M Sc Dissertation(WII)
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Item Impact of Habitat Fragmentation on Plant -Frugivore Interactions in Lowland Tropical Forests of Upper-Assam North East(Wildlife Institute of India, Dehradun, 2019) Jain, Abir; Page, Navendu; Rawat, G.S.Tropical forests are considered the storehouse of biodiversity. One of the key ecosystem processes that governs the diversity of tropical trees is seed dispersal. Tropical forests globally face deleterious effects of habitat fragmentation such as loss of habitat area, reduced species richness and altered community composition. Forest fragmentation can also alter mutualistic interactions between plants and seed dispersers, disrupting key ecosystem processes like seed recruitment and regeneration. In the past century, logging, habitat conversion to tea plantations and agricultural fields have resulted in the fragmentation of the last remaining lowland tropical forests of Upper Assam in north-east India. However, these isolated forest fragments might also hold a great potential to preserve native biodiversity distributed across patches. There is paucity of information on impacts of habitat fragmentation on plant–seed disperser interactions from Asia. 2. In this study, I investigate the impacts of habitat fragmentation on plant-disperser communities. The impacts were assessed at the level of the community and at the level of species guilds (body size, habits, and families). 3. The plant-frugivore interactions were recorded by systematically walking 27 trails across two habitat categories: contiguous forest sites (n=2) and fragmented sites (n=4) over the duration of four months. Spot census was carried out to record interactions between a fruiting plant and frugivores. Fruit handling behaviour of birds and fruit crop size of plants were also recorded. Plants and seed dispersers that interact with one another, forms a network. 4. I constructed presence-absence networks for each habitat type, which represents all plant-seed disperser interactions recorded in the contiguous forests and the forest fragments. ‘Network-level’ properties were obtained to understand the influence of fragmentation on plant-seed disperser communities and ‘Species-level’ properties were obtained to assess the roles of species guilds in each of these communities. 5. Although, the networks for contiguous and fragmented forests were similar in terms of total number of mutualist species participating in its organisation, their composition was different. On an average, frugivores had one plant partner more in the contiguous forest, while plants had three frugivore partners more in the forest fragments.Item Assessing the Impacts of Livestock-Induced Disturbance on the Vegetation Composition and Forest Regeneration of Sikkim's Mid-Elevation Forests(Wildlife Institute of India, Dehradun, 2019) Luxom, Nisam Mang; Rawat, G.S.; Sathyakumar, S.1. Livestock rearing earlier contributed sizeably to Sikkim’s economy, thus putting immense pressure on natural forests, which were converted into artificial pastures. These forests have not been subjected to evolutionary grazing pressure and differ in their sensitivity to the effects of livestock grazing, as compared to the historically-grazed tropical grasslands and rangelands. 2. This study aims to assess the impacts of livestock-induced disturbance on the vegetation and forest regeneration of the Sikkim Himalayan mid-elevation forests. 3. We sampled vegetation in and around pastures under different levels of livestock grazing pressure - from currently grazed to abandoned; and from heavily grazed to lightly grazed. 4. We found highest species richness and diversity values in abandoned pastures, as compared to areas which are currently grazed as well as areas which have not had a historical pasture presence. We found highest species richness and diversity values in abandoned pastures, as compared to areas which are currently grazed as well as areas which have not had a historical pasture presence. 5. We found significant difference between plant species composition among various livestock grazing levels. Species composition differed due to (1) grazing-tolerant herbaceous species, and (2) encroaching shrub or bamboo at the pasture boundaries in the absence of livestock as a control. 6. Seedling densities were overall lower in actively grazed pastures than in abandoned pastures. Seedling densities for buffer forested areas of the different livestock grazing levels were comparable, apart from the lightly grazed treatment, which had very low seedling densities. Sapling densities was higher in and around lightly grazed pastures, than the other livestock grazing levels; this contradicts the trend seen in seedling densities. 