M Sc Dissertation(WII)
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Item Nutritional Ecology of Asian Elephants (Elephas maximus) in Chilla Range of Rajaji National Park, Uttarakhand(Wildlife Institute of India, Dehradun, 2009) Datta, Suniti Bhushan; Goyal, S.P.; Sathyakumar, S.Responses of animals to the habitat has been the central focus for management of species and of these aspects, nutritional ecology has been the key issue in foraging behaviour studies and habitat studies. Therefore, the study focused on the nutritional aspect of forage selection by Asian elephants (Elephas maximus) in Chilla Range of Rajaji National Park. The main objectives were to determine whether habitat structural heterogeneity or nutritional quality of the selected food plant species was a determinant in the temporal and spatial habitat use by elephants and to determine the reasons behind seasonality in foraging. The study area of 148km2 in Chilla Range of Rajaji National Park was divided into twelve 2x2km grids, and these were further divided into 4 sub-grids each. In each sub-grid, a 1 km long line transect was laid and along this 10m radial plots were placed at 100m intervals. Vegetation data were collected to characterize the habitat structural heterogeneity in terms of number of trees of each species, height of canopy base, canopy volume, percent canopy cover, species diversity, species density and geo-spatial variables such as NDVI, standard deviation of slope, mean elevation and the proximity to water. Parts of 12 most-preferred plant species were collected in the study areas for estimating nitrogen, ash, acid detergent fibre, and macro and micro minerals such as sodium, potassium, calcium, copper, magnesium and zinc. During the study period from December 2008 to May 2009, Elephant response was determined in terms of dung density along the 1km transect in winter and in summer. The total number of trees in each grid varied from 124 to 268. Tree diversity ravged betweel) 0.456-1.454. Height of canopy base was mostly 1.5-3.0 m, although two grids showed extremely high canopy bases. Canopy volume ranged from 165.63m3 to 948.36m3 , although the majority of the grids showed a high variation in canopy volume in terms of standard deviation (SE). The percent canopy cover ranged from 54.13% to 93.72%. Most of the NDVI values were _high in the study area (>0.180), while one grid showed a low value of 0.143. For the standard deviation of slope, the values ranged from a low of 2.46 to a high of 8.46. The mean elevation of the study area ranged froin 391-840m a.s.l. Nutritional values estimated for most of the parameters in winter and summer from selected plant samples collected in the study area showed slight variations 4 between seasons. Percent nitrogen content indicated no seasonal difference (f=0.98, p=0.05, df=ll). The percent acid detergent fibre indicated a difference (P<0.05,df=I I) between the two seasons. Percent ash content was found not significantly different (p=O.l6, p=0.05, df=l1) between seasons. Amongst the macro and micro minerals, sodium content was significantly different across the two seasons. Potassium content was found to be significantly different across the seasons (p<0.05). Calcium content was also found to be significantly different between winter and summer (P<0.05). The copper content could not be compared across the seasons as in summer the levels present in plant samples were too low to be detected by the instrument. The difference in magnesium and zinc content across the two seasons were not significant (p=0.16 and P=0.31). Dung density in the grids across both seasons was non-uniform and highly skewed (p<0.05, df=47). The dung densities in both seasons were related more with the habitat heterogeneity variables than nutritional values obtained in each grid. The relationship between dung density and the number of plants was positive in the winter seasons (R2= 0.2848) and summer (R2= 0.4383), indicating that elephants are highly selective towards areas with higher numbers of woody plants. Plant species diversity indicated no influence on dung density in winter (R2= 0.00005), but showed a negative trend in summer (R2= 0.0154). The height of canopy base was negatively related to dung density, with elephants selecting areas with a mean canopy base height between 1.5-3.0m during both winter (R2=0.2288) and summer (R2=0.174). Dung density showed a negative trend when related to canopy volume in both seasons. The R2 value for winter is 0.2087 and in summer it is 0.1471. Percent canopy cover had a negative influence on the dung densities in winter (R~= 0.083) and in summer (R2= 0.1524). NDVI showed a negative relationship with dung densities in winter (R2=0.01l1) and a positive relationship in summer (R2= 0.1894). The relationship between the standard deviation of slope and dung density showed a negative trend in both winter, (R2=0.0033) as well as in summer (R2=0.0389). The higher elevation grids show a lower d/mg density during both winter (R2=0.216) and summer (R2=O.l443). The relationship between dung density and proximity to water in winter is negative (R2=0.1575) and the relationship remains negative (R2=0.1016) in summer. In relation to nitrogen content and dung density in winter there was a weak positive trend (R2=0.0256), while in summer there was a weak negative trend (R2=0.032). The relationship