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Item Conservation status of tiger and associated species in the Terai Arc Landscape, India(Wildlife Institute of India, Dehradun, 2004) Johnsingh, A.J.T.; Ramesh, K.; Qureshi, Q.; David, A.; Goyal, S.P.; Rawat, G.S.; Rajapandian, K.; Prasad, S.The Indian portion of Terai Arc Landscape (TAL), stretching from Yamuna river in the west to Valmiki Tiger Reserve, Bihar in the east, spreads across five states along the Shivaliks and Gangetic plains. This unique Landscape consists of two distinct zones: (i) bhabar, characterized by a hilly terrain with course alluvium and boulders, and sal mixed & miscellaneous vegetation communities and (ii) terai, characterized by fine alluvium and clay rich swamps dominated by a mosaic of tall grasslands and sal forests. The terai, in particular, is listed among the globally important 200 ecoregions for its unique large mammal assemblage. Over the decades as a result of conquest of malaria, establishment of numerous settlements and consequent increase in human population, this Landscape has become highly fragmented and degraded. This has led to the local extinction of species such as one-horned rhinoceros (Rhinoceros unicornis), swamp deer (Cervus duvauceli) and hog deer (Axis porcinus), for example, west of Sharda river. Despite its ecological richness and faster rate of degradation and species extinction, conservation initiatives are far from desired in this Landscape, perhaps due to inadequate information and lack of coordinated efforts. Given this circumstance, the Wildlife Institute of India (WII) submitted a proposal to Save the Tiger Fund (National Fish and Wildlife Foundation, USA) to carry out a survey of TAL on the Indian side, which is ca. 42,700km2 with a forest area of ca. 15,000 km2. Save the Tiger Fund allotted US $53,500 and an 18-month project was initiated in July 2002. The project objectives were to (i) develop spatial data base on the TAL, (ii) assess tiger (Panthera tigris) and large ungulate distribution and status, (iii) describe the status of the Landscape and its vegetation characteristics and (iv) document the socioeconomic conditions of the local people and major disturbance factors. Indian Remote Sensing (1C/1D) satellite images with the spatial resolution of 188m (WiFS) and 23.5m (LISS III) pixel sizes, and Survey of India topographic maps were used for habitat mapping and other spatial database. The study team surveyed the entire Landscape twice between October 2002 and June 2003 for assessing the status of tiger and other associated large mammal species, and habitat conditions. Extensive sampling of 246 foot transects covering 1001.2km and 1530 circular plots, with nested design, were carried out across the TAL. Demographic and socioeconomic profiles of people were derived primarily from the raw data of 1991 Census. Owing to the applied nature of the project, it was decided to hold a two-day workshop to share the findings and to attain synergy among Forest Officials, NGOs and other conservation agencies for implementation in the field. The study revealed that the TAL contains homogenous vegetation communities of eight broad types, but the structural components vary highly across the Landscape. The tiger habitats on the Indian side are in nine blocks (referred as Tiger Habitat Blocks, THB) and the largest block (ca. 4,000 km2) is around Corbett TR. The forests in Kalsi, Dehradun and Haridwar Forest Divisions in Uttaranchal and Bijnor Plantation Division, Bahraich and Shrawasti Forest Divisions in Uttar Pradesh were devoid of tiger. Thirteen corridors that potentially connect these nine blocks have been identified. When connectivity with the Nepal side is taken into account, the nine THBs can be pooled into five larger units (referred as Tiger Units, TU). Among these, TU II, which is in the bhabar tract and includes Corbett TR, is the most intact one. TU IV (Pilibhit FD-Suklaphanta Reserve-Kishanpur WLS-Dudhwa NP- Bardia NP-Katernighat WLS) is the most extensive terai habitat. Each piece of habitat and connectivity in these Units are crucial and at the same time, are threatened by anthropogenic pressures. Ungulate distribution and relative abundance in TAL corresponds to the high variation or heterogeneity in habitat features. However, the overall status of prey (ungulate) availability is reasonably better in this Landscape, largely owing to the interspersion of Protected Areas between Reserve Forests. The evidence is clear that tiger distribution and its abundance are linearly related to wild ungulate prey such as chital (Axis axis) that has wider spatial distribution. Sambar (Cervus unicolor) and wild pig (Sus scrofa) also contribute substantially in deciding the occurrence of tiger in bhabar and terai regions respectively. The domestic dog was identified as a reliable indicator of disturbance that impedes tiger occurrence. Undisturbed hilly (bhabar) areas such as Corbett TR, which usually have many deep nallahs, providing hideouts and abundant prey (sambar, chital and wild pig) support substantial population of tiger. The terai tall grass habitats, which provide adequate cover, as in Kishanpur WLS and Dudhwa NP, with prey such as chital, pig and swamp deer, is the second best. It appears that in a few years time, tigers may cease to exist in habitats like Sohagibarwa-west (THB VIII), an isolated habitat patch in Uttar Pradesh, which