M Sc Dissertation(WII)
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Item Open to Invasion Patterns in Fruiting Phenology and Seed Dispersal of Lantana Camara Across Different Habitats in North India(Wildlife Institute of India, Dehradun, 2021) Taneja, Yukti; Page, Navendu, V.; Kumar, R.SureshLantana camara (hereafter, Lantana) is a fleshy-fruited alien invasive plant that spreads mainly through seed dispersal mediated by vertebrate frugivores. Lantana has low shade tolerance and is thus more abundant in relatively open habitats. While open habitats may facilitate better germination of seeds and growth of saplings and adults, the role of habitat type on its reproductive output (fruits) and seed dispersal remains largely unknown. Understanding this can help predict differential patterns of invasion in different habitats. In this study, I aimed to understand the influence of canopy cover and other drivers on fruiting phenology, visitation patterns of frugivores on Lantana and fruit removal of Lantana. I carried out this study in Shorea robusta- dominated. moist deciduous forest and grassland-shrubland mosaics in and around the Wildlife Institute of India (WII) campus in the Dehradun valley, Uttarakhand from August 2021 to December 2021. To determine the influence of canopy cover on fruiting phenology, I marked and monitored (every fortnight) 45 Lantana bushes across a gradient of canopy cover from late August. To determine the drivers of visitation patterns of frugivores on Lantana and the fruit removal rates of Lantana across habitats, I earned out focal plant watch on 80 Lantana bushes across a gradient of canopy cover. I used a generalized linear mixed model (GLMM) to test the effect of canopy cover and shrub volume on the fruit crop size of Lantana bushes monitored for phenology.Item RISK ASSESSMENT OF POTENTIALLY TOXIC ELEMENTS IN THE HABITAT, AND DIET OF SMOOTH-COATED OTTER (Lutrogale perspicillata) IN TUNGABHADRA OTTER CONSERVATION RESERVE (TOCR), KARNATAKA(Wildlife Institute of India, Dehradun, 2024) Ahmed K., Niyaz; Johnson, J.A.; Hussain, S.A.; Sah, RuchikaSmooth-coated otter (Lutrogale perspicillata), is a vital indicator species for freshwater ecosystems, playing a crucial role in maintaining ecological balance. Despite their essential place in the food web, they are always neglected compared to other terrestrial carnivores. This study explores the distribution, diet, and, ecotoxicological exposures to smooth-coated otters in Tungabhadra Otter Conservation Reserve, Karnataka. The study area, encompassing a 36km stretch of the Tungabhadra River (TOCR), is a unique habitat facing significant anthropogenic pressures, including mining activities and pollution, which threaten the local biodiversity and otter populations. The distribution of smooth-coated otters in TOCR was assessed through intensive sign surveys, revealing a clumped distribution pattern. Otter signs, including spraints, pugmarks, and grooming sites were dominant signs found in the landscape. Dietary analysis was examined by analysing the spraints (scat), using two methods frequency of occurrence method, and the score bulk estimate method revealing a predominantly piscivorous diet. The diet consisted of about 14 species out of which 69.53% is constituted of non–native fish species (Oreochromis mossambicus, Labeo rohita, Cyprinus carpio, and Cirrhinus cirrhosus). Ecotoxicological assessments were performed on water, sediment, fish, and spraint samples to evaluate the presence of potentially toxic elements (PTEs). While PTE concentrations in water and sediment were generally below harmful thresholds, their presence poses a long-term risk through bioaccumulation. Risk assessment indicated significant potential health risks from metals like mercury and arsenic, which could impact otter healItem Assessing the distribution and density of the Fishing Cat in Bhitarkanika mangroves of eastern India by(Wildlife Institute of India, Dehradun, 2024) Ashik, C.S.; Mukherjee, Shomita; Gopi, G.V.; Pandav, BivashIdentifying the areas of occurrence, population, and the factors affecting the species distribution is critical in conservation and management. The Fishing Cat (Prionailurus viverrinus), a smaller feline native to South and Southeast Asia, is globally vulnerable and adapted to wetland habitats, with a diet primarily consisting of fish. This makes Bhitarkanika, a mangrove ecosystem, an ideal habitat for the Fishing Cat. This study was conducted to estimate the species density, determine the factors affecting its distribution, and assess the effect of lunar illumination and tidal fluctuation on Fishing Cat activity. Despite known occurrences of Fishing Cats in this area, there has been no proper assessment of their population or other ecological studies. Camera traps were deployed in 109 grids, each covering 1km², across a total of 145 km², for 2878 trap nights. Camera trap locations are unbaited, with two cameras used to capture both flanks. Spatially explicit capture-recapture (SECR) was used to estimate the density, resulting in 0.6 ± 0.1 individuals per km². The abundance was also calculated, with an estimate of 99 ± 16 individuals. These density estimates from this study are close to recent high-density estimates for the species. The canopy cover, the width of the creek, canopy cover