between dung densities and percent acid detergent fibre (ADF) in winter indicated a weak positive trend (R2=0.0012) and during summer, indicated a weak negative trend (R2=0.0657). In relation to percentage ash content (Fig. 4.29.), dung densities in winter indicated a weak positive trend" (R2=0.0114), while in summer there was a weak negative trend (R2=0.0641). When compared with sodium, dung densities showed a very weak positive trend (R2=0.0092) in winter and a negative trend in summer (R2=0.0834). In winter, when compared with dung densities potassium showed no trend (R2=0.001), but in summer, there was a weak negative trend (R2=0.0076). In winter, calcium does not show any relationship with dung densities (R2=0.0002), while in summer, there is a weak negative trend (R2= 0.0511). Magnesium content does not show any relationship with dung densities (Fig 4.33) in the winter season, (R2=0.0007), while in summer, there is a weak negative trend (R2=0.004). Zinc shows a weak positive trend (R2=0.0298) in winter and a weak negative trend (R2=0.026) in summer. Principal component analysis of nutritional parameters indicated nine components that were influencing dung density distribution in the study area in both the seasons, and hence no single parameter influenced elephant habitat use. The study clearly indicates that the distribution of elephants in Chilla Range of Rajaji National Park is more related to abundance of woody species and proximity of water, than the nutritional content in plant species. Principal component analysis showed that there was no single parameter that influenced dung distribution in the study area. This could be due to the fact that plant species selected for foraging by elephants contained an adequate amount of nutrients in most species for meeting foraging requirements .an d they probably meet their daily requirements by foraging on varied proportions of plant species.Item Winter Ecology of Three Species of Phylloscopus Warblers(Wildlife Institute of India, Dehradun, 2007) Ghosh, Mousumi; Singh, Pratap; Mohan, D.This study focused on three species of Phylloscopus warblers, P. humei, P. xanthoschistos, and P. chloronofus which overwinter sympatrically in the foothills of western Himalayas. The patterns of habitat occupancy, foraging behaviour, and foraging microhabitat of three species of warblers were examined to determine the nature of ecological complementarity facilitating their co-existence in the non-breeding season. Moreover, investigating the morphology-ecology associations among congeners also becomes critical since recent divergence may hinder our understanding of the mechanisms of their ecological segregation, as is the case with these species. Hence, morphology-ecology associations were also examined. A total of 91 points were sampled for bird detections five times each between December 2006 and March 2007. Prey abundances across habitat types were quantified. Behavioural data was also collected. The three species were found to differ in the occupancy of the sampled area. However, the bird occupancy did not correlate with differences in prey abundances across habitat types. The warbler species showed clear segregation in the use of foraging behaviour, foraging microhabitat, and proportion of large prey intake. The movement pattern was also found to vary across the three species. Morphology-ecology associations revealed the close interaction of morphology and ecology in shaping the ecological segregation of the three species in the non-breeding season. One major finding was that P. xanthoschistos is able to meet its demand for large arthropods in this northern site (31.5 % large prey intake) previously believed to be low in large arthropod abundance. Finally, the study demonstrated that the ecology of P. xanthoschistos (previously Seicercus) is very similar to other members of the genus Phylloscopus.Item Habitat use and food selection by wild and domestic ungulates in the Sikkim Transhimalaya.(Wildlife Institute of India, Dehradun, 2007) Chanchani, Pranav; Rawat, G.S.By defining a resource, determining the resources available to animals and sampling the array of resources actually used by an animal (Krebs 1999), it becomes possible to gauge the nature of interactions between species. This study explored aspects of resource use by diverse assemblage of wild and domestic herbivores including The Tibetan argali (Ovis ammon hodgsoni), Tibetan Gazelle (Procapra picticaudata), kiang (Equus kiang), blue sheep (Pseudois nayaur), domestic yak and sheep in a Trans-Himalayan environment during the lean winter period. Sampling was carried out in a systematic manner using trails, as well as by sampling opportunistically. To quantify vegetation, a 3.52 Ian grid was overlaid on an image of the study area, and grids were randomly picked from these for random sampling. A number of habitat and vegetation variables were measured or noted for all ungulate sightings or within vegetation sampling stations and these were used in analysis to ascertain patterns of habitat use and food selection. U sing a hierarchy of spatial scales, the study modeled animal distributions, and investigated the use of habitats and food habits of ungulates in relation to the availability of these resources in their environment. The study's major findings were that all ungulates were found to occur in the true Trans-Himalaya