is under enormous anthropogenic pressures. Leopards tend to avoid terai habitats and high-density tiger areas, but are still common in areas extirpated of tiger. Data from the Census of India 1991, for 33 tehsils (units of District) within the study area, indicated that the bhabar, largely west of Sharda river, had significantly lower human density (334/km2) and higher percentage of forest cover (36%). The corresponding figures for terai (east of Sharda river) are 436/km2 and 17% respectively. It appears that the bhabar areas, at present, are in a better position to buffer firewood dependency of the people. Human population increase, ever growing habitat encroachments, poaching, firewood extraction and bhabar grass (Eulaliopsis binata) collection for rope making, stealing of tiger and leopard kills, and boulder mining causing enormous disturbances and fragmentation are the major problems identified. The extensive empirical information (distribution and abundance) collected on vegetation parameters, ungulates and tiger can be used as baseline data to initiate monitoring programmes. In addition, the monitoring should include establishment of adequate number of one-hectare plots and line transects for periodic evaluation of habitat conditions and prey abundance respectively. The study recommends that Chilla-Motichur and Gola river corridors should be established on priority basis and the conservation status of THB IV containing Suklaphanta Wildlife Reserve-Pilibhit FD-Kishanpur WLS should be strengthened. If done, the former will constitute the largest (ca. 8000km2) tiger and elephant habitat anywhere along the foothills of the Himalaya and the latter will ensure the future of one of the finest terai habitats (ca. 1200km2). Initiation of a conservation programme like establishing Rajaji-Shivalik Tiger Reserve is urgently needed to eliminate boulder mining in Yamuna river to ensure the ranging and occurrence of tigers between Shivalik FD and the Kalesar-Simbalbara forests, the western most limit of tiger distribution range. Raising of fuel wood plantations with community participation, use of fuel-efficient chulas, resettling of gujjars (migratory pastoralists) and eight key villages, shifting of one factory and weaning people from bhabar grass collection and conservation education programmes are also recommended. There was a consensus in the two-day workshop held on 6-7 November 2003 in WII that the Nepal model, with a strong scientific foundation and involvement of local people, needs to be adapted for the Indian side of TAL. Cross border cooperation between India and Nepal is a must to ensure the long-term conservation of tiger and its habitat in this LandscapeItem Study on ecological and socio-economic impact of invasive species, Prosopis juliflora and Lantana camara and their removal from forest, common and fallow land of Tamilnadu(Wildlife Institute of India, Dehradun, 2018) Sivakumar, K.; Rawat, G.S.; Badola, Ruchi; Adhikari, B.S.; Kamalakannan1) Prosopis juliflora is an invasive, drought resistant, evergreen fast growing pheratophyte widely distributed in India and also in arid and semi-arid tropical countries. It is a highly valued wood source for rural people in India. The P. juliflora is believed one of the worst invaders affecting natural and man-made ecosystems and its local biodiversity in Tamil Nadu. In this context, this study was conducted aimed to assess the distribution patterns of P. juliflora and its impacts in three different agro-climatic zones of Tamil Nadu. 2) In 1959, Prosopis juliflora was introduced in Tamil Nadu to meet the fuelwood requirements of the rural poor people and to re-vegetate the degraded lands but it spread at faster and occupied almost all agro-zones of Tamil Nadu. In India, P. juliflora was considered as one of the worst invaders in the country affecting natural ecosystems and local biodiversity. In order to eradicate this species from natural forests, preparation of a restoration plan is desirable with knowledge on ecology and impacts of P. juliflora in Tamil Nadu. Keeping this in view, Wildlife Institute of India with support of Tamil Nadu Forest Department assessed the extent and abundance of P. juliflora in forest, common and fallow land of Tamil Nadu. Initially, the study was started in the southern zone of Tamil Nadu and later in other agro-climatic zones of Tamil Nadu (i.e. Cauvery delta zone (Nagapattinam district), Southern zone (Ramanathapuram district) and Western zone (Sathiyamangalam Tiger Reserve, Erode district). 3) Totally ninety transects were laid randomly in three agro-climatic zones of Tamil Nadu. Each transect of 2 km length, it had six 15 m radius plots at equal distance of 400 m to quantify the environmental parameters such as vegetation structure and composition, cover percentage of grass, native herbs, weeds, animal pellet and bird abundance, etc., was recorded by using standard methods on the same transect. Influence and impact of Prosopis juliflora and its and socio-economic status were assessed by using a questionnaire survey in entire taluks of three agro-climatic zones. 