M Sc Dissertation(WII)
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Item Impacts of Road Related Disturbances on Mammalian and Vegetational Assemblages : A Case Study of SH-33 Passing Through Nagarahole Tiger Reserve, Karnataka(Wildlife Institute of India, Dehradun, 2019) Siva, R.; Habib, Bilal; Gubbi, SanjayUpcoming economies such as India need to strengthen their road network for the socioeconomic development of the country. While roads are important to the country, they are a threat to wildlife when they pass through the protected areas and other ecologically sensitive areas. Multiple impacts of roads on wildlife range from habitat loss, edge effects, vehicular traffic, pollution, animal mortality, barrier effect to invasion by alien flora and fauna. This project revealed the impacts of road-related disturbances on mammals and vegetation in Nagarahole Tiger Reserve, Karnataka. Mysore-Mananthavadi road (SH-33) is passing through the southern part of Nagarahole Tiger Reserve that has two segments in which one segment is decommissioned and another segment is closed for the vehicular traffic during the night. Here, I have compared the habitat use of mammals in these two segments using camera traps and assessed the impact of road-related disturbances on vegetation in this road by vegetation sampling. Vehicular density was estimated using the camera traps in these two segments.The study results revealed the avoidance of vehicular traffic segment by the mammals and activity pattern seems to be relatively unaffected by the vehicular traffic. It also shows the change in the vegetation composition and spread of invasive species due to road related disturbances.Item Assessing Population Status Roost Site Selection and Fruit Damage by the India Fly fox Pteropus giganteurs in Southern Karnataka: The Flying Foreesters(Wildlife Institute of India, Dehradun, 2015) Raj, Versha M.; Qureshi, QamarFlying foxes Pteropus giganteus, playa key role in pollination and forest regeneration as seed dispersers. Despite this beneficial role, they are persecuted for being an agricultural pest in commercial orchards. More recently in India, they have been known to be reservoirs of deadly zoonotic diseases like Nipah. Over the past two decades rapid urbanization, leading to habitat and roost tree destruction has resulted in decline in population of the Indian flying fox. As a result, incidence of flying foxes visiting commercial orchards has increased which in tum has led to conflict between large-scale commercial fruit growers and flying foxes. Assessing the present population status, and identifying the habitat preferences could help in understanding the risk of fruit damage in the surrounding areas, and will help in conservation of the keystone species and there by prevent their persecution also. A total of 51 roosts were identified which were used to assess the population status and change over time. Four methods of population estimation were compared to select the most reliable. method. Photographic count method was found to be most reliable for of population estimation. At the landscape level, proximity to water bodies and intensity of urbanization influenced the occurrence of roosts. 11.38 % of the total study are was found to be suitable for roosting (potential habitat). Amongst the individual tree characters, tree GBH and tree height were found to strongly influence the roost selection. In commercial orchards, Pteropus giganteus was found to be responsible for significant amount of damage in orchards cultivating Guava, Mango and Sapota. Based on the extent of damage they were ranked second most important animal pest in these commercial orchards after birds. Further work on estimating actual fruit damages would be required to confirm the role of the Indian flying fox as pest responsible for causing severe fruit damages in commercial orchards, for which they have been constantly persecuted.Item Factors Influencing Movement Pattern Habitat Use and Distribution of King Cobra (Ophiophagus hannah)- A Multiscale Approach(Wildlife Institute of India, Dehradun, 2011) Rao, Chetan S.; Talukdar, G.; Choudhury, B.C.The king cobra (Ophiophagus hannah) is the largest species of venomous snake in the world. It is a widely distributed species occurring in India and Southeast Asia. Most of the habitat use studies of ophidians are responses of ambient temperature. These results are often correlated with temperate areas where there is a significant shift in temperature annually. In tropical ecosystems, to understand ecology of a large bodied species like the king cobra would be interesting, knowing the fact that very little work has been done so far. The objective of my study was to procure relationship of ecographic variables on movement pattern, habitat use and distribution of king cobras at an individual and at a population level. This study was carried out in Agumbe, Karnataka in the Western Ghats region of India for 4 months during December 20 I 0 to April 2011 . Habitat utilization points were sampled throughout the study area, which basically was placed within the boundaries of a 2x2 sq.km grid enclosing all the presence locations collected during five years from the ongoing King Cobra Telemetry Project conducted by the Agumbe Rainforest Research Station and the University of Arizona in collaboration with the Karnataka state forest department. Retreat sites (n=262) were selected where the tagged (n=5) had been recorded and sampled for microhabitat variables. Nest sites (n=13) were also looked into, to explore site selection by females. A total of 30 ad libitum sightings of king cobras were recorded during the study. Prey density walk was carried out to derive a relative abundance based on encounter rate in the study area that came to be 1.24 animals/km. A total of 9 species of prey were encountered during prey density walks. The kernel estimates and minimum convex polygon for four radio tagged individuals was calculated for home ranges and area vs. availability was computed for habitat preference and use using Jacob's (1974) Index. The results of this study show a strong correlation of ambient temperature of range 20- 35°C (Beta coefficients 7.7eI0-l ± 0.0545) and relative humidity (70-90%) (Beta 15 coefficients 