PG Thesis
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Item Systematics, biogeography and echolocation of selected Vespertilionids (Chiroptera: vespertilionidae) in Western Ghats, India(Department of Wildlife Science, College of Forestry,Vellanikkara, 2024-12-19) Mahalakshmi, C.; Sreehari, RResolving bat taxonomy is crucial to understand their remarkable diversity, evolutionary relationships, ecosystem services, managing zoonotic diseases and develop effective conservation strategies. The Western Ghats (WG) biodiversity hotspot, home to nearly 60 bat species, is considered as one of the India’s significant bat hotspots. However, this region harbors considerable cryptic species, particularly within the family Vespertilionidae (vesper bats or evening bats or vespertilionids). The present study was undertaken with the objective of elucidating the taxonomic ambiguity of selected vespertilionids in the WG by using an integrative taxonomic approach, ie, a combination of morphometric, genetic and acoustic data. For the proposed study, bats were sampled from three distinct forested landscapes of southern WG including the Idukki, Thrissur, and Wayanad districts of Kerala. Two individuals belong to the genus Tylonycteris (Bamboo bats) and one individual of Murina (Tube-nosed bat) were collected either using harp traps or mist nets. Eighteen morphological measurements, 16 cranio-dental measurements and nine acoustic parameters were measured and examined for the present study. Statistical analysis identified key distinguishing characters among the sister species of Tylonycteris and Murina. Additionally, DNA was extracted from the voucher specimens using QIAGEN DNeasy Blood and Tissue Kit. The PCR amplification was performed for the mitochondrial gene Cytochrome c oxidase subunit 1 (CO1). Phylogenetic reconstruction of the DNA sequences and calculation of the genetic divergence were conducted using the IQTREE ver. 7.490 and MEGA 7, respectively. The findings of the morphological and cranio- dental analysis revealed that the Tylonycteris genus is primarily distinguished based on prominent skull characteristics including greatest length of skull (GTL), condylo-canine length (CCL), length of upper canine to third upper molar (C-M3), and upper canine width (C1-C1). While the genus Murina have subtle morphological differences among species with forearm length (FA) as a key differentiating character. However, a detailed knowledge on the acoustic variations were lacking in order to understand the 88 overall acoustic diversity of both the genera. Phylogenetic analysis corroborated these findings, identifying significant genetic divergences between the species. The phylogenetic reconstruction confirmed that the Tylonycteris sp and Murina sp. from the WG has an affinity with the Southeast Asian (SEA) counterparts, suggesting a shared biogeographical origin. The observed genetic divergences for Tylonycteris sp. ranged from 6.6 % to 7.6% with T. fulvida and T. pachypus from SEA, while the Murina sp. exhibited a genetic distance of 3.7%, 5.5%, and 5.6% with M. walstoni sequences from South Asia (Nepal), and SEA (Vietnam and Laos), suggesting two potential new species. The present study highlights the importance of using an integrative taxonomic approach in successful species delimitation of bats. Further, this integrative approach represents a crucial step towards resolving the taxonomy of bats.Item Impact of climate change on the status and distribution of Malabar Parakeet ( Psittacula columboides), an endemic bird species of Western Ghats(College of Climate Change and Environmental Science , Vellanikkara, 2021) Keerthana, M J; Nameer, P OItem Floristic and edaphic attributes of three land use systems in Wayanad, Kerala(Department of Forest Management and Utilisation, College of Forestry, Vellanikkara, 2011) Aneesh, K S; Gopakumar, SThe present study was conducted in Thollayiram area of South Wayanad Forest Division of Wayanad district. The objective of the study is to compare the various floristic and edaphic attributes of three land use systems, viz an ecologically fragile land (EFL), a section 5 land (as per section 5 of Kerala Preservation of Trees Act (1986) and vested forest found in South Wayanad Forest Division. A total area of one hectare was surveyed in each of the three land use systems. The floristic study revealed that species richness of these land use systems were 40, 26 and 32 respectively. The major associations of trees in the ecologically fragile land were Melicope lunu-ankenda- Litsea oleoides- Litsea wightiana and Diospyros nilagirica. In section 5 land, the major associations are Litsea wightiana- Dillenia bracteata and Diospyros nilagirica whereas the vested forest is dominated with Palaquium ellipticum, Myristica beddomei, Dimocarpus longan and Mesua ferrea. Total basal area of vested forest is 44.56 m2 followed by ecologically fragile land (37.47 m2) and section 5 land (33.60 m2). By comparing the Shannon –wiener index of these land use system, vested forest recorded the highest value (2.96) followed by ecologically fragile land (2.93) and section 5 land (2.80) whereas Simpson indices are 0.93, 0.91 and 0.92 respectively. Regarding vegetation structure, a typical three storeys was noticed for ecologically fragile land and vested forest but section 5 land has only two storeys. Texture analysis revealed that soil texture of these land use systems are sandy loam. The pH values of the soil ranges from 3.84 to 4.79. The higher value of bulk density was recorded for section 5 land (1.46 g cm-3) followed by ecologically fragile land (1.34 g cm-3) and vested forest (0.88 g cm-3). There is no significant difference in the values of organic carbon and available potassium across three land use systems whereas available phosphorous was significantly higher in vested forest. The information regarding diversity of ecologically fragile land in Thollayiram will be helpful to the state forest department in designing better strategies for the long term conservation of this ecosystem.Item Species diversity and community structure of amphibians of selected agroecosystems in Thrissur, Kerala(Department of Wildlife Science, College of Forestry, Vellanikkara, 2017) Syamili, M S; Nameer, P OThe research work entitled “Species diversity and community structure of amphibians of selected agroecosystems in Thrissur, Kerala” was carried out in the agroecosystems such as Cashew Plantation, Coconut Plantation, Homegarden, Rubber Plantation, Wetlands and in Botanical Garden from January 2017 to May 2017. The main objective of the study was to find out the species diversity and community structure of amphibians of selected agroecosystems and its association with various habitat parameters. A total effort of 225 man hours were spent in the field during night. The methods adopted for the study include Quadrat Sampling, Visual Encounter Survey along with the Opportunistic Sampling. A total of 14 anurans were recorded from the study locations. Species richness was found to be highest in Rubber plantation with eight species. Encounter of amphibians was more in Wetlands followed by Rubber Plantation. All the sampling units in Homegarden and Wetlands (25 quadrats each) had the presence of amphibians. The research found significant difference in amphibian diversity among the different agroecosystems. Visual encounter survey combined with opportunistic sampling was found to be an efficient methodology to assess the amphibian species richness of an agroecosystem. The study found an inverse relation between the presence of amphibians and reptiles in the sampling units. The microhabitat variables such as soil moisture, soil pH, litter depth, maximum air temperature, and minimum air temperature has a positive influence on the presence of Pseudophilautus wynaadensis while shrub density, soil temperature at 5 cm depth and evaporation had significant inverse relation. The present work recorded two Western Ghats endemic species Indosylvirana sreeni and Pseudophilautus wynaadensis, from the agroecosystems of Thrissur while the latter was a threatened one with Endangered status as per IUCN Red List. Both the reports of Pseudophilautus wynaadensis and Indosylvirana sreeni are of interest, as they are reported from a lower altitude (50m) than the already known lowest altitude range (900m and 100m respectively) of these species. Thus, the study highlights the importance of the agroecosystems in acting as important habitats for the amphibian fauna in Kerala.