M Sc Dissertation(WII)

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    RISK ASSESSMENT OF POTENTIALLY TOXIC ELEMENTS IN THE HABITAT, AND DIET OF SMOOTH-COATED OTTER (Lutrogale perspicillata) IN TUNGABHADRA OTTER CONSERVATION RESERVE (TOCR), KARNATAKA
    (Wildlife Institute of India, Dehradun, 2024) Ahmed K., Niyaz; Johnson, J.A.; Hussain, S.A.; Sah, Ruchika
    Smooth-coated otter (Lutrogale perspicillata), is a vital indicator species for freshwater ecosystems, playing a crucial role in maintaining ecological balance. Despite their essential place in the food web, they are always neglected compared to other terrestrial carnivores. This study explores the distribution, diet, and, ecotoxicological exposures to smooth-coated otters in Tungabhadra Otter Conservation Reserve, Karnataka. The study area, encompassing a 36km stretch of the Tungabhadra River (TOCR), is a unique habitat facing significant anthropogenic pressures, including mining activities and pollution, which threaten the local biodiversity and otter populations. The distribution of smooth-coated otters in TOCR was assessed through intensive sign surveys, revealing a clumped distribution pattern. Otter signs, including spraints, pugmarks, and grooming sites were dominant signs found in the landscape. Dietary analysis was examined by analysing the spraints (scat), using two methods frequency of occurrence method, and the score bulk estimate method revealing a predominantly piscivorous diet. The diet consisted of about 14 species out of which 69.53% is constituted of non–native fish species (Oreochromis mossambicus, Labeo rohita, Cyprinus carpio, and Cirrhinus cirrhosus). Ecotoxicological assessments were performed on water, sediment, fish, and spraint samples to evaluate the presence of potentially toxic elements (PTEs). While PTE concentrations in water and sediment were generally below harmful thresholds, their presence poses a long-term risk through bioaccumulation. Risk assessment indicated significant potential health risks from metals like mercury and arsenic, which could impact otter heal
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    Resource Use and Distribution of Smooth-Coated Otter (Lutrogale perspicillata) in the Sub-Himalayan Foothill Rivers of Uttarakhand
    (Wildlife Institute of India, Dehradun, 2019) Basak, Sayanti; Hussain, S.A.; Gopi, G.V.
    Otters are the apex predators of the wetland ecosystems they inhabit. Being sensitive to both pollution and habitat destruction, the presence of otters in a wetland ecosystem, be it rivers, lakes, swamps, mangroves or estuaries, indicates the occurrence of a viable prey base, thus indicating an ecologically healthy condition of such ecosystems. Coupled with habitat, prey is one of the major factors that limit species populations. Many species, including otters, are often seen to cope up with disturbed surroundings only for the easy accessibility or abundance of prey in those areas. The aim of this study was to understand the ecology of Smooth- coated Otter (Lutrogale perspicillata) in terms of their habitat requirements, food habits, and distribution across the landscape. The study was conducted in select rivers of Rajaji National Park and Tiger Reserve, Lansdowne Forest Division, and Corbett National Park and Tiger Reserve. These protected areas fall in sub-Himalayan region, a region of high biodiversity value threatened by immense anthropogenic pressure. Habitat parameters were measured at every 250 m along a river bank and also in locations where there were otter evidences. The importance of different habitat parameters influencing otter occurrence were analysed using Generalised Linear Models (GLMs) and non-mapping technique using Bonferroni confidence interval approach. Smooth-coated Otter significantly preferred deep pools with moderate to sparse bank-side vegetation during the mid-winter and late-winter season. Moderate width water bodies are preferred over narrow water bodies. Muddy and sandy bank substrate types were preferred. Rocky stretches were largely avoided. Water body type i.e. pools and bank substrate type, i.e. rocky substrate, are the significantly influencing factors on otter distribution. Feeding habit of otters were studied by analysing 120 spraints collected throughout the study area. In this study, we also explored how the habitat suitability modelling could predict the percentage of area and a gradient of environmental conditions suitable for the occurrence of Smooth-coated Otter across the study area. MaxEnt modelling was used to predict habitat suitability of Smooth-coated Otter across the landscape. The most important variables affecting otter distribution were compound topographic index, Euclidean distance from the river, and slope position index. With increasing distance from water, and increasing slope, the suitability of an area to sustain otter populations decreased.
