M Sc Dissertation(WII)
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Item Social Behaviour and Duetting in Hoolock Gibbons in Gibbon Wildlife Sanctuary, Assam(Wildlife Institute of India, Dehradun, 2009) Sankaran, Sumithra; Rawat, G.S.; Kumar, R.S.The hoolock gibbon (Hoolock hoolock), only anthropoid primate found in India, is a pair-living, territorial species, which duets extensively. Various hypotheses regarding the function of this behaviour in monogamous primates include territory advertisement, pair-bonding, mate defense, resource defence and group cohesion. This study aimed to understand the nature of social behaviour of this species, and how duetting fits into the repertoire of social behaviour seen in this animal. Three groups of Hoolock gibbons were habituated and studied intensively over a three month period. Relationships between the different group members were explored, alongside time budgets of various activities of the adult pair, the synchrony in their behaviour and frequency and nature of all affiliative and agonistic behaviours. Relationships between territory sizes, group sizes, frequency of duetting and nature of other social interactions have been examined in detail. A considerable amount of individual difference were found between the different study animals in their interactions with other group members. These animals display complex affiliative interactions with rare displays of aggression. It was found that although the proportion of time spent in social interactions was comparable between the three groups, the proportioning of this total time among different social interactions may vary considerably. The primary difference was found to be in allogrooming interactions with the proportion of time time spent increasing with increase in group size. The study also found considerable evidence for the possible existance of male-care in this species.Item Resource Tracking by Three Species of Hornbills in Rajaji National Park, Uttarakhand, India(Wildlife Institute of India, Dehradun, 2009) Warrier, Rekha; Ramesh, K.; Rawat, G.S.Resource tracking is the ability of organisms to adjust to variations in resource availability through numerical or functional responses. Numerical responses may be manifested, by changes in demographic processes or, through changes in movement patterns. Altered space use patterns can result in abundance fluctuations from the local to the landscape levels. An in-depth knowledge, of how resource fluctuations affect patterns of space use and abundance of a species can augment the conservation efforts which are underway for many species. Through this study, responses of three species of hornbills viz, Great Hornbill (Buceros bicornis), Oriental Pied Hornbill (Antharcoceros albirostris) and Indian Grey Hornbill (Ocyceros birostris), to the spatio-temporal variation in fruit abundances were studied in Chilla Range of Rajaj National Park, India. The study was carried out between December 2008 and April 2009, using a grid based occupancy framework and systematic sampling procedure. A total of 28, 1 km grid cells (spatial replicates) were sampled on nine occasions (temporal replicates) for quantifying hornbill responses to fruit abundance patterns. Fluctuations in fruit abundances were assessed by means of phenology transects, which were monitored once every month. Ecological Niche Factor Analysis was done to index the fig fruit availability by modelling fig tree distribution with Eco-geographic variables. Hornbill responses to fruit availability were analysed at two spatial (habitat types and fruit patch level) and temporal scales (winter and summer). Of the three species targeted, data could be consistently obtained only for Oriental pied hornbills. Great hornbills were rarely encountered and Indian grey hornbills were seen commonly only towards the end of the study period. Thus the detailed analysis focused only on Oriental pied hornbills. During the study, non fig fruit availability showed severe variations across areas, and over time. The month of March seemed to be the period of absolute non-fig fruit resource shortage. Figs, especially Ficus rumphii, were the only species that fruited and helped sustain the frugivore community during this period of scarcity. Thus, Ficus rumphii is a potential key stone species for the area. The bias corrected occupancy estimates revealed that Oriental pied hornbills frequented the forest types (Miscellaneous forest) that had high fruit availability in both seasons. At the patch level, intensity of grid use was positively correlated with abundance of non fig fruits in winter (r = 0.5, pItem Interaction of Kiang (Equus kiang) with Livestok in Hanley Valley of Chanthang Wildlife Sanctuary, Ladakh(Wildlife Institute of India, Dehradun, 2009) Hussain, Asif; Qureshi, Qamar; Rawat, G.S.Hanley Valley «320 41' 27" N 790 04' 3.5") in Eastern Ladakh forms the western most extension of Tibetan plateau and has been recognized as an important biogeographic province in India (Indian Trans-Himalaya). This region harbors a rich array of wild and domestic ungulates. The area is also home to nomadic Changpa and Tibetan refugee herders. The political, social and ecological transformations have altered previous, well-established links between the pastoral population and their rangeland environment. Over the years, with growing integration of the local economy of Ladakh and with better development of cash markets, the pastoral community is fast losing its tolerance towards the kiang and it is increasingly seen as a competitor to livestock. The purpose of this study was to document this intensifying conflict