1.25 ± 1.14) with movement pattern and habitat site selection and also affect distribution patterns of this particular king cobra sub population. It is also found that king cobras do not particularly obligate themselves to a particular habitat type except for some degree of preference towards evergreen forest. The microhabitat however, influencing king cobra movement and habitat use are fallen logs on the forest floor (Beta coefficients 2.327e+00 ± 5.113e-Ol) and dead vegetation on the forest floor (Beta coefficients 2.042e-02 ± 6.796e-03) which have a stronger correlation with presence while ground burrows show a negative correlation. Leaf Litter Depth in the forest floor in sites with range of 4-7 inches deep (Beta coefficients 0.64269 ± 0.30998) influences nest site selection. Using secondary rescue data of five years and all the other presence records for king cobras in the wild, I ran a MaxEnt presence only model (auto model) using only environmental variables taken from BIOCLIM to test environmental parameters influencing distribution. The places of higher precipitation within the study area indicate a higher influence on occurrence and places of higher temperature and aridity regimes does not indicate occurrence of king cobras. The management recommendations for conserving such large bodied snakes would be a multidimensional approach. The local people within the study area do not kill king cobras, due to religious reasons. However, these attitudes are changing and so also some of the tolerant ideologies of the local people. King cobras have been found to occur more in a landscape matrix dominated by evergreen forests and decline in evergreen forest due to land use conversion could be the emerging possible threats to king cobra in the Western Ghats.Item Behavioural Ecology of Colony Formation and Function of Colonial Breeding in Chtnut-Headed Bee-Eater.(Wildlife Institute of India, Dehradun, 2011) Supriya; Vasudevan, K.; Mohan, D.Breeding in densely distributed territories that contain no other resources apart from breeding site is known as colonial breeding. Despite several long-term investigations, there are several questions regarding colony formation, the function of coloniality and the variation in colony sizes that remain unanswered. Chestnut-headed bee-eaters (Merops leschenaulti) are tropical Old World birds (Family Meropidae) that breed both solitarily and in small colonies. Hence they are well-suited subjects for the study of colonial breeding. This study was conducted for five months from December 2010 to May 2011 in parts of Haliyal division and Karwar division in Uttara Kannada district, Karnataka. It is an attempt to explain the variation in colony size through gaining insights into the behaviour of colony formation and function of colonial breeding. A combination of measuring habitat characteristics, capturing and measuring birds, recording reproductive success of breeding pairs across a gradient of colony sizes and behavioural observations were used. A total of 17 nests were found during the course of the study distributed over three colonies and five solitary nests. No significant difference was found between habitat characteristics at solitary and colony nests. Also, there was no shortage of potential breeding sites, as found by the ratio of number of nests to the amount of substrate available. This suggests that the mechanism of colony formation in CHB is conspecific attraction and is not merely habitat mediated aggregation. The body size of the colony nesters was found to be greater than the body size of solitary nesters. This implies that the optimum colony-size is different for different individuals, with larger individuals having a preference for colony nesting. Program MARK was used to analyze nest survival data. It was found that the daily survival rate of nests was not significantly different across colonies of different sizes, lending further credence to the hypothesis that different individuals have different colony-size optima. Colony nests were initiated about a week before the solitary nests and nesting was more synchronous at colony sites. During the nest digging stage of breeding, a number of aerial chases were observed between the birds, which hint at a role for despotism in influencing variation in colony sizes. Provisioning frequency was found to be higher and showing larger variation at solitary nests than at colony nests. A possible explanation for this is that there is greater competition at colony sites. Therefore, colony-nesting must be having some other benefit that compensates for the cost of competition. Further investigations into the conspecific cue that mediates colony formation and· the benefit of coloniality need to be carried out.Item Responses Shown by Bird Communities to Teak Palatations in Sagar Forest Division, Karnataka(Wildlife Institute of India, Dehradun, 2009) Barve, Sahas S.; Mohan, D.; Qureshi, QamarThis study was aimed at discerning the responses shown by bird communities to teak plantations of various age classes in Sagar Forest Division, Karnataka within Latitude 13° 36' and 14° 38' North 74° Longitude 38' and 75° 32'East Latitude. Birds were sampled using line transects in three habitat strata, natural plantations, mature teak plantations and young teak plantations. Density, diversity and community similarity were the chief ecological responses that were quantified to bring out differences in the usage of forest plantations by native bird fauna. Habitat (vegetation) correlates, both structural and floristic were quantified to establish the reasons for differences. The sampling period was from December 2008 to April 2009. This period was divided into two seasons, winter and summer. A total of 9 transects were laid, marked and sampled at least 4 times per season. Birds were divided into three feeding guilds and three habitat guilds for analysis. The overall density of birds across the three strata was found to be higher in summer than in winter. However a guild level analysis showed that in winter while insectivorous birds were most abundant in natural forest with decreasing density towards young plantations (F (6.241) , p< 0.05). There was no difference in their density in summer. Phytophagous birds showed the exact