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The Role of Informal Protected Areas in Maintaining Biodiversity in the Western Ghats of India
Shonil A. Bhagwat,Cheppudira G. Kushalappa,Paul H. Williams,Nick D. Brown
Ecology and Society , 2005,
Abstract: Although it is widely believed that an important function of protected areas is to conserve species that are unable to survive elsewhere, there are very few empirical studies in which a comparison is made between biodiversity of protected areas and that of the cultivated landscape surrounding them. We examined the diversity of trees, birds, and macrofungi at 58 sites in three land-use types in a tree-covered landscape in Kodagu district in the Western Ghats of India. Ten forest reserve sites in the formal protected area, and 25 sacred groves and 23 coffee plantations in the neighboring cultivated landscape were sampled. A total of 215 tree, 86 bird, and 163 macrofungus species were recorded. The forest reserve had a large number of trees that were restricted in their distribution, and the sacred groves had a large number of macrofungi. We observed that deciduous trees and non-forest-dwelling birds increased, and evergreen trees and forest-dwelling birds decreased with increasing intensity of land management. We found that trees having non-timber uses and macrofungi useful to the local people, as well as those with medicinal properties, were abundant in sacred groves. We found no significant differences in the distribution of endemic and threatened birds across the three land-use types. Although endemic trees were more abundant in the forest reserve than in sacred groves, threatened trees were more abundant in sacred groves than in the forest reserve. We attribute the high diversity in sacred groves to the native tree cover in shade coffee plantations. We conclude that informal protected areas are as important as formal ones for biodiversity conservation in Kodagu. We recommend that a conservation strategy that recognizes informal protection traditions is essential for successful biodiversity conservation in regions where formal reserves are surrounded by a matrix of cultivated land.
Assessing Biodiversity from Space: an Example from the Western Ghats, India  [cached]
Kamaljit Bawa,Joseph Rose,K.N. Ganeshaiah,Narayani Barve
Ecology and Society , 2002,
Abstract: We demonstrate for the first time the potential use of satellite imagery to characterize areas of high and low species richness of trees in tropical forests. Our studies, conducted in the Biligiri Rangaswamy hills in the Western Ghats, India, show a high positive correlation between species richness and the Normalized Difference Vegetation Index (NDVI), which is an index of green biomass. We discuss the application of NDVI values for biodiversity assessment and monitoring, as well as for conservation planning. The NDVI is a rough measure of green biomass.
On a Dhole Trail: Examining Ecological and Anthropogenic Correlates of Dhole Habitat Occupancy in the Western Ghats of India  [PDF]
Arjun Srivathsa, Krithi K. Karanth, Devcharan Jathanna, N. Samba Kumar, K. Ullas Karanth
PLOS ONE , 2014, DOI: 10.1371/journal.pone.0098803
Abstract: Although they play a critical role in shaping ecological communities, many threatened predator species are data-deficient. The Dhole Cuon alpinus is one such rare canid with a global population thought to be <2500 wild individuals. We assessed habitat occupancy patterns of dholes in the Western Ghats of Karnataka, India, to understand ecological and anthropogenic determinants of their distribution and habitat-use. We conducted spatially replicated detection/non-detection surveys of dhole signs along forest trails at two appropriate scales: the entire landscape and a single wildlife reserve. Landscape-scale habitat occupancy was assessed across 38,728 km2 surveying 206 grid cells of 188-km2 each. Finer scale habitat-use within 935 km2 Bandipur Reserve was studied surveying 92 grid cells of 13-km2 km each. We analyzed the resulting data of dhole signs using likelihood-based habitat occupancy models. The models explicitly addressed the problematic issue of imperfect detection of dhole signs during field surveys as well as potential spatial auto-correlation between sign detections made on adjacent trail segments. We show that traditional ‘presence versus absence’ analyses underestimated dhole habitat occupancy by 60% or 8682 km2 [na?ve = 0.27; (SE) = 0.68 (0.08)] in the landscape. Addressing imperfect sign detections by estimating detection probabilities [(L) (SE) = 0.12 (0.11)] was critical for reliable estimation. Similar underestimation occurred while estimating habitat-use probability at reserve-scale [na?ve = 0.39; (SE) = 0.71 (0.06)]. At landscape scale, relative abundance of principal ungulate prey primarily influenced dhole habitat occupancy. Habitat-use within a reserve, however, was predominantly and negatively influenced by anthropogenic disturbance. Our results are the first rigorous assessment of dhole occupancy at multiple spatial scales with potential conservation value. The approach used in this study has potential utility for cost-effectively assessing spatial distribution and habitat-use in other species, landscapes and reserves.
