M Sc Dissertation(WII)

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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, Gautam
Understanding 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 (p
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, p
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.

M Sc Dissertation(WII)

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