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    Effect of habitat characteristics on waterbird diversity along river ganga in Allahabad, Uttar Pradesh
    (Wildlife Institute of India, Dehradun, 2017) Kumar, Ankit; Gopi, G.V.; Hussain, S.A.
    Riverine floodplains are a mosaic of different habitat available in the riverine area. It is extensively used by an array of flora and fauna. It supports a huge biodiversity by providing habitat as a resource to various taxa. Many waterbird species are directly and indirectly dependent on the riverine floodplains and use riverine habitat at a certain stage in their life cycle. The area also supports a high diversity of wintering waterbirds. Migratory bird takes refuge in the area during the severe winter in their native habitat. Habitat-specific species use different types of habitat present in the riverine floodplain. The riverine system also has an intricate relationship with the humans. Since a long time, these habitats are subjected to overexploitation that affects the natural ecological processes and the functioning of river. Degradations of floodplains of the major rivers of the world by alteration of water flow, encroachment in river islands and collection river bed materials, discharge of urban and industrial effluents, are threatening the biodiversity of rivers and their associated wetlands. The effect due to different levels of the disturbance is unknown on the diversity and abundance of waterbirds. On these lines, I conducted my study focused on identifying what are the habitat characteristics which is affecting the abundance and diversity of waterbirds and what are the anthropogenic factors affecting its diversity and abundance. The study was carried out in Allahabad District of Uttar Pradesh. It is known for the confluence of two major rivers of India, river Ganga, and its tributary river Yamuna
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    Diversity and abundance of birds in disturbed and undisturbed wetlands of Manipur river basin
    (Wildlife Institute of India, Dehradun, 2017) Sharma, Sijagurumanyum Rohikanta; Hussain, S.A.; Nair, Manoj V.; Tuboi, Chongpi
    The Northeast (NE) Indian region is one of the hotspot of Indo Malayan biodiversity that remains largely unexplored. For this study, two wetlands in the NE Indian region of Manipur, viz Keibul Lamjao National Park (KLNP) and Pumlen pat (PP) were selected as the study site. Diversity and abundance of bird species in the region were assessed because of their prominence in the landscape. Conservation measures are needed for both the sites In tenns of these threatened bird species. Site-specific management strategies need to be incorporated in the management plan for the management of the isolated local populations of Black-breasted Parrotbill and Yellow-breasted Bunting in the undisturbed site (KLNP). Whereas some legal conservation measure is needed for conserving threatened grassland birds in the disturbed site (PP). It is also mandatory to monitor the population of Yellow-breasted Bunting population discovered from both the sites.
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    Riverine Habitats Under Changing Land-use : A Resource Selection Study of Smooth-Coated Otter (Lutrogale perspicillata Geoffroy Saint-Hilaire 1826) in Kabini River and Tributaries
    (Wildlife Institute of India, Dehradun, 2015) Aneesh, C.R.; Hussain, S.A.; Johnson, J.A.; Talukdar, G.
    Habitat selection is an important part of the ecology of semi-aquatic mammals since they are highly specialized animals. River otters are especially vulnerable animals in the present situation due to increasing human disturbance, altering riparian vegetation damming and channelization in river basins. This study looked at the effect of land-use pattern on the habitat selection by otters with special reference to smooth-coated otter (Lutrogale perspicillata) in Kabini river, South India. The study showed fewer presence sites of smooth-coated otter inside the protected areas, due to naturally unsuitable habitats for the species, with shallower stream habitats in hilly terrains. These sites were occupied by Asian small-clawed otters (Aonyx cinerea). However the sign intensity was more in presence locations inside protected area and least in urbanized area. The detailed study in presence only sites revealed that anthropogenic disturbance primarily increasing human presence, fishing and grazing is the most important factor affecting selection of habitat by smooth-coated otter. The intensity of usage of habitat is also governed by disturbance factors. Other environmental factors are only secondary to disturbance factors affecting habitat selection which includes a set of factors pertaining to land and water summarized as slow, deep waters with intact bank cover and/or grassy banks with close escape cover distance. Prey fish species of medium size class (21-40cm) affects the habitat selection. Although Asian small-clawed otter and smooth-coated otter occur in same river system , there is a clear niche partitioning between these two species. The study also Looked at the effect of dams on otters which is the primary factor negatively affecting otter habitats. Yet flow regimes are mostly compensated due to more streams joining the main river channel. Increasing degree of habitat disturbance in different land-uses seems to negatively influence the fluvial functionality which is positively associated with otter habitat. The combined effect of isolation due to reservoir and increasing disturbances in downstream area pushes smooth-coated otters to select habitats upstream that are marginal to them and more suitable for small-clawed otters.
