Theses and Dissertations
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Item Interactions between forage, recruitment and activity patterns of Blackbuck (Antelope cervicapra)(Wildlife Institute of India, 2005) Priyadarshini, K.V.R.; Jhala, Y.V.In this study based on the seasonality of blackbuck calving in VNP and examined whether birth synchrony exists in this population. I assessed the seasonal patterns in forage vailability, quality, and body condition of blackbuck females, and examined if changes in forage availability, quality and body condition of females influenced calving seasonality. · Forage variables that were measured are, aboveground grass biomass, moisture, crude protein, ADF, lignins, and silica content in grasses. Some of the forage variables showed considerable seasonal changes, while some did not. Biomass was the highest in the cold and late wet seasons and lowest in the dry season. Crude protein content was the highest in wet season and the lowest in dry season. Blackbuck in VNP appear to have a cyclical calving pattern. The dry season calving peak was probably timed to the impending peak in forage quality, which would have benefited the calves when they weaned. The wet season calving peak occurred after a gap that corresponded to inter-calving interval in blackbuck. The females that calved in the wet season perhaps provided greater maternal nutritional investment into the young, which might have compensated for the lower quality forage that was available to the calves when they weaned. In this study based on the seasonality of blackbuck calving in VNP and examined whether birth synchrony exists in this population. I assessed the seasonal patterns in forage availability, quality, and body condition of blackbuck females, and examined if changes in forage availability, quality and body condition of females influenced calving seasonality.· Forage variables that were measured are, aboveground grass biomass, moisture, crude protein, ADF, lignins, and silica content in grasses. Some of the forage variables showed considerable seasonal changes, while some did not. Biomass was the highest in the cold and late wet seasons and lowest in the dry season. Crude protein content was the highest in wet season and the lowest in dry season. Blackbuck in VNP appear to have a cyclical calving pattern. The dry season calving peak was probably timed to the impending peak in forage quality, which would have benefited the calves when they weaned. The wet season calving peak occurred after a gap that corresponded to inter-calving interval in blackbuck. The females that calved in the wet season perhaps provided greater maternal nutritional investment into the young, which might have compensated for the lower quality forage that was available to the calves when they weaned.Item Resource Selection By Large Herbivores with Special Reference to Blackbuck (Antilope cervicapra) in Point Calimere Wildlife Sanctuary, Tamil Nadu(Wildlife Institute of India, Dehradun, 2013) Jabaraj, Frank Sadrack D.Most of the wildlife habitats in India are shared by a number of ungulate species. This encompasses both wild and domestic ungulates. In areas, where both domestic and wild ungulates co-occur, it is essential to understand the ecological interactions among them so as to better manage the habitat and wild species. Competition between livestock and wild herbivores has remained contentious and it has remained as major a conservation issue for native ungulates. This work aimed to investigate the resource selection by wild (Blackbuck and Chital) and domestic ungulates (Feral horse and Cattle) with special emphasis on Black Buck in Point Calimere Wildlife Sanctuary in Tamil Nadu. The Black buck Antilope cervicapra Linnaeus (1758) is a grazer that is listed as near threatened species (IUCN Red list, 2012) and has been accorded the Schedule I status by the Indian Wildlife Protection Act, 1972. Black buck numbers in India have come down intensely in the last century and this antelope is currently restricted to small and scattered populations. Hunting and loss of suitable habitat are considered to be principal factors for the reduction in numbers. The present study deals with estimating the abundance and density of the wild and domestic ungulates using distance sampling and to determine the food habits and habitat use of these ungulates in the coastal landscape of Point Calimere wildlife Sanctuary, Tamil Nadu. The study was conducted from December 2012 to April 2013. Population densities of four sympatric ungulates in Point Calimere Wildlife Sanctuary, Tamil Nadu, was estimated