Endemic Asian Chytrid Strain Infection in Threatened and Endemic Anurans of the Northern Western Ghats, India  [PDF]
Neelesh Dahanukar, Keerthi Krutha, Mandar S. Paingankar, Anand D. Padhye, Nikhil Modak, Sanjay Molur
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0077528
Abstract: The Western Ghats of India harbors a rich diversity of amphibians with more than 77% species endemic to this region. At least 42% of the endemic species are threatened due to several anthropogenic stressors. However, information on amphibian diseases and their impacts on amphibian populations in this region are scarce. We report the occurrence of Batrachochytridium dendrobatidis (Bd), an epidermal aquatic fungal pathogen that causes chytridiomycosis in amphibians, from the Western Ghats. In the current study we detected the occurrence of a native Asian Bd strain from three endemic and threatened species of anurans, Bombay Night Frog Nyctibatrachus humayuni, Leith's Leaping Frog Indirana leithii and Bombay Bubble Nest Frog Raorchestes bombayensis, for the first time from the northern Western Ghats of India based on diagnostic nested PCR, quantitative PCR, DNA sequencing and histopathology. While, the Bd infected I. leithii and R. bombayensis did not show any external symptoms, N. humayuni showed lesions on the skin, browning of skin and sloughing. Sequencing of Bd 5.8S ribosomal RNA gene, and the ITS1 and ITS2 regions, revealed that the current Bd strain is related to a haplotype endemic to Asia. Our findings confirm the presence of Bd in northern Western Ghats and the affected amphibians may or may not show detectable clinical symptoms. We suggest that the significance of diseases as potential threat to amphibian populations of the Western Ghats needs to be highlighted from the conservation point of view.
Molecular Identification and Ecology of a Newly Discovered Population of Sun Catfish Horabagrus brachysoma from Northern Western Ghats of India  [PDF]
Unmesh Katwate,Rupesh Raut,Mayura Khot,Mandar Paingankar,Neelesh Dahanukar
ISRN Zoology , 2012, DOI: 10.5402/2012/419320
Abstract: Horabagrus brachysoma, thought to be endemic to the southern parts of the Western Ghats of India, is recorded for the northern parts of the Western Ghats, extending the species distribution range by 180?km. We have confirmed the identity of the species and the fact that the species is indigenous to this area and not an artifact of recent introductions using molecular methods. Apart from the range extension we have also provided detailed analysis regarding the nature of morphometric variations between the sexes, length-weight relationship, and a brief discussion about the potential habitat requirements and threats to this species. By documenting the possible threats to this threatened and endemic species, we have commented on the possible measures to conserve the species in the wild. 1. Introduction Classified among the 34 global biodiversity hotspots [1], the Western Ghats of India is rich in freshwater fish diversity with more than 40% of the species being endemic to this region [2]. On one hand while new species of freshwater fish are still being described from the Western Ghats [3–6], on the other hand recent IUCN assessments have suggested that more than 58% of the endemic freshwater fish fauna of this region is threatened due to various anthropogenic stressors [7] and needs immediate conservation attention [8]. One of the major hindrance in designing and implementing potent conservation action plans for the freshwater fish in this region is the fact that they are still least understood with respect to their distribution, life history traits, population dynamics, and ecology, while many species complexes are still awaiting for proper taxonomic evaluation [7]. Limited knowledge of distribution of several fish species and continuous description of new species suggests that the freshwater fish fauna of the Western Ghats biodiversity hotspot is subject to both the Wallacean (geographical distribution of most species is poorly understood) and Linnean (most species are still not formally described) shortfalls [9]. Horabagrus Jayaram, 1955 is an endemic catfish found only in west flowing rivers of Western Ghats of India. In the order Siluriformes the exact familial affinities of Horabagrus is still debated and traditionally it has been placed under family Bagridae [10] or Schilbidae [11–13], while the recent molecular phylogeny suggests that it should belong to a new proposed family Horabagridae [14]. The genus currently comprises of two species H. brachysoma (Günther, 1864) and H. nigricollaris Pethiyagoda & Kottelat, 1994, both of which are threatened
Biodiversity of Microalgae in Western and Eastern Ghats, India
A. Suresh,R. Praveen Kumar,D. Dhanasekaran,N. Thajuddin
Pakistan Journal of Biological Sciences , 2012,
