Theses and Dissertations
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Item Distribution of breeding Phylloscopus and Seicercus warblers in the Himalayas: Role of ecomorphology and competition.(Wildlife Institute of India, Dehradun, 2012) Ghosh, Mousumi; Rawat, G.S.; Price, TrevorPresent study is carried out for the overarching goal of understanding the ecological and historical determinants of geographic and altitudinal distribution of sixteen breeding Phylloscopus and Seicercus species in the Himalayas. The broad research objectives were as follows: 1. Assess the availability of arthropod resources across the eastern and western Himalaya along the elevational gradients. 2. Identify the climatic correlates of the breeding distribution of Phylloscopidae. 3. Examine the geographic variation in foraging ecology of Phylloscopidae across the Himalayan bioclimatic gradient.Item An ecological study on the pheasants of Great Himalayan National Park, Western Himalaya.(Wildlife Institute of India, Dehradun, 2003) Ramesh, K.; Rawat, G.S.The primary focus of the study was to describe the ecological and spatial distribution of three sympatric pheasant species, namely, Himalayan monal (Lophophorus impejanus), koklass (Pucrasia macrolopha) and western tragopan (Tragopan melanocephalus) in the Great Himalayan National Park (GHNP; 31 0 33' - 31 0 57' N and 770 17' - 770 52' E) in Himachal Pradesh, India. The specific were to: (i) review and test the currently available count techniques and provide estimates of relative abundance; (ii) document group size characteristics; (iii) describe habitat preference and investigate species coexistence; and (iv) develop a spatial model to predict availability of the potential habitats and the probability of occurrence of the study species. The study design included three broad approaches, namely, 1) field sampling, to estimate relative abundance and other behavioral and ecological parameters, 2) associative approach, to establish a relationship between the ecological distribution of the study species and habitat characteristics, and 3) Geographical Information System (GIS) based predictive spatial modelling. An area of 16 km2 was selected within GHNP, based on reconnaissance survey and literature, to serve as an intensive study areaItem An ecological study of sympatric hornbills and fruiting patterns in a tropical forest of Arunachal Pradesh.(Wildlife Institute of India, Dehradun, 2001) Datta, Aparajita; Rawat, G.S.The tropical forests in north-east India have a diverse assemblage of hornbills (Bucerotidae), ranging from the cooperatively breeding Brown hornbills (Anorrhinus spp.) to the monogamous and territorial Great hornbill (Buceros b{cornis). Focussing on three sympatric species, the Great hom bill (Buceros bicornis), the Wreathed hornbill (Aceros undulatus), and the Oriental Pied hornbill (Anthracoceros albirostris), in a lowland semievergreen forest of Arunachal Pradesh this study attempted. the dispersal syndromes of tree species were evaluated, and their patterns of flowering and fruiting examined. The study was conducted in the lowland semievergreen forests of Pakhui National Park, western Arunachal Pradesh.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 Winter Habitat Use by Monal Pheasant (Lophophorus impejanus)in Kedarnath Wildlife Sanctuary, Western Himalaya(Wildlife Institute of India, Dehradun, 1997) Kumar, R. Suresh; Rawat, G.S.; Sathyakumar, S.I studied the winter habitat use by Monal "pheasant (Lophophorus impejanus), in Kedanath Wildlife Sanctuary, Western Himalaya, from November 1996 to April 1997. The study period included three seasons: autumn (November-December), winter (January-February-March), and spring (April). The objectives of the study were to quantify availability and utilization of the different habitats, which were named after prominent vegetation types in the three seasons, identify habitat variables influencing monal habitat use, and determine the sex ratio, group size and group composition of mona!. Existing trails and transects (eight in number) were used to quantify the above mentioned parameters. Eight different vegetation types were identified in the study area. They are : Oak-Rhododendron Forest (ORF), Oak-Rhododendron Degraded forest (ORD), Oak-Rhododendron-Lyonia (ORL), Maple-Oak- Rhododendron forest (MOR), Fir forest (FIR), Scattered Tree and Scrub (STS), Alpine Scrub (AS), Alpine Meadows and Rocks (AMR), and a separate category 'cliffs'. During the entire study period monal Showed preference for ORF. Within this vegetation type, they were seen mostly close to the streams. Most of the monal sightings (66.7%) during autumn were between 2900 m and 3200 m altitudes. Monal showed movement to slightly lower altitudes (to 2800 m) during peak winter. During late March, the snow had started to melt and a gradual movement of monal to higher altitudes was noticed. Monal showed strong preference for dense ORF with high litter cover during autumn and winter. At the onset of spring, there was a shift in the habitat use and they showed preference for cliffs. The males used such areas for displaying to the females. Other habitat variables such as bamboo cover, canopy cover, and presence of snow played an important role in the choice of habitat by monal. The mean group size did not vary significantly across the seasons. During autumn, male and female monal were in loose groups i.e., females had tendency to form small groups, whereas males remained more or less solitary. After the fust snow, distinct group formations were seen. The groups were categorised into an all-male group of seven or eight individuals, all-female groups of 10 to 12 individuals, mixed groups, and solitary males. The females remained in groups throughout the study period, while the males remained in groups only for a short span and only during peak winter. Monal started to move to the higher reaches during late March, and from then on, solitary males were quite often encountered.