M Sc Dissertation(WII)
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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 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.