Theses and Dissertations
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Item Habitat selection of birds in New Forest, Dehra Dun, India.(Wildlife Institute of India, Dehradun, 2007) Mohan, Dhananjai; Johnsingh, A.J.T.The New Forest campus is primarily a man-made ecosystem created in the 1920s mainly to house the Forest Research Institute. Much of the area of what is New Forest today was under agricultural fields till they were acquired in 1920s by the British and there after considerably large areas of this sprawling campus were developed into demonstration forests, gardens, experimental plantations areas, and arboretum by planting them up. In addition, there is a block of natural forest on the northern part of the campus which belongs to 3C2b(i) type (Moist Bhabhar Sal forests). The present study was restricted to ca. 150 ha of wooded part of the 463 ha of the campus. Two hundred and seventy six birds have been reported from the campus till date. The campus is managed through management plans prepared at a ten year cycle. Four distinct vegetation types were identified in the wooded parts of the New Forest campus based on the vegetation composition and structure. These, namely, Chir Pine plantations, Gardens, Mixed plantations and Natural forests were recognized as the four distinct habitats for the birds, the first three being man-made. The bird abundance was estimated by conducting point transects which were done over a two year period from October 2004 to June 2006 and collected habitat structure and composition data by laying out vegetation plots around the point locations for the bird transects (bird centered vegetation sampling). The guild structure of the birds of New Forest was investigated and factors determining it were identified. The seasonal change in guild structures both within and across various habitat types was also looked into. Birds were divided into fifteen fine feeding guilds. A distinct habitat selection by birds was observed amongst the four identified habitats of New Forest as seen from multiple response permutation procedure (MRPP) and hierarchical clustering of sample points in different habitats on the basis of bird composition. The present study shows that despite some degree of biotic pressures, natural forest habitat still possesses the highest bird richness as compared to the well-preserved mature plantations even with mixed crop. It also supports the highest density of birds of all the habitats of New Forest. The highest number of indicator birds has also been reported from this habitat. A large number of biome restricted bird are reported from this habitat which has led to the declaration of New Forest as an Important Bird Area. This habitat which is typical of northern part of Dehradun valley is under great threat in most parts owing to a rapid spread of urbanization and the patch in New Forest may be the only one to provide long term preservation to its typical flora and birds.Item Conservation status of fishes in the tributaries of Ramganga with special reference to golden mahseer Tor putitora Hamillton(Wildlife Institute of India, Dehradun, 2005) Atkore, Vidyadhar Mahadeorao; Sivakumar, K.; Johnsingh, A.J.T.A common goal in the studies of community ecology is to uncover patterns of species abundance or distribution and determining the factors that are responsible for them. Himalayan waters are unique in the ichthyofaunal diversity. To know what species are here, fish sampling was carried out with help of cast net. Three rivers were identified for the stratified fish sampling. Each river was divided at two hundred meter distance apart. Each segment was sampled thrice though out study period. Morphometric measurements were taken in the field. Habitat parameters were also recorded as on same day of fish sampling. Result shows that MandaI River had .more species richness followed by Khoh and Kolhu. Forty three species belonging to five orders and ten families (four species yet to identify) were recorded in the study river. Of these, approximately 80 % were classified into the rare category. Tor putitora, Garra gotyla Barilius barila, and Scizothorax richardson are listed in the IUCN Red list. However, endangered golden mahseer was one of the commonest fish. The reason could be the preferred spawning habitat ground or abundant food availability. Population estimation was estimated by using Jolly Seber method, resulted high standard error. Low number of recapture sessions could be the reason. Mostly juveniles of 6-10 cm size classes were abundant in all three rivers followed by 11-15 cm group. The total length measured for Golden mahseer varies from 3 cm to 28 cm. The condition factor was calculated based on the available size class. Result showed that 20-25 cm size classes of golden mahseer were in better condition in the Study Rivers. However, condition for size class 0-5 cm fish was better in Kolhu River than others. The 6-10 cm size class, 15-20 cm and 21-25 cm were doing better in the MandaI than two rivers.Item Density, Biomass and Habitat Occupancy of Ungulates in Bhadra Tiger Reserve, Karnataka(Wildlife Institute of India, Dehradun, 2001) Jathanna, Devcharan; Johnsingh, A.J.T.The distribution and abundance of ungulates prey of tiger were studied in the tropical moist deciduous forest of Bhadra Tiger Reserve, Karnataka from November 2000 to April 2001. The species of interest were chital, sambar, Muntjac and gaur. The line transect method was used to estimate absolute densities of the study species in November 2000. Distribution of the study species was studied using dung as an indicator of occupancy. Logistic regression models was used to examine species presence/absence and habitat parameters.Item Distribution and movement patterns of the Himalayan Black Bear (Selenarctos thibetanus Cuvier) in Dachigam National Park, Kashmir(Wildlife Institute of India, Dehradun, 1989) Saberwal, Vasant; Johnsingh, A.J.T.This study investigates the distribution patterns of the Himalayan Black Bear (Selenarctos thibetanus) in Dachigam Rational Park, Kashmir. It involved basically two components. (i) looking at the differential usage of different parts of the park by bears over a five month study period. and (ii) the spatio-temporal variation in the distribution and availability of fruit during the study. Dachigam National Park of 141 sq. km ranges in altitude from l800m to 4400m. It is divided into Lower (2& sq km) and Upper (115 sq km) Dachigam. Lower Dachigam (LO) is characterized by a broad valley flanked by steep hillsides. Upper Dchigam (UO) is composed of several gullies separated by fairly steep ridges. The valley vegetation is broad leaved, moist deciduous forest with an unusually high abundance pf fruit species. The slopes on either side are dominated by grass (south facing slopes) or a combination of grass, conifers and shrubs (north facing slopes). The vegetation of Upper Dachigam is mainly composed of coniferous species, with alpine meadows in the higher areas. Transects were walked through Lower Dachigam, considered to have over 90% of the Black Bear population of the park. to record animal locations and signs. especially droppings. 100m segments were marked along these transects and sightings and signs plotted accordingly. These segments were the basis of the habitat mapping exercise. A subjective estimate of the abundance of key fruit species was made for each segment. A phenology study looked at the timing of fruiting of key species. Data analysis shows a good, though not significant correlation between sighting frequencies and fruit availability. However there is strong suggestive evidence to indicate that anilla1 movements are largely Controlled by the spatial distribution and phenological status of five to six key fruit species. The lack of significance is probably due to the small data set. The study indicated the lack of defended territories. Instead, as reported from studies on the American Black Bear (Ursus americanus), there are marked seasonal shifts in the use of the home range. Feeding aggregations of up to 20 bears in one hectare are common. Densities of over 1.5 bears per sq km were recorded in Lower Dachigam at times of high fruit abundance. For two months of the year, May and August, black bears disperse out of the park due to very low food availability. Crop raiding (apple, cherry, and maize) is common at this time. The unusually high abundance levels of fruit in Lower Dachigam (due to oak, walnut, and mulberry plantations, over 70 years old) supports a high density of bears at certain times of the year. However, the lack of sufficient fruit at other times of the year is resulting in increasing levels of conflict with the local human population. Problems of oak and walnut regeneration, and the implications of extremely localized oak distribution are discussed. A more detailed study investigating the problem is suggested.