between pastoralism and Kiang conservation, using resource selection functions. Data on habitat variables were collected on 4 fixed trails of varying length (3- 7 km) for kiang (with and without livestock presence) and livestock for use availability analysis. For food habits, micro-histological method in case of kiang and bite count method in case of livestock was used. Data on activity pattern of kiang was collected to examine change in response to livestock presence. Density and encounter rates were estimated using vehicle transects (n=5) of varying lengths (5-56 km). Livestock were followed (focal animal sampling) from dawn to dusk to estimate amount of forage removed. Availability of different habitat variables was estimated using ArcGIS 9.2. Total of 104 kiang groups before arrival of livestock and 187 kiang groups after livestock arrival to the area were recorded. Habitat use by kiang and livestock was significantly different (8 = 0.00016, P < 0.05). Habitat use by kiang before and after livestock arrival was found to be significantly different (8 = 0.013, P <0.05). Groups of kiang were observed (n=14) for time budget evaluation, 7 prior (640 min) and 7 (820 min) after livestock had come to the area. Activity pattern of kiang before and after livestock arrival was found to be significantly different (8 = 0.04, P <0.05). Food preference for kiang before and after livestock arrival was not found to be significantly different. Food preference for kiang and livestock was significantly different (6= 0.0000007, P < 0.05). Use-availability analysis suggested differential selection for food plants. Schoener's niche overlap for food items found moderate overlap between kiang, sheep and goat «60%) and high overlap between kiang and horse (>80%). Forage removed (kg) by sheep, goat and horse were 2.33 kg, 2.25 and 8.19 kg respectively. Total density and encounter rate for Hanley valley was 0.07 kiang/km2 and 0.45 kiang per km respectively. The difference in habitat use translated into Kiang using higher elevations while livestock used middle elevations more than available. Kiang used steep slopes whereas livestock used steep as well as gentle slopes more than available. Kiang used North-West aspect more than available. Kiang used vegetation communities dominated by graminoides while sheep-goat used communities dominated by shrub and forbs. Density and encounter estimates did not show considerable increase in kiang population compared to previous studies. Hence, the perception of people of kiang overstocking in the study area appears to be misplaced. Detailed perception studies should be carried out in the whole of Changthang and herder-centered participatory programmes need to be carried out on a large scale to ensure long term conservation of kiang in eastern Ladakh.Item Patterns in plant species richness and diversity in the forest fragments of Western Ghats, Karnataka.(Wildlife Institute of India, Dehradun, 2007) Page, Navendu V.; Qureshi, Qamar; Rawat, G.S.Patterns of species richness diversity and distribution, and the factors affecting these patterns have always attracted the attention of many ecologists. Degree of fragmentation is one such factor affecting the species richness and composition also of great importance to conservation biology in light of rapid loss of biodiversity. The study examined the patterns of distribution and species richness and its correlates in a fragmented landscape in Kodagu district, Western Ghats, Karnataka. The study also examined some of the factors affecting distribution of epiphytes such as distribution along the tree height gradient and host specificity. A total of 129 species of trees, 29 species of Iians as and 68 species of vascular epiphytes were recorded in 56, 25m x 25m square plots. 60 species of shrubs were recorded in 90, 5m x 5m square plots. Patch area was found to be significantly correlated with tree species richness, but area was not correlated with shrub, liana and epiphyte species richness. However plant density used as measure of site specific productivity along with area were significantly correlated with lianas and epiphyte richness. Neither of these could explain the variation in shrub species richness. Lianas and shrubs did not show any such trend but epiphyte richness showed a negative trend in rarefied species richness with increase in area. Rank abundance curves indicated that Reserve forest had the most equitable distribution of abundance classes and also more number of rare species. Species composition was found to differ significantly across different size classes. All the plant communities showed moderate levels of nestedness. Distribution of an epiphyte along the tree was not influenced by the mode of dispersal alone. There was no strong evidence in support of host specificity however some selective host species were found to be favoured by epiphytes.Item Habitat use and food selection by wild and domestic ungulates in the Sikkim Transhimalaya.