nd (October 2008) and 3rd litter (October 2010) respectively. Minimum 44% of the original natal area was used by AF at the time of raising her 2nd litter and 46% in her 3rd litter. Though there was a gradual extension of the annual home range, as observed during the first two years (2008-2010), but the core activity area remained considerably the same for AF over the study period. The study revealed that a minimum of 25 to 30 km2 undisturbed area was required for a breeding female in PTR where both the wild prey density (348.2/km2) and biomass (12384.7 kg/ km2) were found to be high with adequate ground cover for the successful raising of cubs up to the dispersal stage. Pench and its surrounding forested habitat need to be protected for the breeding and dispersing tiger population. © 2012 A. Majumder, S. Basu, K. Sankar, Q. Qureshi, Y.V. Jhala, P. Nigam, R. Gopal. Source

Yumnam B.,Wildlife Institute of India | Jhala Y.V.,Wildlife Institute of India | Qureshi Q.,Wildlife Institute of India | Maldonado J.E.,Smithsonian Conservation Biology Institute | And 5 more authors.
PLoS ONE | Year: 2014

Even with global support for tiger (Panthera tigris) conservation their survival is threatened by poaching, habitat loss and isolation. Currently about 3,000 wild tigers persist in small fragmented populations within seven percent of their historic range. Identifying and securing habitat linkages that connect source populations for maintaining landscape-level gene flow is an important long-term conservation strategy for endangered carnivores. However, habitat corridors that link regional tiger populations are often lost to development projects due to lack of objective evidence on their importance. Here, we use individual based genetic analysis in combination with landscape permeability models to identify and prioritize movement corridors across seven tiger populations within the Central Indian Landscape. By using a panel of 11 microsatellites we identified 169 individual tigers from 587 scat and 17 tissue samples. We detected four genetic clusters within Central India with limited gene flow among three of them. Bayesian and likelihood analyses identified 17 tigers as having recent immigrant ancestry. Spatially explicit tiger occupancy obtained from extensive landscape-scale surveys across 76,913 km2 of forest habitat was found to be only 21,290 km2. After accounting for detection bias, the covariates that best explained tiger occupancy were large, remote, dense forest patches; large ungulate abundance, and low human footprint. We used tiger occupancy probability to parameterize habitat permeability for modeling habitat linkages using least-cost and circuit theory pathway analyses. Pairwise genetic differences (FST) between populations were better explained by modeled linkage costs (r.0.5, p,0.05) compared to Euclidean distances, which was in consonance with observed habitat fragmentation. The results of our study highlight that many corridors may still be functional as there is evidence of contemporary migration. Conservation efforts should provide legal status to corridors, use smart green infrastructure to mitigate development impacts, and restore habitats where connectivity has been lost. Source

Jhala Y.,Wildlife Institute of India | Qureshi Q.,Wildlife Institute of India | Gopal R.,National Tiger Conservation Authority
Journal of Applied Ecology | Year: 2011

Indices of abundance offer cost effective and rapid methods for estimating abundance of endangered species across large landscapes, yet their wide usage is controversial due to their potential of being biased. Here, we assess the utility of indices for the daunting task of estimating the abundance of the endangered tiger at landscape scales. 2.We use double sampling to estimate two indices of tiger abundance (encounters of pugmarks and scats per km searched) and calibrate those indices against contemporaneous estimates of tiger densities obtained using camera-trap mark-recapture (CTMR) at 21 sites (5185 km2) in Central and North India. We use simple and multiple weighted regressions to evaluate relationships between tiger density and indices. A model for estimating tiger density from indices was validated by Jackknife analysis and precision was assessed by correlating predicted tiger density with CTMR density. We conduct power analysis to estimate the ability of CTMR and of indices to detect changes in tiger density. 3.Tiger densities ranged between 0.25 and 19 tigers 100 km-2 were estimated with an average coefficient of variation of 13.2(SE 2.5)%. Tiger pugmark encounter rates explained 84% of the observed variability in tiger densities. After removal of an outlier (Corbett), square root transformed scat encounter rates explained 82% of the variation in tiger densities. 4.A model including pugmark and scat encounters explained 95% of the variation in tiger densities with good predictive ability (PRESS R2 = 0.99). Overall, CTMR could detect tiger density changes of >12% with 80% power at α = 0.3, while the index based model had 50% to 85% power to detect >30% declines. The power of indices to detect declines increased at high tiger densities. 5.Synthesis and applications. Indices of tiger abundance obtained from across varied habitats and a range of tiger densities could reliably estimate tiger abundance. Financial and temporal costs of estimating indices were 7% and 34% respectively, of those for CTMR. The models and methods presented herein have application in evaluation of the abundance of cryptic carnivores at landscape scales and form part of the protocol used by the Indian Government for evaluating the status of tigers. © 2010 The Authors. Journal of Applied Ecology © 2010 British Ecological Society. Source

Gopal R.,National Tiger Conservation Authority | Qureshi Q.,Wildlife Institute of India | Bhardwaj M.,Wildlife Institute of India | Jagadish Singh R.K.,Wildlife Institute of India | Jhala Y.V.,Wildlife Institute of India
ORYX | Year: 2010

We evaluated the status of tigers Panthera tigris and their prey in Panna Tiger Reserve using occupancy surveys, camera-trap mark-recapture population estimation, and distance sampling along foot transects, in 2006. Forest Range tiger occupancy in the Panna landscape (3,500 km2) estimated by 1,077 surveys of 5 km each was 29% SE 1. Within occupied Ranges of the Reserve a mean of 68% SE 7 of forest Beats had tiger signs. A total of 800 camera-trap nights yielded 24 captures of seven individual adult tigers within an effective trap area of 185.0 ± SE 15.8 km-2. The best model incorporating individual heterogeneity (Mh) estimated the tiger population to be 9 ± SE 2. Tiger density was 4.9 ± SE 1.5 per 100 km2 and was lower than that reported in 2002 (6.49 tigers per 100 km2). Both occupancy and density indicated a decline of the tiger population in the Reserve. Mean ungulate density was 42.4 ± SE 8.4 km-2 and comparable to other tiger reserves. Since our survey in 2006 tiger status in Panna has deteriorated further because of poaching. Panna was occupied by dacoits in late 2006 and anti-insurgent activities caused further disturbances. In late 2008 there was a single male tiger left in Panna but he has not been seen since January 2009. The Madhya Pradesh Forest department has reintroduced three tigers to Panna from neighbouring tiger reserves. Panna, along with Sariska Tiger Reserve, exemplifies the vulnerability of small, isolated tiger populations to local extinctions caused by poaching, even in areas with suitable habitat and sufficient prey. © 2010 Fauna & Flora International. Source

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