using Distance sampling under line transect technique between January and April 2013. A total of eight line transects were laid with the total length 14.8 km, covering three habitats- Grassland, Mudflat and Tropical Dry Evergreen Forest (TDEF). Each transect varied in length from 1.5 to 2 km and was walked thrice in each month. A total of 628 sightings of the target species were recorded in the line transects (n= 458 black buck, n=S8 chital, n=50 feral horses and n=62 cattle). The total effort was 177.6 km(grassland- 57.6 km, Mudflat-26 km and TDEF -96 km}. The estimated density {number of individuals per km2± SE} of blackbuck was 37.1 ± 5.2 with group density of 9.6 ± 3.1, chital was 4.5 ± 0.9 with group density of 2.7 ±0.5, feral horse was 7.6 ± 1.2 with group density of 3.3 ±0.3 and cattle was 21.9 ± 3.3 with group density of 2.5± 0.4. Adult sex ratio (Male: Female) of blackbuck was 12.5 Male/100 Female, and for chital it was 25 Male/ 100 Female. The Female: Fawn ratio of blackbuck was 24.2 Fawn/100 Female and for chital it was 21 Fawn/100 Female. Most ungulates show a temporal diet variation between monocot and dicot dominated diets. This study investigated the habitat use and diet overlap between wild ungulates (blackbuck, chital), domestic livestock (Brahmini cattle) and feral horse at Point Calimere Wildlife Sanctuary, Tamil Nadu during January 2013 to April 2013. The assumption of the study was that black buck has high degree of food and habitat overlap with other sympatric ungulates in the study area. The food habits and diet overlap of ungulates were estimated using feeding site method (Lovaas, 1958). The line transects that are laid for estimating the densities of the herbivores were used for studying the ungulate- habitat interactions. Two types of analysis were used for the assessment of habitat use, one- way analysis of variance {AN OVA) and multiple regression analysis. Levin's measure of Niche breadth showed highest for feral horse (O.89), followed by cattle (0.72), blackbuck (0.48) and lowest for chital (0.26). Pianka's index (Pianka 1973) showed high diet overlap between blackbuck and cattle (95 %) followed by blackbuck and feral horse {81 %}, blackbuck and chital (38.1%) and cattle and feral horse (91.3%). Forty three forage species were identified to be eaten by all target species out of which blackbuck utilized 23 foodplants, chital 33, cattle 29 and feral horse 35 food plants. The nutrient analysis of the food plants eaten by the sympatric ungulates was done and with respect to blackbuck, multiple regression analysis was done for the 23 plant species it has fed. The result showed that blackbuck did not show any significant difference towards nutrient contents of the utilized food plants. Dung/pellet analysis revealed that all the four species utilized monocots (graminoids) in high proportion where blackbuck utilized 82.12%, chital 74.63%, cattle 85.7% and feral horse 84.9%.The observed high competition for the available food resources especially for graminoids by the domestic livestock and feral horses is a matter of concern. Creation of Livestock- free areas is necessary for the conservation of blackbuck in the Sanctuary.Item Ranging, Activity Patterns and Habitat Use of Blackbuck and Nilgai in Velavadar National Park, Gujarat, India(Wildlife Institute of India, Dehradun, 2001) Sahabandhu, H. Dhanushki R.; Chellam, Ravi; Mathur, V.B.I studied the activity patterns, ranging and habitat use of blackbuck (Antelope cervicapra rajputanae) and nilgai (Boselaphus tragocamelus) in Velavadar National Park from November 2000 to April 2001. Scan sampling was used to record blackbuck and nilgai activity patterns. Herds were also followed from sunrise to sunset to study the diurnal movements. Satellite imagery was used for vegetation mapping. Habitat availability and usage of both species were examined by plotting the grazing circuit on the satellite imagery. Activity patterns were found to differ amongst the various social groups, habitats and seasons. Temporal variations in foraging time and resting time were found in all the groups studied. Blackbuck had three foraging peaks and two resting peaks as compared to nilgai, which had two, and one peaks respectively. Diurnal distances were not found to differ in any of the different blackbuck or nilgai groups or between the two species. Differences between blackbuck herds in different seasons and habitats were attributed to the nutritional levels and the spatial dispersion of vegetation. Foraging behaviour decreased in summer supporting results of previous studies that blackbuck reduced