(Wildlife Institute of India, Dehradun, 2007) Chanchani, Pranav; Rawat, G.S.By defining a resource, determining the resources available to animals and sampling the array of resources actually used by an animal (Krebs 1999), it becomes possible to gauge the nature of interactions between species. This study explored aspects of resource use by diverse assemblage of wild and domestic herbivores including The Tibetan argali (Ovis ammon hodgsoni), Tibetan Gazelle (Procapra picticaudata), kiang (Equus kiang), blue sheep (Pseudois nayaur), domestic yak and sheep in a Trans-Himalayan environment during the lean winter period. Sampling was carried out in a systematic manner using trails, as well as by sampling opportunistically. To quantify vegetation, a 3.52 Ian grid was overlaid on an image of the study area, and grids were randomly picked from these for random sampling. A number of habitat and vegetation variables were measured or noted for all ungulate sightings or within vegetation sampling stations and these were used in analysis to ascertain patterns of habitat use and food selection. U sing a hierarchy of spatial scales, the study modeled animal distributions, and investigated the use of habitats and food habits of ungulates in relation to the availability of these resources in their environment. The study's major findings were that all ungulates were found to occur in the true Trans-Himalaya except for the blue sheep which selected more mountainous terrain in the transition zone between the greater and Trans-Himalaya .. Statistical tests of significance revealed that ungulates differed from one another or from random in their use of resources. Further, terrain features appeared to influence habitat selection to a greater-extent than vegetation. Finally, the findings of this research indicate that although the wild and domestic ungulates of this region all exist in relatively large numbers, they tend to vary in their use of habitats and food either by differences in their distribution, or in the selection of finer environmental (habitat and food) variables. The study therefore concludes that competitive inter-specific interactions are not very apparent in this region.Item Habitat use by Chital (Cervus axis) in Dhaulkhand, Rajaji National Park, India(Wildlife Institute of India, Dehradun, 1993) Bhat, Sridhar D.; Rawat, G.S.A study on the habitat use by chital or spotted deer (Cervus axis) was conducted in Dhaulkhand Rajaji National Park, from November 1992 to May 1993. The objectives of the study were to understand the spatio-temporal use of habitats by chital and to identify the factors that govern the patterns of habitat use. Foot transects were used to estimate the densities of chital and quantify the availability and utilization of resources.Item Habitat use by the Great Indian Rhinoceros (Rhinoceros unicornis) and the other sympatric large herbivores in Kaziranga National Park(Wildlife Institute of India, Dehradun, 2001) Banerjee, Gitanjali; Rawat, G.S.; Choudhury, B.C.A study on the habitat use by the Great One horned rhinoceros (Rhinoceros unicornis) and three other sympatric ungulates was carried out in Kaziranga National Park (KNP), Assam during December 2000 to April 2001. KNP supports more than half the world's population of the Indian Rhinoceros, a highly endangered species. Since this park also supports a high diversity and density of herbivores coexisting in a typical floodplain habitat, it was an ideal place to conduct the following study. The study aimed to determine how 4 large herbivore species rhino, wild buffalo, swamp deer and hog deer achieve spatial and temporal separation across two seasons. The study also investigated how nutritive content of the forage determines habitat selection by these species. KNP was an ideal place to study habitat use patterns by these four sympatric species due to the seasonal variation of forage quality caused by the practice of annual burning. Sampling for animal abundance within each habitat type over two seasons was done by monitoring transects. Feeding observations were obtained by scan sampling. Laboratory analysis was done to determine the nutritive content of the available forage during winter and summer. Seasonal and spatial differences observed in habitat occupancy patterns by the ungulate species within KNP seem to be a way of partitioning resources in order to minimize competition. During the winter season all ungulates selected the short grasslands for feeding. The wild buffalo and the swamp deer showed no variation in the habitat occupancy patterns showing a positive selection for the short grasslands. However, rhinos and hog deer were observed to prefer the tall, burnt and sprouting grasslands in summer for feeding during summer. When habitat occupancy patterns were correlated with the nutritive value of the forage it was found that all ungulates tracked high crude protein levels in available forage. Rhinos and hog deer formed an association that exploited areas that have high crude protein and low silica content. Wild buffaloes and swamp deer show less flexibility in habitat occupancy patterns and were observed to feed in short grasslands where there was a relatively high amount of crude protein available during both the seasons. The study revealed that crude protein played an important role in determining habitat use by hog deer, which shows a linear relationship with crude protein. Forage volume, an indicator of available food played a significant role in determining habitat use patterns for the large bodied ungulates, namely the rhino and the wild buffalo which is in keeping with their physiology and body requirements. There seems to be partitioning of space by the ungulates on the basis of body size and dietary separation. Rhino and hog deer were observed to formed one guild whereas wild buffalo and swamp deer formed another one. These two groups differed in the pattern of habitat occupancy suggesting that ecological separation in Kaziranga National Park, perhaps occurs on the basis of differential use of the habitat by ungulates that have a similar body size. There was an observed complementation of body sizes within each association. A large bodied ungulate associated with another ungulate that was much smaller in size. and therefore, had different ecological needs.Item