and the distance to the aquaculture farms significantly influenced the Fishing Cat habitat use, indicating the need for the conservation of natural mangrove habitats and regulation of aquafarms present near the forest. In contrast, the presence of Saltwater Crocodile showed a negative effect on the distribution of Fishing Cats. The Fishing Cats were more active during the brighter nights of the moon phase (μ= 266.783, r= 0.051, p< 0.01) due to better visual detection. The activity was influenced both by the tidal fluctuations in terms of food resources from waterbodies and it is further enhanced by the lunar illumination during the night. Pairwise non-parametric tests showed that the probability distributions of Fishing Cat activity under lunar illumination and tide fluctuation (D= 0.125, p-value = 0.9885 and D= 0.125, p-value= 0.9899) were similar, indicating minimal differences between each probability distribution. This study underscores the importance of protecting the mangrove habitat and controlling aquaculture expansion to ensure Fishing Cat survival in the Bhitarkanika National Park.Item Playing it Safe Tiger Movement and Livestock Depredation Patterns in Panna Tiger Reserve, Central India(Wildlife Institute of India, Dehradun, 2021) Mohan, Manu K.; Ramesh, K.; Sathyakumar, S.The movement of large carnivores in human-dominated landscapes is not uncommon anymore. While their presence is superficially tolerated or ignored, it is a consistent cause of concern to the people living in its proximity, due to competing interests in sharing of resources and direct threat to human lives. Carnivores incur energetic costs in the form of restricted activity and having to make spatial and temporal activity adjustments. Humans, on the other hand, face losses from livestock depredation and/or loss of lives. Depredation patterns of livestock by carnivores are associated with a variety of factors including habitat structure as well as movement patterns of carnivores in relation to anthropogenic and livestock activity. Hence, deducing movement patterns of the groups in conflict is an important step in understanding the dynamics of conflict patterns at fine scales. Supplemented by models to predict the probability of conflicts spatially which delineates conflict hotspots, site-specific mitigation measures could be devised. To understand such patterns of carnivore movement and relation to livestock depredation events, I conducted this study in a human-dominated region adjacent to the Critical Tiger Habitat of Panna Tiger Reserve in central India from December 2020 to April 2021, within an area of 200 km2. The broad objective was to model the conflict probability based on the proportion of the human-dominated area used by tigers, its intensity of use and spatio-temporal activity within the area, in response to human disturbances. For this, I used intensive camera trap sampling at fine-scale within grids (1 km x 1 km) across the entire study area. Movement parameters of tigers such as displacement and distance to villages in day and night were also analysed by monitoring two GPS-collared tigers in the study area. Occupancy estimates showed 74% of the sampled area being used by tigers, with the relative abundance of a large bodied wild prey (sambar) as the strongest predictor. In addition, a clear positive trend in the relative abundance index of tigers with distance to villages was observed. The temporal activities of the tigers also showed a significant difference in median activity time, shifting towards the night along with moderate diurnal activity at higher distances from villages. The tigers exhibited both crepuscular and nocturnal activity at close distances to villages. The movement range analyses of the tigers using camera traps showed the study area being used by 17 tigers, with 9 of them being adults (>3 years of age). Fixed Kernel Density home-range estimates of the two GPS-collared tigers showed a considerable proportion of their home range areas falling within village boundaries (10%) and an average of 16% of all GPS locations of the tigers fell within 0-100 metres from villages. Despite such high exploratory use of areas within and close distances to villages by sub-adults, there were relatively low incidences of conflict between the tigers and villagers in the study area. Finally, to assess the extent of risk and predict the probability of livestock depredation in the area, Generalized Linear Models were used. The best-fit model indicated a significant negative effect of distance to villages and highway to the probability of livestock depredation. Linear intrusions through highway and forest trails from villages allow easy access to livestock and herders for the utilization of the multi-use buffer areas of the Reserve as well as the tigers to come in proximity to settlements. Corralling of livestock in the night, avoiding free-ranging and grazing of livestock in the identified conflict hotspots, incentivization of alternate source of livelihood by strengthening the institutions such as Eco-Development Committees, along with continuous monitoring of tigers which range close to human settlements are discussed as some of the important measures which can be adopted to decrease the interfaces leading to tiger-human conflict in Panna Tiger Reserve.Item Assessment