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    Resource Selection and Conservation of Smooth coated otter Lutrogale perspicillata in and Around the Coringa Wildlife Sanctuary, Andhra Pradesh
    (Wildlife Institute of India, Dehradun, 2015) Prasad, Nadendla Leela; Sivakumar, K.; Johnson, J.A.; Hussain, S.A.
    Resource selection of Smooth-coated Otter Lutrogale perspicillata was studied in the Coringa Wildlife Sanctuary, where a two dimensional interface of fishermen-otter present: fishermen fishing in the habitat of otter and otters feeding in the aquaculture farms of fishermen. This is resulting in conflict between Otters and Humans in the region. In this context, this study was carried out to understand the extent of this conflict by studying the food habit of otters and ecological factors that could affect the otter distribution in this mangrove ecosystem. 2. The study was carried out from December 2014 to April 2015 in and around the Coringa Wildlife Sanctuary, which is located at the mouth of the Godavari River, in Andhra Pradesh. 3. Food habit of otters was studied by analysing their spraints that were collected from different parts of the Sanctuary. Habitat and distribution of otters were studied using belt transacts along creeks as otters mostly used banks of the creeks. Further, people perspectives towards otter and intensity of human-otter interface was studied using interview based questionnaire surveys. 4. It was found that the fishes cultured in the aquaculture farms were not present in the creeks of Coringa WLS. 6. The diet analysis of 81 spraints collected from December 2014 to March 2015 revealed that fish comprise of 99% of Smooth coated Otter diet. Of this major portion comprised of Mystus gulio, Oreochromis mossambicus and Liza tade. These species were also found in high abundance during the fish sampling from which relative abundance was calculated. This indicates that Otters in the sanctuary are opportunistic feeder rather than selective. 7. Mystus gulio (long whiskers catfish) found to be the major prey of otter in the Coringa . WLS, constituting 17.8% of weight of all food items found in the spraints and this fish was also eaten by many otters (found in 13.4% of spraints). M gulio was also the most common fishes of the Sanctuary. M gulio followed by Oreochromis mossambicus (Tilapia) constituting 14.6% of weight of all food items found in the spraints. 9. Although, all five major aquaculture species offish were found in the spraints of Otter but overall, the aqua farm fishes constituted only the 14.4% of weight of total foods items found in the spraints of otter. Of the total spraints collected, only 17.8% of spraints contained the aqua farm fishes and remaining 82.2 % otter spraints did not have. aqua farms fishes and these otters were seems to be eaten only the wild fishes. 10. The high abundance of invasive tilapia was found in the Ramannapalem creek, which is a less saline creeks adjoining with aqua farms and villages. This fish was the second most preferred diet of otters in the area. This fish breeds in the grasses that are at the banks of creeks. Breeding tilapia was a easier target for otters and therefore, otters were seen close to aqua farms. 11. The factors essential for Otter survival in were found to be more towards land and decrease with increasing distance from land. An ordinal regression model with sign intensity in three ranks revealed that the factors that are playa significant role in Otter distribution are distance from sea had a positive effect on Otter distribution (estimate = 0.403, Standard error =0.225 and P value= 0.073), Width of channel also had a positive effect to an extent (estimate =0.509, Standard error =0.273 and P value = 0.062). Depth of the creek had a negative effect (estimate= -0.624, Standard error = 0.322 and P value=O.053). 12. As the factors that are positively influencing Otter distribution are near villages Otters signs were also found highest in creeks near villages. Thus it was concluded that the presence of Otters mostly towards villages is probably due to presence of suitable habitat near villages rather than fish from aquaculture farms. 13. Fishermen's Traditional Ecological Knowledge of Otters in and around the Coringa Wildlife Sanctuary had also confirmed that otters largely feed in the wild but visit aqua farms occasionally for food or to play. Further, about 79% of people in the region felt that Otters visit their farms at night that confirms the nocturnal behaviour of Otters around human habitation, which is supported by previous studies 14. Further, most of fishermen (75%) believed that otters are high threat to aquaculture when compared to fishing cat and jackals. This is due to group hunting behaviours of otters, whereas fishing cats and jackals visit aquaculture ponds solitarily 15. Interestingly, nearly 11 % of fishermen felt that Otters have caused an income loss of 1-5% followed by 9% of respondents who claimed a loss of 10-30%. But, few farmers (2%) felt that Otters cause nearly 30-50% of loss, who were in the low income group and who can not offer even small loss in income. 