Patterns in Species Composition and Distribution Among Vascular Epiphytes in Low-Lying Semi-Evergreen Forests of Arunachal Pradesh, India(Wildlife Institute of India, Dehradun, 2001) Padmawathe, R.; Rawat, G.S.; Krishnamurthy, JagdishThe patterns in epiphyte species composition and distribution in the low-lying semi evergreen forests was studied in Pakhui Wildlife Sanctuary and the adjacent Doimara Reserved Forests in western Arunachal Pradesh. Epiphyte community changes due to microclimate and host characteristics were studied by comparing sites of different microclimates namely riverbanks, tree fall gaps, closed forests and logged forests. Systematic sampling showed that epiphyte species diversity, increased marginally from low levels in the tree fall gaps to maximum levels in the riverbanks with intermediate levels in the logged forest and closed forest. There were dominance of certain families and life forms in different sites. Trends in epiphytic communities were closely related to changes in microclimate and host characters. The environmental variables were summarized by Principal Component Analysis, which yielded three components explaining 75.5% of the variance. Component one was positively correlated with temperature and canopy cover and light intensity in the horizontal zone, whereas relative humidity was negatively correlated. Component two was strongly correlated with vertical light intensities. Component three was purely a temperature factor . Araceae, Gesneriaceae and Asclepiadaceae correlated with vertical temperature humidity component while Orchidaceae and Moraceae were correlated with horizontal temperature. Families Aspleniaceae and Gesneriaceae were positively correlated with component one (qualitative parameters) of the vegetation characteristics, Therefore, epiphyte species richness were significantly different between across bark texture and architectural model of the host. Warty and wrinkled bark supported maximum species and Champagnats model of tree architecture supported higher number of epiphyte species. Six species were found only in the trunks and ten species confined themselves to branches. A total of twelve rare species of different families were found in the study area. The major implications of the study are the intimate relationship of epiphytes with diverse factors of climate and host characters, the change in one will trigger corresponding changes in other. Logging as a practice removes lot of trees, which reduces the diversity of substrate and microhabitat conditions available for epiphytes. It is important to maintain atleast a few big trees to serve as mother trees for recovery of the lost species.Item Effect of Habitat Alteration On Herpetofaunal Assemblages on Evergreen Forest in Mizoram, North-East India(Wildlife Institute of India, Dehradun, 1999) Choudhury, B.C.; Panwar, Samraat; Rawat, G.S.The response of frogs and Lizards to habitat alteration was studied in South Mizoram. Chronoseres were selected such that two successional gradient were represented- jhum fallows regenerating to mature forest. and jhum allows converted to teak plantations. Herpetofauna were sampled by three techniques- strip transects, pitfall trapping. and systematic searching. Species richness of herpetofauna increased along the jhum-mature forest gradient. However. teak plantation had a depauperate herpetofauna. similar in composition to the 1- year jhul1l fallows. All frogs and lizards were c1assilied into 6 guilds on the basis of their activity period (diurnal or nocturnal) along with whether they were terrestrial , arboreoterrestrial or arboreal. Analysis of the strip-transect data showed that there were distinct differences in the distribution and abundance patterns of diurnal and nocturnal species. To examine patterns, multidimensional scaling (MDS) was used for indirect gradient analysis in two ways- firstly to summarize differences between sites and secondly, to explore possible associations between herpetofaunal guilds and habitat parameters across categories. The MDS differentiated two different groups of habitat variables. One group makes up the gross structural components of the habitats. while the other represents microhabitat parameters. All guilds were more strongly associated with trends in microhabitat distribution. than macrohabitat-parameters. while species richness showed diffuse associations with habitat parameters. The assemblages in the I to 10 yr. jhum fallows and teak plantations were dominated by a set of terrestrial and arboreo-terrestrial lizard species. Most of those species are distributed widely. either in the Indian subcontinent. or further east and south. into South-east Asia. On the other hand. a number of frogs and some lizards were restricted to mature forest. Most of these species are restricted either to North-east India. or to the study area itself. and some are apparently hitherto undescribed species. The fact that so many narrowly distributed species were found in mature forest has obvious conservation implications. Overall. the results suggest that in a mosaic of habitats resulting from jhum-cultivation. even remnants of primary forest may be of immense importance for persistence and recolonization by mature forest herpetofauna. Teak plantations offer a very marginal habitat for a large set of herpetofauna. even after a long period of growth.Item Determinants of Butterfly Species Diversity : Plant Diversity, Foliage Height Diversity and Resource Richness Across Vegetation Types(Wildlife Institute of India, Dehradun, 1999) Kunte, Krushnamegh J. ; Rawat, G.S.MacArthur and MacArthur's (1961) theory of foliage height