of Swamp Deer Habitat in Pilibhit Habitat Block Uttar Pradesh(Wildlife Institute of India, Dehradun, 2021) Singh, Lovepreet; Mondol, Samrat; Pandav, BivashThe study was carried out in terai region of Uttar Pradesh covering the Pilibhit Tiger Reserve (PTR) and those areas of North Kheri Forest Division (NKFD) which fall between Pilibhit TR and Kishanpur Wildlife SanctuaryItem Niche partitioning between assamese and rhesus macaque in the Askot landscape of Uttarakhand, Northern India(Wildlife Institute of India, Dehradun, 2017) Justa, Priyanka; Kumar, R.S.; Talukdar, GautamClosely related species often have similar requirements and these species need to have certain ecological adaptations to live in sympatry. Two congeneric species the Assamese (Macaca assamensis) and the rhesus macaque (Macaca mulatta) co-occurring in the Askot landscape of Uttarakhand were studied to understand the mechanisms allowing their coexistence. 2. Ecological niche differentiation for the two species was investigated by examining three possible modes of separation: activity pattern, diet and spatial use following observational protocols over a period of five months (December 2016-April 2017). Crop-raiding by macaques often results in human-macaque conflict. With the help of semi-structured interviews, attempts were made to access the level of conflict and people’s perception of these two macaque species. 3. Limited niche overlap was found between two primate species across the study duration. The Assamese macaque differed from the rhesus macaque in time spent on various activities. The former spent more time feeding and the latter in resting. Although 44% of all food items were consumed by both the species, only three of the ten major food items were shared. Assamese macaques preferred leaves and had broader niche breadth compared to rhesus macaques who fed more selectively on fruits. There was a significant difference in feeding heights, habitat and roosting site preferences of the two species. Differences in diet choice and roosting sites, in turn, resulted in differences in daily movement and home range of these species. Despite a partial home range overlap, both these species were found to be spatially segregated at a local scale. 4. The extent of niche overlap across winter and spring seasons in the area showed the greatest divergence in the diets of the two species in winter, while diet overlap was more pronounced in spring. As resources were abundant in the spring, an increase in niche overlap may not have lead to competitive interactions. Synthesis and application: Knowledge about differential resource use of macaques might help in assigning conservation priorities to the different species and their specific ecological niches along with designing species-specific management strategies. The study was able to distinguish the macaque's tendency to co-exist with humans.Item Riverine Habitats Under Changing Land-use : A Resource Selection Study of Smooth-Coated Otter (Lutrogale perspicillata Geoffroy Saint-Hilaire 1826) in Kabini River and Tributaries(Wildlife Institute of India, Dehradun, 2015) Aneesh, C.R.; Hussain, S.A.; Johnson, J.A.; Talukdar, G.Habitat selection is an important part of the ecology of semi-aquatic mammals since they are highly specialized animals. River otters are especially vulnerable animals in the present situation due to increasing human disturbance, altering riparian vegetation damming and channelization in river basins. This study looked at the effect of land-use pattern on the habitat selection by otters with special reference to smooth-coated otter (Lutrogale perspicillata) in Kabini river, South India. The study showed fewer presence sites of smooth-coated otter inside the protected areas, due to naturally unsuitable habitats for the species, with shallower stream habitats in hilly terrains. These sites were occupied by Asian small-clawed otters (Aonyx cinerea). However the sign intensity was more in presence locations inside protected area and least in urbanized area. The detailed study in presence only sites revealed that anthropogenic disturbance primarily increasing human presence, fishing and grazing is the most important factor affecting selection of habitat by smooth-coated otter. The intensity of usage of habitat is also governed by disturbance factors. Other environmental factors are only secondary to disturbance factors affecting habitat selection which includes a set of factors pertaining to land and water summarized as slow, deep waters with intact bank cover and/or grassy banks with close escape cover distance. Prey fish species of medium size class (21-40cm) affects the habitat selection. Although Asian small-clawed otter and smooth-coated otter occur in same river system , there is a clear niche partitioning between these two species. The study also Looked at the effect of dams on otters which is the primary factor negatively affecting otter habitats. Yet flow regimes are mostly compensated due to more streams joining the main river channel. Increasing degree of habitat disturbance in different land-uses seems to negatively influence the fluvial functionality which is positively associated with otter habitat. The combined effect of isolation due to reservoir and increasing disturbances in downstream area pushes smooth-coated otters