7. Seedlings and saplings in lightly grazed areas were from the same species pool; we propose that the decrease in the former and the increase in the latter’s densities is due to successful recruitment of the seedlings to the sapling stage. 8. Livestock grazing level, slope, shrub volume and position of plot (either within the pasture area or in the buffer forested area) explained seedling density. Seedling densities were highest in abandoned pastures, low in areas with high slope values, low in areas with high shrub volume and higher in buffer forested areas, compared to pastures. 9. Livestock grazing levels, slope value, shrub volume and position of sapling (wither in buffer forested areas or pasture areas) influenced sapling densities 10. Areas with and without active livestock grazing had similar proportions of unpalatable – palatable species; suggesting that direct herbivory may not be an important regulation by which density of regenerating is affected. Instead, other indirect livestock-related impacts, such as trampling or dung deposition, could lead to changes in regeneration metrics. 11. Successful regeneration occurs across the different livestock grazing levels, however the composition of regenerating species differs. Restoration of disturbed forests by artificial regeneration may not be required, as it may interfere with natural successional dynamics already in motion.Item Effects of Land Use Practices on Diversity and Abundance of Honey Bee Forage Plants in Senapati District, Manipur(Wildlife Institute of India, Dehradun, 2015) Ziipoa, Benjamin; Rawat, G.S.; Talukdar, G,S.; Gopi, G.V.North-east India, a global biodiversity hotspot, ·is also known for diverse socio-cultural and land use practices. One of the important cultural practices in a few pocket-s is bee keeping and honey production as a means of livelihood. However, there is a growing concern that with shortening of shifting cultivation cycle and frequent forest fire the diversity of bee forage plants· as well as honey production is declining in the region. Therefore, a study on the diversity of bee forage plants and bee keeping practices was conducted across various land use practices in Purul subdivision of Manipur, North-east India. The objectives of the study were: (i) To quantify the diversity and abundance bee forage plants in different land use land cover types, (ii) To document the honey bee abundance with respect to forage plant availability, bee keeping practices and traditional knowledge among the local bee keepers pertaining to bee keeping. The study was conducted during December April 2015 in Purul and Paomata subdivision of senapati, district, Manipur. The study area was stratified into five land use and land cover (LULC) types: (i) Semi-evergreen (primary) Forests above 1800 m asl; (ii) Moist Deciduous (Open Mixed) Forests between 1200- 1800 m asl; (iii) Secondary forests (Old Thurn Fallows between 1000 - 170q m; (iv) Secondary scrub (Young Thurn Fallows); and (v) Home Gardens and Agricultural Fields. Six trails of 2 km each were laid in various strata. AIthough each trail ten m radius plots were laid to quantify tree species abundance; concentric 5 m radius plots for shrubs and climbers; and four 0.5 m radius circular plots for herbaceous species. Direct and indirect signs of bee nests and locations of bee boxes were recorded. 30 professional bee keepers were interviewed for their knowledge on bee keeping and bee forage plants. Data were analysed following standard phytosociological techniques. Relationship between bee forage plants and bee abundance were established using R3.02 Generalized Linear Model (GLM). A total of 272 species of bee forage plants belonging to 105 genera and 92 families were recorded in the study area. Of these, 84 species were flowering during winter season. The number of flowering bee forage plants increased to 112 during spring season. It was noted that at least 25 species of flowering plants flower almost during all the seasons providing either nectar or pollens to the bees and other insect pollinators. Asteraceae, Rosaceae, Fabaceae, Brassicaceae and Malvaceae were the most dominant species available as bee forage plants, especially in and ar01md home gardens, backyards and cultivable waste. These species were very low in abundance in natural forests. However, Rosaceae and Fabaceae were more Common in Secondary Forests and Old Jhum Fields. Very few species of bee forage plants were flowering in Semi-evergreen Forests during winter seasons. Highest diversity of trees was recorded in semi-evergreen forests followed by Moist Deciduous Forest, Old Jhum Fallow and Young Jhum Fallow. However, overall density was highest in Moist Deciduous Forest. Budleja asiatica, Rubus ellipticus, Pyrlls pahsia, Engelhardtia spicata, Prunus cerasioides, Docynai india were the most widely available flowering species during winter and