16. Generalized Linear Model (GLM) with Poisson distribution revealed that both income and education of fishermen positively influenced their perspectives towards conservation importance of otters in the region. 17. Majority of fishermen (65%) believed that there was a decline in the sightings of otters and they have also believed that the population had been declined in the region. However, in contrast, about 13% of them felt that there was an increase in Otter population over years and most of these respondents who have also believed that high loss of income due to otters visits to their aqua farms. 18. Most of the aqua-farm owners admitted that they always scare and chase away otters when they visits their farms. Though only 11 % of them opted for killing does not mean that people have a positive attitude towards Otter. Boxplot analysis to understand the relationship between people's action towards visiting otters to their farms and their income and education, has revealed that the farm owners who had less income have tried to kill the visiting otters due to their poverty. 19. This study found that fishermen with poverty could not bear even the meagre loss caused by otters to them. Further, the study found that less educated people against the otters in the region. Therefore, additional livelihoods and awareness education to those poor fishermen need to be provided for the long term conservation of otters in the region. EGREE Foundation of Andhra Pradesh, a foundation established with support of GoI-UNDP-GEF Project to sustainably manage the Godavari estuarine has already initiated some programme in this regard but their programme should focus more on fishermen who are with low income 20. It is also proposed to have otter proof fencing for aquafarms especially those farms located along the Ramanapallam creeks. Developing eco- tourism in the sanctuary with the involvement of fishermen and small scale farm owners can also change their attitude towards otters.
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    Density Distribution and Factors Influencing Sea Stars in Selected Islands of Lakshadweep India
    (Wildlife Institute of India, Dehradun, 2013) Jayaram, Sharmila; Hussain, S.A.; Gopi, G.V.; Apte, Deepak
    Coral reefs are the most fragile, complex and diverse ecosystem on earth. But recently, they arc under severe threat due to both natural (climate change, storms and disease outbreaks) and anthropogenic factors (overexploitation, coastal developmental activities and pollution). As evident from earlier studies, a major factor causing degradation of coral reefs is due to an asteroid species belonging to phylum Echinodermata which is considered second to storm damage. Thus to analyze the condition in Lakshadweep Islands I assessed the density of asteroids in four Islands of Lakshadweep. It was found that the five species detected belonging to three families (Oreasteridae, Linckiidae and Acanthasteridae) were having varied density across the four islands. Overall density estimates of the asteroids ranged from 0.05(S.E = 0.02) to 0.80(S.E = 0.09) per 250 square meter. The asteroid density was highest in the uninhabited Island named Bangaram. Correspondence Analysis (CCA) showed that major gradients in environmental variables influenced asteroid species distribution. Sample scores on ordination ' axis 1 were strongly correlated with water pH, water depth and dead coral. Out of the three strongly correlated environmental variables pH was found to be the most ecologically important variable that affects the asteroid distribution. Corallivorous asteroid population outbreaks are becoming a boon to the coral reef ecosystem all over the world and contribution of water pH variation of this outbreaks are being studied well. Thus management strategies in Lakshadweep Islands that 'accounts the variation of water pH are required to conserve the coral reef ecosystem.
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    An Assessment of Recreational Value of Periyar Tiger Reserve and the Distribution of Tourism Income Among Stakeholders
    (Wildlife Institute of India, Dehradun, 2013) Sebastian, Subish; Badola, Ruchi; Hussain, S.A.; Uniyal, V.K.