reverse trend. Density of this guild was higher in young plantations than natural forests and mature plantations in winter and summer (F(S.689), p< 0.05), (F (14.302), p< 0.01) respectively. Overall diversity of birds showed a trend of decreasing species richness from natural forests to young plantations in both seasons. However this difference was almost non existent in summer at the guild level. The abundance of birds belonging to evergreen and moist deciduous forests shows a consistent· rise in abundance from winter to summer in all the three strata. There is also evidence that there is ingression of individuals of species that were common to both seasons possibly for nesting. The overall community similarity is quite high between the three strata and it increases from winter to summer. Bird diversity was found to be affected by the vertical spread of vegetation and tree height heterogeneity (R=0.871, pItem Patterns in plant species richness and diversity in the forest fragments of Western Ghats, Karnataka.(Wildlife Institute of India, Dehradun, 2007) Page, Navendu V.; Qureshi, Qamar; Rawat, G.S.Patterns of species richness diversity and distribution, and the factors affecting these patterns have always attracted the attention of many ecologists. Degree of fragmentation is one such factor affecting the species richness and composition also of great importance to conservation biology in light of rapid loss of biodiversity. The study examined the patterns of distribution and species richness and its correlates in a fragmented landscape in Kodagu district, Western Ghats, Karnataka. The study also examined some of the factors affecting distribution of epiphytes such as distribution along the tree height gradient and host specificity. A total of 129 species of trees, 29 species of Iians as and 68 species of vascular epiphytes were recorded in 56, 25m x 25m square plots. 60 species of shrubs were recorded in 90, 5m x 5m square plots. Patch area was found to be significantly correlated with tree species richness, but area was not correlated with shrub, liana and epiphyte species richness. However plant density used as measure of site specific productivity along with area were significantly correlated with lianas and epiphyte richness. Neither of these could explain the variation in shrub species richness. Lianas and shrubs did not show any such trend but epiphyte richness showed a negative trend in rarefied species richness with increase in area. Rank abundance curves indicated that Reserve forest had the most equitable distribution of abundance classes and also more number of rare species. Species composition was found to differ significantly across different size classes. All the plant communities showed moderate levels of nestedness. Distribution of an epiphyte along the tree was not influenced by the mode of dispersal alone. There was no strong evidence in support of host specificity however some selective host species were found to be favoured by epiphytes.Item The Impact of Land Use Change on Litter Beetle and Ant Communities a Coffee-Dominated Landscape in Chickmagalur District, Karnataka(Wildlife Institute of India, Dehradun, 2001) Badrinarayan, Smitha; Krishnamurthy, Jagdish; Uniyal, V.P.Human-modified habitats dominate the landscape on earth. There is an urgent need for investigations into the diversity of biota supported by different land use systems that replace forests. The plantation of coffee is one such land use that occurs in large tracts of the Western Ghats in Karnataka. An observational study on changes in litter faunal communities caused by conversion 'of forests to coffee was attempted at the Koppa and Narasimharajapura taluks of Chickmagalur district. Four replicate blocks containing three treatments: forest, polyculture shade coffee plantations and mono culture shade coffee plantations, were selected using detailed spatial information that existed for this area. These included a land cover map, aerial photographs and topographic sheets. The information from these sources was used to obtain a list of possible study sites, the suitability of which were assessed on the basis of field visits and interviews of the locals. Litter beetle and ant communities were sampled using pitfall traps along two transects within each of the treatments. Measurements of microclimate, vegetation structure and litter parameters were made along with sampling for litter fauna. The organisms obtained in the pitfall :traps were sorted out and the ants and beetles occurring in it were identified to the level of morphospecies. Comparisons of the diversity of beetle and ant morpho species in the forest and two coffee shade treatments were made on the basis of the occurrence and abundance of different morphospecies. Cluster analyses of the twelve sites were done based on the distances between the communities found in them. Patterns revealed using exploratory data analyses were tested using quantitative statistical sampling. There were significant differences in microhabitat structure between the three treatments. Forests were found to be more humid and had more equitable conditions than either of the coffee systems. The beetle and ant communities in the three treatments were also found to be distinctly different. Beetle morphospecies richness and abundance was highest in forests and lowest in the coffee monoculture shade systems. Ants, while having an equal number of morphospecies across the three treatments, were seen to be dominated in abundance by a few species in the coffee mono culture shade systems. Generally, forest sites were seen to cluster together in one group while coffee mono culture shade sites clustered in another. The polyculture shade coffee treatments were seen to be intermediate in their community composition between forests and mono culture shade coffee plantations. The high community turnover rates across the landscape suggest that even remnant forest patches in this coffee dominated landscape need to be protected from further degradation. For further conservation of the litter faunal community, traditional coffee polyculture shade systems need to be promoted to halt conversion to silver oak dominated agricultural systems.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.