Abstract: The systematic study was conducted on the microalgal flora of Western Ghats and other parts of Eastern Ghats revealed a rich wetland algal resource for biotechnological exploration. The present study reveals with the diversity of microalgal flora in the region of Kodaikanal (10°14' N, 77°28' E), Gudalur (9°19'N 77°12'E), Agasthiyar falls (9°58'N, 78°10'E) and Kolli hills (10°12'N, 77°56'E) located in Western and Eastern Ghats of Tamilnadu, India collected in May 2011. In total, 97 species of micro algae belonging to three taxonomic groups were identified, of which 41 species belonging to Cyanophyceae, 38 species from Chlorophyceae and 18 species from Bacillariophyceae. The predominant species in Cyanophyceae were Aphanothece microscopica, Chroococcus minutus, Coelospharium dubium, Hydrococcus rivularism, Oscillatoria princeps, Nostoc muscorum, Nostoc puncteforme, Nostoc commune, Gleotricha gausii, Calothrix braunii, Rivellaria sp., Tolypothrix tenuis, Scytonema schmidtii, whereas in Chlorophyceae, Chlorella sp., Scenedesmus sp., Pediastrum duplex, Cosmarium consperum, Euastrum elagans, Micrasterias americana and in Bacillariophyceae, Navicula hallophyla, Rhophaldia gebrella, Fragellaria intermedia, Pinnularia virdis, Nitzchia palliate. Physicochemical nature of water samples were analyzed and correlated with the total microalgal diversity. Based on the correlation coefficient data, the micro algae showed positive relationship with dissolved oxygen, salinity, nutrients and negative relationship with temperature and turbidity. The species diversity index (H'), Species Richness (SR) and species evenness (J') were calculated and analyzed for microalgal population dynamic variation in the Western and Eastern Ghats.
Population, Ecology, and Threats to Two Endemic and Threatened Terrestrial Chelonians of the Western Ghats, India  [PDF]
Arun Kanagavel,Shiny M. Rehel,Rajeev Raghavan
ISRN Biodiversity , 2013, DOI: 10.1155/2013/341687
Abstract: The Western Ghats part of the Western Ghats-Sri Lanka hotspot harbors two endemic terrestrial chelonians, the Cochin forest cane turtle Vijayachelys silvatica and the Travancore tortoise Indotestudo travancorica. Population estimates as well as information on the scale and intensity of threats for these chelonians are largely unavailable. This study attempts to address these gaps for two hill ranges of the Western Ghats. Thirty random quadrats at eight forest ranges were surveyed for chelonians and their carapaces recording any found en route and also during opportunistic surveys. Three live V. silvatica and 38 I. travancorica were subsequently encountered and had overall densities of 0.006 and 0.03 individuals per hectare, respectively. These chelonians were found at quadrats with lower light intensity and soil temperature. Nine carapaces were found during the field surveys: seven the result of human consumption, one trapped in a pit, and another consumed by a wild animal. In addition to field surveys, household surveys in 26 indigenous and nonindigenous human settlements resulted in the observation of one V. silvatica and 38 I. travancorica including a carapace. Roads were surveyed to assess the threat they posed to chelonians, resulting in the observation of two I. travancorica road kills. Increased interactions and discussions between the management authorities and local communities need to be promoted if chelonian conservation is to improve in the landscape. 1. Introduction The Western Ghats (WG) region in India, part of the Western Ghats-Sri Lanka Biodiversity Hotspot is globally renowned for its diversity of endemic amphibian, reptile, and fish species [1–3]. The two endemic chelonian genera in the WG are represented by the Travancore tortoise (Indotestudo travancorica) and the Cochin forest cane turtle (Vijayachelys silvatica); both threatened with extinction [4, 5]. The cane turtle is listed as “Endangered” while the Travancore tortoise is “Vulnerable” in the IUCN Red List of Threatened Species [4, 5]. Of these sympatric, cryptic species, Travancore tortoises are known to be more widespread than cane turtles [6, 7]. The Travancore tortoise is found in rocky hills at elevations of 100–1000?m a.s.l. across the southern WG in a multitude of habitats, such as evergreen, semievergreen, bamboo, Lantana camara and Cromolarium glandulosum bushes, and rubber and teak plantations [8–12]. On the other hand, the Cochin forest cane turtle, known to be a habitat specialist associated with evergreen vegetation, has also been found in semievergreen, deciduous,
Species Diversity and Tree Regeneration Patterns in Tropical Forests of the Western Ghats, India  [PDF]
R. Jayakumar,K. K. N. Nair
ISRN Ecology , 2013, DOI: 10.1155/2013/890862
Abstract: Study Aim. To assess species diversity and tree regeneration patterns of different vegetation types of Western Ghats, India. Rarefaction was used to estimate species diversity of different vegetation types. One-way ANOVA was used to test for differences in tree density and basal area of different vegetation types. Sorenson index of similarity was used to calculate change in species composition between mature trees and regenerating individuals. Results showed that species diversity and regeneration pattern of trees differ in different vegetation types of the forest landscape. Species-area and species-individual accumulation curve (rarefaction) against equal-sized sampling area in different vegetation types showed that species heterogeneity was higher in vegetation types at mid elevations while their abundance was higher in vegetation types at higher elevations. All the vegetation types of the study area were heterogeneously distributed. Tree regeneration was higher in species rich vegetation type with no sign of human disturbances. Change in species composition across mature and regenerating phase was more frequent in disturbed forest as compared to undisturbed or less disturbed forests. New entry species occur in all the vegetation types. 