    Protected Areas (PA) are cornerstone for biodiversity conservation and their role in maintaining flow of ecosystem goods and services is now being acknowledged. But it is difficult to justify their creation when demand for employment, infrastructure increases, and thus government may take decision looking at the short term economic prosperity. When economic wealth generated through development activity and compared to the income generated from P A, the former does over shadow the income generated from P A conservation. But in doing so, the other benefits of conservation remain unaccounted. These benefits range from provision of fuel, fodder, food, to local communities at local scale, and provision of clean water, air purification, and aesthetic and bequest value at regional or larger spatial scales. Accounting of the services such as recreational value provided by the P A can help generate support for conservation at all spatial scales. The Periyar Tiger Reserve (PTR) is a popular tourist destination visited by the people by national and international tourists. Ecotourism programs are implemented in PTR as an integrated conservation and development project for sustainable development of local communities, and to create awareness as well as to promote conservation. The success of this program can be largely attributed to its charismatic flagships species and its unique water safari where tourists can enjoy the wildlife in scenic background on either side of the Periyar Lake. Encouraged by the success of tourism, more and more communities have enrolled themselves in different activities which are either directly or indirectly connected with tourism. Being the most visited and popular P A, it becomes imperative to explore the recreational value of the PTR. Also, since local communities living in and around PTR are traditionally dependent on the reserve's resources and are being involved in ecotourism activities, it is essential to assess the distribution of ecotourism benefits stakeholders. It is well known that support for conservation can be generated if the communities are obtaining benefits from conservation linked tourism. But the monetary leakages in community based tourism or ecotourism often undermine the support for conservation. Thus, PTR being an ecotourism site, it is crucial to know the monetary leakages occurring onsite in PTR and how this revenue related linkages and leakages mould the attitude of stakeholder towards biodiversity conservation? The recreational value of PTR was calculated using the Zonal Travel Cost Method. This method helps to derive the demand function for the site. Questionnaire survey was carried out to know the socio-economic status, the monetary flow in the household; examine people attitude towards PTR. One hundred twenty five in-depth interviews were conducted among eight major stakeholders whose dependency on tourism was very high. For assessing the best existing model which underlines the principles of ecotourism, the tourism was classified into three kinds, first one Tourism run by private party, secondly Tourism run by local community, and finally Tourism run by Periyar Tiger Reserve's EDCs. The recreational value of the reserve was estimated as Rs. 44176299.32. With the cost per visitor being Rs. 63.56 the consumers' surplus was large, showing the willingness of visitors to pay for wildlife recreation. The socio economic study reveals that the 'Tourism Programs' run by EDCs are the best models providing 100% share to local communities, followed by the home stays run by local communities. Monetary leakages were highest in case of resorts (82%), followed by 20% leakages from home stay, while no leakage was observed at EDC. The leakage of 200/0 is due to the link with foreign players like tour operators and other resorts who market their products. Even though resorts that the private player run programs claim as ecotourism, only 14.9% of share goes to the local community. The results obtained indicate that the conservation attitudes are not influenced by income class, education, gender and age of the respondents. Attitude of local community is highly Positive towards forest and wildlife conservation, which can be attributed to the benefit sharing approach developed by Forest Department. The findings indicate that the participatory approach and benefit sharing are good means to promote sustainable use of natural resources. High consumer surplus for visits to PTR suggests that recreational value of PTR is higher than the current expenditure by the people. Thus, there is a poss~bi1ity of increasing the ecotourism. fee, which would contribute to higher turnover for the forest department. Tourism income is not equitably distributed among stakeholders. The percent of locals employed in profitable ecotourism ventures was less, resulting in 82% monetary leakages. Support for conservation is very high among all stakeholders in PTR but this scenario or this state can't be clearly attributed to the benefits derived from the tourism. Forest department play a major role in creating awareness. Conflict among stakeholder group about the revenue sharing and the mode of aggressive marketing does not affect their perception about wildlife. Occupation does not affect the attitude of stakeholders. Benefits derived from tourism lead to positive attitude of local communities and enhance conservation support among local communities. Higher employment of locals in the resorts, massaging parlours and as taxi and tour operators would lead to sustainability of ecotourism in PTR. Capacity building and financial assistance to the locals would enhance local employment and minimize monetary leakages and thus increase benefits to the locals.
