Theses and Dissertations
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Item The effect of Forestry Practices on Bird species diversity in Satpura Hill Ranges(Wildlife Institute of India, Dehradun, 1998) Mehta, Prachi; Johnsingh, A.J.T.The largest zone of dry deciduous teak forests in the country is located along the Satpura Hill ranges in Central India. Apart from being one of the oldest hill ranges in the country, Satpura Mountain houses 4 important Protected Areas (PA) in contiguity. In Madhya Pradesh, a cluster of three PAs namely Bori Wildlife Sanctuary, Pachmari Wildlife Sanctuary and Satpura National Park forms a compact unit of 1400 km2 . A large tract of 2000 km2 of reserved forests connects these three PAs to another 'one in Maharashtra, known as Melghat Tiger Reserve. The forests of Satpuras were logged under different silvicultural regimes for over a century. Timber logging in the Protected Areas was discontinued in 1991 following the Forest Conservation Act (1980), while ' it is still operational in the reserved forests. The objective of this study was to evaluate the impact of past and present silvicultural practices on bird communities in Satpura Hills. Two study sites were chosen for this purpose. During November 1992 to June 1994, the effect of different silvicultural practices on bird community was studied in Sori Wildlife Sanctuary. From 11 October 1994 to June 1996, the study was conducted in reserved forests adjacent to Melghat Tiger Reserve where selective logging was going on. The assemblage of bird community was governed by vegetation structure and floristic in Bori Wildlife Sanctuary. The decline in specialist species was primarily due to disturbance caused during felling and not 'as much due to the felling process. The availability of unlogged forests within and near the logged sites proved to be vital as they , provided the necessary refuge for ' the bird communities. The management commendation from this study suggests enumeration of all trees, shrubs and climbers in the site prior to logging that could help in obtaining a vegetation profile for the area. A complete inventory of flora and fauna of the site prior to and after logging would help in understanding the response of various species' to logging and these features could be incorporated in the felling rules. Felling of smaller trees should be avoided as it depletes the growing stockItem Avian Communities in the Riparian Areas of Bori Wildlife Sanctuary, India(Wildlife Institute of India, Dehradun, 1993) Pai, Ashwini; Johnsingh, A.J.T.Riparian areas are important as special habitats and corridors for wildlife. However, in India, riparian areas have not been studied to any detail. Also, not much is known about the avifauna of riparian habitats. The vegetation near a riparian area tends to be dense and hence distinct owing to constant availability of water. Riparian areas come under heavy use, both by livestock as well as wild animals because of the presence of water and forage. The avifauna of riparian areas is rich due to its floral complexity and structure and resources like fish and insects. This study quantified bird species diversity, avian guilds and avian community structure found in four riparian areas ( a flood plain, a riparian scrub, a disturbed nulla and an undisturbed nulla) of Bori sanctuary in Central India. The riparian areas were compared with the adjoining deciduous forest for avifaunal differences. Vegetation was studies along the riparian areas and the deciduous forests, using circular plots. Tree and shrub densities, vertical stratification of foliage and species richness were quantified. Line transects were used to estimate bird ,species richness and abundance. Bird species richness was correlated to negative variables for the two seasons. In summer the BSR was highly correlated with CC and in winters with CC. Stepwise multiple regression was used to create a habitat model for BSR in summer and in winter. Community patterns show seasonal change and also respond to structural changes of habitat.Item Shifting Cultivation and Conservation of Tropical Forest Bird Communities in Mizoram, North-East India(Wildlife Institute of India, Dehradun, 1995) Raman, T.R. Shankar; Johnsingh, A.J.T.The impact of the traditional practice of shifting cultivation or jhum on evergreen and semievergreen forest bird communities was studied in Dampa Tiger Reserve in western Mizoram, north-east India. Bird community changes through vegetation succession was studied by comparing sites that were jhum 1,5, 10,25, and 100 years ago with primary forest that has never been cleared. Systematic line transect sampling showed that bird species richness, abundance, and diversity, increased from very low levels in the I-year old fallow to maximum levels in undisturbed and 100-year old forest, with intermediate values in the 5-25 year fallows (bamboo forests). The trend of increase was not linear but hyperbolic, with a rapid increase up to 25 years approaching an asymptote at 100 years . Similarity in bird community composition between two sites was inversely related to the difference in the logarithm of their ages. Trends in bird communities were closely related to changes during vegetation succession. Vegetation variables measured were summarised by Principal Components Analysis, which yielded two components (PCI and PC2), accounting for 91.9% percent of the variance in the data-set. PCI was correlated positively with tree density, woody plant species richness, vertical stratification, depth of leaf litter, and canopy cover, and negatively with horizontal heterogeneity in the vegetation. PC 1 thus represents the changes occurring during woody plant succession. PC2 was correlated strongly with bamboo density, which shows an increase from 1 to at least 25 years after jhuming and declines in mature forest, and this axis was taken to represent bamboo succession . Bird species richness and abundance were positively correlated with PCI (woody plant succession). When the effects of PC I were removed by partial correlation, both variables were negatively correlated with PC2. The number of species in guilds such as frugivores, nectarivore insectivores, bark-feeder, canopy insectivores were positively related to PC 1. Only the bamboo-substrate feeding guild was related to PC2. These results suggest that bird community structure is largely determined by ,woody plant succession. Mature forests were found to be the main habitat for forest specialists, rare birds, and altitudinal migrants. Thirteen specialised open-country birds and two species of latitudinal migrants occurred mainly in jhumed areas. These were generally common and widespread species that will likely persist in highly disturbed areas. In terms of conservation of the forest birds of the region, mature forests are most important. The major implication of the study relates to the observed hyperbolic changes in bird species richness, and vegetation variables such as woody plant species richness. This suggests species loss in jhumed areas will be a logarithmic and not linear function of the age, i.e. a decline in jhum cycle from 100 to 50 years Ca 2-fold difference) will have less impact than a decline from 25 to 5 years Ca 5-fold difference). This implies that under the 5-10 year jhum cycles that are prevalent in most parts of north-east India today, there will be substantial losses in bird species richness. This effect may be accentuated if primary forests are not part of the jhum habitat matrix.Item Birds communities of Lower Dachigam Valley, Kashmir(Wildlife Institute of India, Dehradun, 1989) Katti, Madhusudan V.; Johnsingh, A.J.T.This study explores the ' relationship between birds and vegetation in Lower Dachigam Valley in the Kashmir Himalaya. This area falls at the transition between the Palaearctic and Indo-,Malayan biogeographic realms. It is one of the first studies of bird communities in .the Himalaya and one of few in this temperate tropical transition zone. The study 'was 'aimed at testing the following hypotheses: 1. Bird communities differ between vegetation types 2. Community characteristics are related to various habitat factors viz. vegetation height, plant species diversity and food resource diversity. Transect sampling method was employed to obtain information on bird species composition, diversity and density.