M Sc Dissertation(WII)

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Author: search.filters.author.Qureshi, QamarSubject: search.filters.subject.Community structure

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    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, Qamar
    This 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, p
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    A Study on Bird Communities-Habitat Structure Relationships in Pench National Park, M.P.
    (Wildlife Institute of India, Dehradun, 1997) Jayapal, R.; Qureshi, Qamar
    There has been a number of studies on bird communities and their relationships with habitat features of floristics and physiognomy. In particular, the spatial distribution of bird communities along the axis of structural variables of a habitat has received a wider attention in the light of recent findings on landscape behaviour. Most of these works relate to either temperate or neotropical forests and our knowledge of community dynamics of tropical deciduous forests is very limited, for there has been hardly any comprehensive study in the tropics. The present study was done in the deciduous forests of the Pench National Park, Central India (M.P) between "November, 1996 and April, 1997 covering winter (November,1996-1anuary,1997) and summer (March, 1997-April, 1997). Seven distinct habitat types were identified for the study based on floristic and structural diversity. Seasonal data on 27 habitat structural variables were collected from bird-centered sampling plots. Point count census technique was employed to study the bird population. Principal Components Analysis (PCA) was used to determine the patterns of inter-relationships among the habitat structural variables. Canonical Correspondence Analysis (CCA) was done to understand the relationships of habitat components to the distribution of bird communities. For guild analysis, two different sets criteria were used to identify the guilds among the bird populations viz., food type and foraging behaviour. Twelve guilds were recognized based on the food type and, six among the insectivores with respect to foraging behaviour. The results of the PCA showed that habitat structural variables of tropical deciduous forests have a marked pattern of inter-relationships on two axes of landscape behaviour, viz., heterogeneity and complexity. But they failed to reveal any such segregation vis-a-vis bird community structure, as the scale of measurement did not address all the members of the community. The spatial distribution pattern of bird communities in relation to habitat architecture was shown by CCA to be not very tenacious; the interactions of other extraneous factors like floristics, habitat dynamics, phenophases of vegetation, disturbance, or interactions within the community may influence the habitat selection process. There was no linear correlation observed between Foliage Height Diversity and Bird Species Diversity; possible explanations and alternative views have been discussed briefly. The response of bird communities to floristics was found to be inconsistent across habitat types as positive linear relationship was detected only for Teak-dominant forests in winter, and for Anogeiss Boswellia forests and Cleistanthus collinus woodland in summer. Guild compositions of various habitat types were not found to be significanty different from each other though the seasonal change was consistent across all the habitats.