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    Relative sensitivity of mammalian carnivores to disturbance in sub-tropical forests of Arunachal pradesh
    (Wildlife Institute of India, Dehradun, 2005) Dada, Tamo; Hussain, S.A.
    Study the impacts of disturbance such as clearing of forests for habitation, presence of domestic livestock, forestry operation such as logging and extracting of non-timber forest products, trapping and hunting for sustenance as disturbance on carnivore populations. The study was conducted in the low land semi evergreen forests of Pakke Tiger Reserve, Arunachal Pradesh. For this study following objectives were identified • Prepare an inventory of carnivore species occurring in Pakke Tiger Reserve. • Study spatial and ecological distribution in terms of disturbances and environmental variables respectively. Four study sites, Khari, West bank, Dicho and Lanka were selected from within the Pakke Wildlife Sanctuary and adjoining Papum Reserve Forests, on the basis of various parameters which might have affected the habitat structure of the area. The influences of habitat variables on the occurrences of carnivore species were examined by using Classification tree analysis by using S-PLUS 4.5 software. The final output showed that, distances from village was the most important variable that determines the presence - absence of civets .Civets were absent in areas with more than 65 % shrub cover .Small cats occurred in areas with greater shrub cover and shrub height The occurrence of small cats decreased with the distances from village increased '. Small cat occurred low in areas with high canopy cover.
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    Dead Wood, Wildlife and Protected Area Management A Study on the Extent of Use of Dead Wood by Wildlife in Periyar Tiger Reserve, Kerala, India
    (Wildlife Institute of India, Dehradun, 2003) Susaant; Hussain, S.A.
    Dying, dead, and down trees form an integral component of forest ecosystems. They not only serve as critical microhabitats for many species, but also they are large reservoirs of organic matter and hence play a pivotal role in nutrient cycling. There are whole groups of organisms, which use and need dead wood for their survival in any forest ecosystem, ranging from conspicuous, well-known creatures like flying squirrels and owls to large numbers of invertebrates, fungi, lichens, mosses, and vascular plants. And not only these, there are microorganisms that exploit the pool of organic matter and nutrients deposited in the woody debris on the forest floor. Thus it becomes crucial to examine and study the wildlife use aspect of dead wood. In recent years, the subject of 'decaying wood' has become a major . conservation issue in managed forest ecosystems. This holds true for the Indian scenario as well, where disappearing forests and their far reaching consequences are a major focus of concern. The situation worsens in areas where extraction of different forms of dead wood from the existing forested areas . by local communities living in the vicinity goes unabated. Critical ecosystem functions of dead wood, coupled with incomplete knowledge for management, make the topic of decaying wood a priority for future research and adaptive management. Unfortunately, there is scanty work done in India on this issue. This short-term study was conducted in the Periyar Tiger Reserve, Kerala, from December 2002 to April 2003. The study focused primarily on following objectives: 1) To quantify the abundance of different types of dead wood in different forest/habitat types. 2) To relate dead wood abundance to live tree abundance. 3) To quantify the extent of use of dead wood by different vertebrate taxa particularly by reptiles, birds and mammals. An initial period of 15 days was spent in field for reconnaissance during which two different types of forests, namely Semi evergreen forest and moist deciduous forest were identified. Six areas were chosen in the forests around Edappalayam and Mullakudy such that each area had adjacent patches of semi evergreen forest and moist deciduous forest. The rationale behind this was that the disturbance levels in both the forest types within each of , the areas would be nearly equal. Three areas were categorized as disturbed and the rest three as undisturbed based on movement of people through these areas. After few trials 30 x 30 m plots were used in conjunction with short transects across the width of each forest patch to sample for different dead wood densities. In total 54 ha area was sampled in Semi Evergreen and Moist Deciduous Forests which is ca. 0.55 percent of the total range area. Tree densities were also estimated in the forest patches to relate with dead wood abundance. In the lake habitat eight stretches of 1 km each, with a gap of 0.5 km between successive stretches, were chosen for counting number of dead wood in water as well as shores in the high and low water level seasons.