4) The results revealed that occupancy of Prosopis juliflora was more in the southern zone compared to the other two zones. Southern zone occupies 79.4% of Prosopis juliflora invaded in this region than western zone (46%), and in Cauvery delta zone (32%). Density (F = 34.35, P < 0.05) and frequency occurrence (%) of P. juliflora were also higher in the southern zone followed by western zone and Cauvery delta zone. The richness and native biodiversity of plants and related herbs, shrubs were highly ruined in southern zone followed by Cauvery delta and western zone. The highest extent of Prosopis was observed in the entire seven taluks of the Ramanathapuram district (southern zone) compare to the Nagapattinam taluks (Cauvery delta zone) and Sathyamangalam Tiger Reserve ranges (western zone). Except Prosopis juliflora and Lantana camara; Parthenium hysterophorus and 2 Chromolaena odorata caused huge smash up to the native ecosystems in some ranges of Sathyamangalam Tiger Reserves. 5) In Ramanathapuram district, the abundances of herbs such as Tephrosia purpurea, Crotons sparsiflorus, and Cleome viscosa were significantly lesser in P. juliflora invaded plots as compared to the non-invaded plots. Relative abundance of birds such as Pavo cristatus, Conturnix conturnix and Acridotheres tristis were positively correlated with P. juliflora abundance in Ramanathapuram taluks. The western zone where the habitat dominated by P. juliflora was observed with low abundances of wild ungulates. 6) Driest environment settings of southern zone favored more P. juliflora than other two agro-climatic zones that are comparatively wet. 7) The study found that the impact of Prosopis in the forested landscapes of Tamil Nadu, especially in Sathyamangalam Tiger Reserve seemed to be adversely affecting the distribution of native biodiversity. 8) Dry zone of Tamil Nadu i.e. at Ramanathapuram the groundwater level-soil moisture conditions, humidity and temperature under the canopy cover were better in the habitats dominated by P. juliflora but in the forested landscapes such as in the Sathyamangalam TR, these environmental factors were comparatively lesser than other habitats of the zone. It reveals that P. juliflora in the forested landscape is not good for natural environmental settings as well as the biodiversity of the region. 9) In all zones that were studied in Tamil Nadu, the P. juliflora was observed to be allelopathic that discouraging other plants from growing around them and seems to be toxic to other biotas in ways that allow the invasives to monopolize the space, sunlight, and nutrients at the exclusion of other species. Plant diversity was observed significantly low at P. juliflora dominated habitats than other habitats of Tamil Nadu including in the Ramanathapuram District. In the native habitats of P. juliflora, the other species have developed a mechanism to counter the allelopathy of P. juliflora, but such defense seems to be not available to several native plants of Tamil Nadu. 10) The study could not find any significant impact of Prosopis juliflora and Lantana camara on the productivity of agricultural crops grown adjacent to the dense growth of Prosopis juliflora and Lantana camara on the bund or as a pure stand. 11) Prosopis juliflora, which is adapted to survive and thrive in diverse environments including very harsh dry environments, was a major boon for impoverished people subsisting in the Ramanathapuram District as it provides 3 them with badly needed valuable provisional services; fuelwood, charcoal, animal feed, constructional materials, reclamation of degraded soil, etc, but the Prosopis juliflora was observed to be adversely affecting both environments as well as native biodiversity in other zones of Tamil Nadu. 12) It was found that wetlands in the arid region are highly susceptible to Prosopis invasion and these wetlands were once used by migratory birds in large numbers but not nowadays that is might be due to high abundances of invasive species. 13) Although, alien invasive species such as P. juliflora and L. camara are adversely affecting the native biodiversity especially in the Western Zone and Cauvery Delta but it has livelihood values in the Southern Zone especially Ramanathpuram and adjoining districts of Tamil Nadu. 14) The study also found that the available nitrogen, phosphorus and organic carbon in the soil were high in highly invaded areas compared to less or non-invaded sites especially in the Southern Zone. 15) Economic analyses also revealed that the benefits of the P. juliflora invasion in the southern zone are higher than the costs. However, some aspects such as increased risk of water table and long-term ecological changes were not examined, thus making the total economic valuation incomplete. 16) P. juliflora and L. camara spread can be halted by actions such as clear cutting/up-rooting followed by burning of the stump of P. juliflora and keeping up-side down of stump of L. camara. Alternatively, ways can be found to utilize the existing stands of P. juliflora so that frequent harvesting can exert a check on its expansion in the non-forested landscape. Minimum, 10 years of weed management plan should be made mandatory of all Management Plans of all Protected Areas and other reserve forests of Tamil Nadu to successfully halt the expansion of these invasive species so that the native biodiversity are conserved. 12) The study concludes that complete eradication of P. juliflora and L. camara is inevitable in the forested landscapes and Protected Areas of Tamil Nadu. However, the study recommend that sustainable management and control of P. juliflora may be a better solution than eradication in the Southern Zone.