1. Introduction Tropical regions of the world are frequently decked with luxuriant vegetation rich in species. The diversity of tree species is a fundamental component of total biodiversity in many ecosystems because trees are ecosystem engineers that provide resources and habitats for almost all other forest organisms [1]. In tropical forests, the diversity of tree species varies by geography, habitat parameters, and levels of disturbance [2]. Trees form the major structural and functional basis of tropical forest ecosystems and can serve as robust indicators of changes and stressors at the landscape scale [3]. The spatial heterogeneity of diversity may be the result of some underlying pattern or process such as environmental heterogeneity, biotic control, and abiotic/biotic coupling process [4]. Spatial patterns of species richness have been used extensively to identify biodiversity “hotspots” [5]. The assumption is that managing areas of high species richness equate to improved conservation outcomes. Therefore richness usually was a positive predictor of places of conservation value, if these are defined as places where species of interest are especially abundant. Understanding species diversity and distribution patterns is important for helping managers to evaluate the complexity and resources of these forests.
Morphological and Genetic Evidence for Multiple Evolutionary Distinct Lineages in the Endangered and Commercially Exploited Red Lined Torpedo Barbs Endemic to the Western Ghats of India  [PDF]
Lijo John, Siby Philip, Neelesh Dahanukar, Palakkaparambil Hamsa Anvar Ali, Josin Tharian, Rajeev Raghavan, Agostinho Antunes
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0069741
Abstract: Red lined torpedo barbs (RLTBs) (Cyprinidae: Puntius) endemic to the Western Ghats Hotspot of India, are popular and highly priced freshwater aquarium fishes. Two decades of indiscriminate exploitation for the pet trade, restricted range, fragmented populations and continuing decline in quality of habitats has resulted in their ‘Endangered’ listing. Here, we tested whether the isolated RLTB populations demonstrated considerable variation qualifying to be considered as distinct conservation targets. Multivariate morphometric analysis using 24 size-adjusted characters delineated all allopatric populations. Similarly, the species-tree highlighted a phylogeny with 12 distinct RLTB lineages corresponding to each of the different riverine populations. However, coalescence-based methods using mitochondrial DNA markers identified only eight evolutionarily distinct lineages. Divergence time analysis points to recent separation of the populations, owing to the geographical isolation, more than 5 million years ago, after the lineages were split into two ancestral stocks in the Paleocene, on north and south of a major geographical gap in the Western Ghats. Our results revealing the existence of eight evolutionarily distinct RLTB lineages calls for the re-determination of conservation targets for these cryptic and endangered taxa.
Tropical rainforest bird community structure in relation to altitude, tree species composition, and null models in the Western Ghats, India  [PDF]
T. R. Shankar Raman,N. V. Joshi,R. Sukumar
Quantitative Biology , 2005,
Abstract: Studies of species distributions on elevational gradients are essential to understand principles of community organisation as well as to conserve species in montane regions. This study examined the patterns of species richness, abundance, composition, range sizes, and distribution of rainforest birds at 14 sites along an elevational gradient (500-1400 m) in the Kalakad-Mundanthurai Tiger Reserve (KMTR) of the Western Ghats, India. In contrast to theoretical expectation, resident bird species richness did not change significantly with elevation although the species composition changed substantially (<10% similarity) between the lowest and highest elevation sites. Constancy in species richness was possibly due to relative constancy in productivity and lack of elevational trends in vegetation structure. Elevational range size of birds, expected to increase with elevation according to Rapoport's rule, was found to show a contrasting inverse U-shaped pattern because species with narrow elevational distributions, including endemics, occurred at both ends of the gradient (below 800 m and above 1,200 m). Bird species composition also did not vary randomly along the gradient as assessed using a hierarchy of null models of community assembly, from completely unconstrained models to ones with species richness and range-size distribution restrictions. Instead, bird community composition was significantly correlated with elevation and tree species composition of sites, indicating the influence of deterministic factors on bird community structure. Conservation of low- and high-elevation areas and maintenance of tree species composition against habitat alteration are important for bird conservation in the southern Western Ghats rainforests.
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