PhD Theses (WII)
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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 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 stock