spring. These species were mostly found in open (Moist Deciduous), Old Jhum Fallows and closer to human habitation. Their frequency, density and distribution pattern has been compared across various land uses. The results revealed that settled agriculture with adequate cover of primary and secondary forests in vicinity coupled with plenty of ornamental plants and vegetables are best land use practices for honey production as well as enriching the pollinator diversity in the area. Short Jhum cycles and resultant frequent fires are detrimental to bees as well as bee forage plants. Pattern of bee distribution, local knowledge on bee keeping and conservation practices in relation to land use practices have been presented and discussed.Item Population Structure and Microhabitat Preference of the Himalayan Yew (Taxus wallichiana. Zucc) in Uttarkashi(Wildlife Institute of India, Dehradun, 2011) Ganguly, Rhea; Rawat, G.S.; Talukdar, GautamUnderstanding choices made by any species at a micro level is intrinsic to detecting patterns in ecological space. On the other hand, understanding how variations in micro site in turn affect the populations of any species is important in terms of ecological time. This study compares population structure of Taxus wallichiana. Zucc, a threatened medicinal tree endemic to Himalaya, across different habitat types and to studies micro site preferences (over space) exhibited by the species. The study maps the distribution of Taxus encountered and based on it, predicts areas which are likely to have Taxus. It also studies how differences in habitats affect the population structure of the species. Using generalized linear models, the microhabitat preferences of the species was modeled. This study is merely the preliminary to further insights to the species choices for a habitat and responses to habitat changes. The findings of the study are as below: 1. Population structure revealed significant differences between age class structure across habitat types (pItem Pastoral Practice and Herders Attitude Towards Wildlife in South Gobi Mongolia(Wildlife Institute of India, Dehradun, 2011) Mijiddorj, Tserennadmid; Rawat, G.S.; Badola, RuchiThis study deals with analysis of traditional and current pastoral practices in south Gobi areas of Mongolia with emphasis on herders' attitude towards wildlife. The study was conducted during December 2010 to May 2011. The major objectives of the study were to study: (i) Nomadic herders' pastoral practices and drives of changes. (ii) Influence of pastoral practices on human-wildlife conflict and (iii) nomadic herders' attitude towards wildlife. I used questionnaire surveys in two villages in Gurvantes soum to find out the past and current patters of herding, herders' attitudes and major drivers of changes. The villages were selected based on the fact that in one village (Tost), Snow Leopard Conservation initiatives are going along with livestock insurance and research programs, while in another village (Baysah) no conservation initiatives have been undertaken. However the range use patterns by the local herders and the level of conflict with wild carnivores is the same in both areas. A total of 144 individuals from different age, gender and educational background were interviewed, 74 in 8 aysah (nonconservation) area and 70 from Tost area where snow leopard conservation activities are taking place. The data were analyzed using SPSS Statistical Package for Social Sciences (SPSS) PC version 16.0 for . Generalized linear model GLM linear and negative binomial with log linear model. The study reveals that the pastoral practices among the herders in the study area is largely influenced by land tenure, mining disorder, school kids' admissions and development factors. Assessment of pastoral practice changes revealed that 84.7% herders had highly altered their seasonal movement pattern which can affect pasture degradation and regeneration of grass growth. Owing to changes in pastoral practices, the herders have become more prone to lose more livestock to carnivores. Using GLM models it is proven (Wald chi-square =4.551 df=11 P=O.033) that recent faulty pastoral practice change (.e.g, nuclear family, vulnerable for natural disaster and herding techniques) explains livestock losses due to the carnivores. It requires implementing livestock husbandry management in better ways. Gurvantes soum's two different villages offered ideal condition to compare carnivore conservation efficiency and way to forward to mitigate such human-wildlife conflict. Study indicated that in generally herders positive perception towards ungulates whereas carnivores Tost (conservation area) area herders' tolerance level was higher than those of baysah area (non-conservation area) (t=5.23, df=89. PItem 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.