foraging due to lower nutrition levels. Male blackbuck was found to forage 67% compared to 58% by females. This difference was attributed to larger body size in males, and the upcoming rutting/lekking season. No difference was found between nilgai males and females, except usage by females was slightly more in high nutritional areas. Female nilgai were found to become more selective in summer, by increasing their foraging time from 43% to 55%. But no difference in habitat usage was found, possibly due to sustenance from Prosopis juliflora pods. Blackbuck were found to spend more time foraging (53%) compared to nilgai (43%). This was due to blackbuck being more selective in the prevailing drought conditions, while nilgai were possibly supplementing their diet with P Juliflora pods. Differences between the two species in temporal allocation of foraging time was found which was ascribed to difference in gut capacity. No seasonal differences were found between the two species, except that nilgai were found to be using high nutrition areas. Nilgai were found to be more selective nutritionally than blackbuck, possibly due to nilgai being an intermediate feeder compared to blackbuck, which are coarse bulk feeders.Item Food Resource Partitioning Among Sympatric Bovids Chinkara, Blackbuck and Nilgai in Rajasthan Desert(Wildlife Institute of India, Dehradun, 1989) Kunhunu, N.V.Ashraf; Goyal, S.P.Patterns of dietary selection, overlap and spatial distribution were investigated for three species of sympatric wild ungulates and four species of domestic ungulates (goat, sheep, camel and cattle> during four seasons (summer, pre monsoon, monsoon & post monsoon) in Rajasthan desert. The objective was to determine the mechanisms of food resource partitioning among these seven species of ungulates and the factors allowing their coexistence. Two study areas, Dhawa-Doli and Janwar-Doli were selected for the study, based on the density and distribution of the three wild ungulates. More emphasis was given to Dhawa-Doli where two of the three species (chinkara & blackbuck> were common. Food habits were studied by direct observations. Feeding activity was recorded for feeding height, plant species and part eaten. Availability was determined by percentage cover classes. Three major vegetation zones were identified at Dhawa-Doli. Six study sites were selected across the three vegetation zones. Blackbuck were primarily grazers in monsoon when crops were beginning to grow and annual plants were abundant. Chinkara and nilgai browsed throughout the study and did not show any preference for monocots in periods of resource abundance (monsoon and post monsoon). Food habits of wild ungulates differed more between zones in summer and pre monsoon, when resources were limiting and the effect of vegetation zonation on food habits was evident. In monsoon and post monsoon when resources were abundant, the effect of vegetation zonation was negligible as opportunity for selection increased. Though dietary similarity was more in terms of plant species eaten between chinkara and goats and between sheep and blackbuck, they differed greatly in proportion of utilization. Greater overlap between chinkara and blackbuck during premonsoon suggest a possible temporary interspeciflc competition. In scrublands, dietary overlap was more between species with similar feeding strateg1es (goat & chinkara - sheep & blackbuck) and was less between species with dissimilar feeding strategies. Nilgai was spatially separated in summer and pre monsoon and showed a seasonal spatial overlap w1th chinkara and blackbuck at Dhawa-Doli during crop season. While blackbuck and nilgai exhibited a spatial divergence in response to temporal and spatial availab1lity of food resources, chinkara was largely sedentary. Though utilization of different habitat subun1ts (crop fields, cultivated fields and scrublands) were largely determined by the amount of disturbance, ch1nkara showed a random utilization of these subunits. Blackbuck showed a slight avoidance for crop fields, at least at day time, even though they consumed more crops than chinkara. Mean feeding height for domestic ungulates decreased towards post monsoon as they spent more time feeding on annuals. However, the mean feeding height for wild ungulates increased in response to the growth form of plants. The difference in utilization of different foraging strata was more evident between browsers and more similar between grazers. Broadly, this study suggests that dietary differences among all species were more important than spatial differences, in food resource partitioning.