diversity, which was originally discussed as a determinant of bird species diversity, has been a strong concept describing the possible role of vegetation structure in deciding resource use, habitat selection and diversity of organisms. They measured foliage profile, and calculated foliage height diversity using information theory. Their results showed increase in foliage height diversity from simple to complex vegetation types, and bird species diversity was positively correlated with it. They then proposed an evolutionary mechanism to explain this correlation. A continuous flow of studies on vegetation structure and species diversity or habitat use of organisms followed after MacArthur and MacArthur (1961), but mostly they focused on birds. Subsequently, vegetation parameters other than foliage height diversity, such as horizontal vegetation heterogeneity or patchiness, also proved equally useful or better predictors of bird species diversity. Moreover, some studies revealed that foliage height diversity and bird species diversity were not correlated in a few cases. This brought forth a question whether or not foliage height diversity is a strong determinant of bird species diversity, or a frequent correlate of some other factor that has a strong influence on species diversity. To find out why in some cases MacArthur and MacArthur's (1961) theory did notexplain species diversity, I identified following assumptions in their theory, which were unstated in their paper: i)resources for a species are evenly dispersed within a horizontal vegetation layer, ii)resources are unevenly dispersed across the horizontal layers, iii)even for generalist species, the cost of switching over between layers is high, which would preclude switching over between layers, and iv)if the first three assumptions are true, then each horizontal layer of vegetation would have a different set of species, each layer adding a similar magnitude of diversity in more complex habitats. If these assumptions do not hold true for real biological communities, one would expect that foliage height diversity would not be a good predictor of species diversity in all situations. To test MacArthurs' assumptions and explore patterns of butterfly diversity across vegetation types, I studied butterflies at the Anamalais, southern Western Ghats, in southern India. I sampled foliage height diversity in vegetation plots and butterflies on count lines as well as all-aut-walks (opportunistic sampling), recorded body measurements of the butterflies, floral parameters of the plants on which the butterflies fed, and compiled information on larval and adult feeding plant resources. Using these data, I tested three possible degeminates of butterfly species diversity namely, foliage height diversity, 2.plant species diversity, and 3.resource richness in different vegetation types. This was probably the first attempt to analyse growth form-wise resource richness and utilisation by butterflies across vegetation types, in the light of foliage height diversity theory. Although the correlations between butterfly species diversity, plant species diversity and foliage height diversity were statistically significant, the butterfly species diversity was not perfectly correlated with these two determinants. Butterfly species diversity increased from grassland to deciduous forest, through shrub savannah and teak plantation, but was less in the mid-elevation evergreen forest as compared to the deciduous forest. Plant species diversity and foliage height diversity, on the other hand, increased from the grassland to the evergreen forest, with the deciduous forest falling before the evergreen forest. The resources for butterflies were not distributed in the vegetation types as assumed by MacArthur, and butterflies were not observed following the pattern of habitat or resource utilisation as predicted by the theory. As a result, foliage height and plant species diversity did not satisfactorily explain the butterfly species diversity. However, larval host plant and total plant resource richness correlated significantly and appropriately with the butterfly species diversity. Therefore resource richness seems to be an appropriate and better predictor, or at least a correlate, of butterfly species diversity in situations when other predictors may not be correlated with it. This study suggests that butterfly species diversity is dependent more on the resource diversity. However, foliage height diversity and plant species diversity need not be satisfactory surrogates for resource diversity in all situations. Therefore butterfly species diversity may vary independently of plant species and foliage height diversity. Another important result of this study was that even for butterflies, which are directly dependent on plants, the resource richness is not necessarily correlated with the plant species diversity. It means that butterflies selectively use certain plant resources more than other plant resources. I speculate that it would be underlying utilizable chemical diversity and "sociability" of plant resources used that would ultimately decide butterfly species diversity within a vegetation type. I define a "sociable host plant" as the one that supports many insect "guests". The butterfly assemblages using plant resources with maximum utilizable chemical diversity and sociability would be most diverse in the vegetation type supporting these sociable host plants. However, sociability of the utilizable plant species, and resultant butterfly diversity, may be independent of total plant species diversity or foliage height diversity in the vegetation type.