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 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 Habitat Selection by Indian Peafowl (Pavo cristatus linn) in Gir forest, India(Wildlife Institute of India, Dehradun, 1993) Trivedi, Pranav; Johnsingh, A.J.T.A study on habitat selection by Indian peafowl (Pavo cristatus) was carried out in Gir National Park and Sanctuary over a period of five months. Open width line transects were laid at three study sites in West, Central and East Gir respectively to obtained information on availabili ty and use of habitats. Three hundred and thirty sightings were obtained in 90 transect walks (totalling to ca 113 km), of which two hundred and fifty occurred in West, and forty each in Central and East Gir. As sampling intensity was the highest in Sasan (West Gir), much of the analyses is based on the data collected here. Peafowl distribution was found to be clumped, with the degree and site of clumping being affected by water and food availabilityItem 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 The Grey tit (Parus major caschmerensis) in Northern India: Behaviour and Ecology in the non-breeding season(Wildlife Institute of India, Dehradun, 1995) Quader, Suhel; Johnsingh, A.J.T.; Qureshi, QamarStudied the grey tit (Parus major caschmerensis) in Naina Devi Sanctuary. in the Shivalik hills of the Himachal Pradesh Himalaya. This is a subspecies of the well-studied great tit which ranges over a large part of Eurasia. The study had two main components: a. to investigate the non-breeding behaviour and ecology of this bird in India, and to interpret the findings with respect to what is known about the species from more northern areas (a comparative approach). b. to study the behaviour of individuals in the context of short· and long-tenn processes (in the winter, examples of these might be survival and reproduction. respectively), I collected data on colour-banded grey tits by following individuals, and recording behaviour using the point-sampling technique with one-minute intervals. Field work was carried out between December 1994 and April 1995. Throughout this study, I refer to the subspecies in India as grey tits, those studied in Europe and Japan as the great tit, and to the species as a whole as Parus major. In a comparison with what is known about great tits, the following points emerge: .Grey tits do not spend the winter in flocks of conspecifics; instead. they are either solitary or in pairs. This is associated with comparatively high winter temperatures, and may be the result of a low seasonality in resource abundance allowing for greater territorial site-fidelity. Sexual dimorphism in bill shape mirrors that found in a previous study on great tits in England, where males have deeper and shorter beaks than females, tend to forage more on beech seeds, and are more efficient at doing so than females. Grey tits show a sexual dimorphism in beak shape paralleling this, and males exhibit a strong tendency to forage more on Acacia catechu (from which largely pods are taken) than females, implying that similar ecomorphological processes can operate in populations widely separated in space. Grey tits use a wider variety of foraging substrates than their more northern counterparts, and correspondingly spend less time foraging on the ground. This is' associated with the absence of any congeners, although whether it is a case of competitive release is open to dispute. The Indian birds seem to spend more time feeding than what has been reported for English great tits. The greater time spent feeding is perhaps unexpected given the comparatively higher winter temperatures, and longer day-lengths in Naina Devi than in northern Europe. While a strict comparison of different studies may not be entirely valid, the solitary/pair living habit of grey tits may result in lower levels of aggression, and this may allow for more feeding time. The date of laying is related to the duration for which the male and female have been together (i.e pairing date). Birds which paired early bred early, though this is based on a limited sample of four pairs. If this relationship is causal, and if reproductive success decreases through the breeding season (as has been shown for many temperate species), it would imply a strong selection pressure for early pairing in the great tit. As breeding approached, males spent less time feeding than in the winter, and were involved in greater territorial activity such as singing. Female time budgets showed a similar, though nonsignificant trend over the season. Pooling sexes, the proportion of time spent tended towards a decrease as summer drew near. This decrease approached statistical significance.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 A Study of Heterospecific Flocking and Nonbreeding Bird Community Structure of Rajaji National Park(Wildlife Institute of India, Dehradun, 1991) Rai, Nitin D.; Johnsingh, A.J.T.Many workers have found a direct relationship between bird community structure and vegetation structure. To investigate this and describe the heterospecific flocking behaviour of nonbreeding birds I sampled five habitat types in the Dholkhand range of Rajaji National Park, U.P., India. Inter-habitat differences in flocking and bird community structure were considered. I used the line transect technique to sample bird communities. Mixed species flocks were observed to investigate why birds flock. The guild structure based on diet and foraging strategy showed a marked difference between habitats. Species richness was estimated using rarefaction analysis, a procedure that standardizes the unequal area of the different sites. I used a correlational approach to answer the question – what determines bird species richness ? Foliage height diversity, canopy cover, canopy height, canopy height difference, tree density, tree species numbers and cross sectional area, were used as the vegetation variables. Results indicate that none of the variables have strong predictive value though tree species number which is the only floristic measure of the habitats has a consistent influence independent of sample size. The guild structures suggest that the bird communities vary with floristic aspects, of the habitats. To test my hypothesis that flocking is a response to food availability I related bird densities, which is an indicator of food availability, to flocking tendencies and found a inverse relationship. I also found behavioural evidence to suggest that flocking is also an anti-predatory strategy.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.