to select habitats upstream that are marginal to them and more suitable for small-clawed otters.Item Responses Shown by Bird Communities to Teak Palatations in Sagar Forest Division, Karnataka(Wildlife Institute of India, Dehradun, 2009) Barve, Sahas S.; Mohan, D.; Qureshi, QamarThis study was aimed at discerning the responses shown by bird communities to teak plantations of various age classes in Sagar Forest Division, Karnataka within Latitude 13° 36' and 14° 38' North 74° Longitude 38' and 75° 32'East Latitude. Birds were sampled using line transects in three habitat strata, natural plantations, mature teak plantations and young teak plantations. Density, diversity and community similarity were the chief ecological responses that were quantified to bring out differences in the usage of forest plantations by native bird fauna. Habitat (vegetation) correlates, both structural and floristic were quantified to establish the reasons for differences. The sampling period was from December 2008 to April 2009. This period was divided into two seasons, winter and summer. A total of 9 transects were laid, marked and sampled at least 4 times per season. Birds were divided into three feeding guilds and three habitat guilds for analysis. The overall density of birds across the three strata was found to be higher in summer than in winter. However a guild level analysis showed that in winter while insectivorous birds were most abundant in natural forest with decreasing density towards young plantations (F (6.241) , p< 0.05). There was no difference in their density in summer. Phytophagous birds showed the exact reverse trend. Density of this guild was higher in young plantations than natural forests and mature plantations in winter and summer (F(S.689), p< 0.05), (F (14.302), p< 0.01) respectively. Overall diversity of birds showed a trend of decreasing species richness from natural forests to young plantations in both seasons. However this difference was almost non existent in summer at the guild level. The abundance of birds belonging to evergreen and moist deciduous forests shows a consistent· rise in abundance from winter to summer in all the three strata. There is also evidence that there is ingression of individuals of species that were common to both seasons possibly for nesting. The overall community similarity is quite high between the three strata and it increases from winter to summer. Bird diversity was found to be affected by the vertical spread of vegetation and tree height heterogeneity (R=0.871, pItem Habitat Use by Rodents in a Sandy Habitat Around Sam, Western Rajasthan(Wildlife Institute of India, Dehradun, 1999) Mukherjee, Shomen; Goyal, S.P.Earlier studies on rodents in the Thar have recorded only the broad habitat types in which the different species occur. Except Rogovin el al. (1994), no other study has looked into microhabitat use by rodents. The present study aims to look at habitat use by three species of gerbils in a sandy habitat: The macro and microhabitat use by three species of rodents viz. Gerbillus gleadowi, G.nanus and Meriones hurrianae, in a sandy habitat, receiving rainfall of around 100-200 mm, was studied in Thar desert. Three distinct sandy habitats (Stabilized dunes Barren dune and Interdune), within 4 sq. km. area around Sam, Jaisalmer. was selected for the study. Due to zero captures after 500 trap nights, the use of Sherman traps was discontinued. Instead, circular track plots made out of chalk powder were used for looking at microhabitat use within each of the habitats. Track identification, up to species level, was first standardized from live specimens in captivity and then used in field. A total of sixteen variables representing habitat complexity (vertical), heterogeneity (horizontal) and phenology were enumerated around each plots. G. gleadowi was found to be the most abundant species, occupying all the three habitats. G. nanus was found to inhabit the Stabilised and Interdunal areas, while M. hurrianae was present only in the Interdune. Factor analysis using principle component extraction was used to determine the microhabitat characteristics. G. gleadowi was the sole occupant of Barren dune, where it did not show preference for any particular microhabitat. ' During winter, in Stabilised and Interdune, G. gleadowi was found using areas with relatively less compact soil, lower mean vegetation height and fewer number of hummocks compared to G. nanus. In summer, the species still continued using areas with relatively lower soil compactness, mean vegetation height and fewer hummocks compared to G. nanus, but showed higher use of areas with more ground cover (vegetation) compared to winter. G. nanus was found using areas with relatively more compact soil, higher mean vegetation height and greater number of hummocks. Overall, G. gleadowi was found to use the maximum range of microhabitats compared to the other two species. The summer niche space of G. gleadowi was found to be greater than its winter niche. During summer it was found using areas with more ground cover, higher percentage mature leaves, young leaves and fruits. M hurrianae was found to have a strict association with Capparis decidua tree, under which it burrows. The species is probably facing microhabitat loss due to collection of C. decidua poles by villagers.