except for the blue sheep which selected more mountainous terrain in the transition zone between the greater and Trans-Himalaya .. Statistical tests of significance revealed that ungulates differed from one another or from random in their use of resources. Further, terrain features appeared to influence habitat selection to a greater-extent than vegetation. Finally, the findings of this research indicate that although the wild and domestic ungulates of this region all exist in relatively large numbers, they tend to vary in their use of habitats and food either by differences in their distribution, or in the selection of finer environmental (habitat and food) variables. The study therefore concludes that competitive inter-specific interactions are not very apparent in this region.Item Food habits of tiger (Panthera tigris tigris) in Sariska tiger reserve, Rajasthan(Wildlife Institute of India, Dehradun, 2003) Avinandan, D.; Sankar, K.; Qureshi, QamarThe present study aims at understanding relationship between tiger and its prey in a semi arid tract. The study was conducted in Sariska tiger reserve, Rajasthan over a period of six months from November 2002 to April 2003. Density estimation of major wild and domestic prey species was done to assess availability to tigers in terms of density and biomass. The line transect method was used to estimation prey densityItem Density Related Behaviour of Select Ungulate Species in Four Zoos of Southern India(Wildlife Institute of India, Dehradun, 2003) Panda, Prajna Paramita; Choudhury, B.C.Density Related Behaviour of Select Ungulate Species in Four Zoos of Southern IndiaItem Habitat Selection by Indian Peafowl (Pavo cristatus linn) in Gir forest, India(Wildlife Institute of India, Dehradun, 1993) Trivedi, Pranav; Johnsingh, A.J.T.A study on habitat selection by Indian peafowl (Pavo cristatus) was carried out in Gir National Park and Sanctuary over a period of five months. Open width line transects were laid at three study sites in West, Central and East Gir respectively to obtained information on availabili ty and use of habitats. Three hundred and thirty sightings were obtained in 90 transect walks (totalling to ca 113 km), of which two hundred and fifty occurred in West, and forty each in Central and East Gir. As sampling intensity was the highest in Sasan (West Gir), much of the analyses is based on the data collected here. Peafowl distribution was found to be clumped, with the degree and site of clumping being affected by water and food availabilityItem Habitat Use, Group Size and Activity Pattern of Goral (Nemorhaedus goral) in Simbalbara Sanctury (Himachal Pradesh) and Darpur Reserved Forest (Haryana) India(Wildlife Institute of India, Dehradun, 1993) Pendharkar, Anand; Goyal, S.P.A study on the habitat use, group size and activity patterns of goral (Nemorhaedus goral) was undertaken from November 1922 to May 1993 in Simbalbara Sanctuary (Himachal Pradesh) and Darpur Reserved Forest (Haryana). Data on availability of habitat types, vegetation types, slope, aspect and cover and their corresponding use (N=230 sightings), were collected along six search paths. Group size and activity pattern data were collected by walking along search paths and using instantaneous scan sampling. The broad habitat types identified were: Valley slope, Grassy slope, Ridge top flat, Nala slope, Valley bottom flat, Ridge top slope and Valley ridge slope. The vegetation types identified in the study area were: Sal forest (SF), mixed forest (MF), mixed forest grassy slope (MFGS), mixed forest riverine (MFR), sal forest riverine (SFR), pine-mixed woodland (PMW) and mixed forests with khai plantation (MFKP).The characteristic features of habitat and vegetation types and seasonal variations in them are discussed.The major findings of availability-utilization analysis were : Goral shewed preferential use of grassy slopes in summer. Valley bottom flat was used less in both the seasons. Mixed Forest was preferred in both seasons, whereas Mixed Forest Grassy Slopes were preferred only in summer. Sal Forest, Sal Forest Riverine and Mixed Forest with Khair Plantations were used less in both the seasons. A preferential use of the steep slopes was observed in winter. In summer there seemed to be no selection for terrain type. South facing slopes were preferred in both the seasons. Extremely low shrub cover and medium grass cover were selectively used by goral. Major features of goral group size and activity pattern were: Goral was predominantly a solitary species forming loose aggregations of upto eleven individuals. Average group size of goral did not vary significantly (N=230, d. f.=3, p=0.05, X" - 0.98) between seasons, but during late evening hours, comparatively larger groups were observed in winter (N=127, d.f.=4, p=<0.02, X2 - 12.42). Group sizes were comparatively larger in disturbed areas (N=230, d. f.=3, i i i p<0.01, = 12.75). A significant difference in proportion of time spent in different activities was observed (N=416, c/.f. = 8, p<0.001, X2 = 37.59), between winter and summer. Nevertheless, activities and proportions of active and inactive individuals varied significantly over different hours of the day (N=192, d.f.=2, p<0.01 , 10.43).Item Habitat Use by Goral (Nemorhaedus goral bedfordi) in Majhatal Harsang Wildlife Sanctuary Himachal Pradesh, India(Wildlife Institute of India, Dehradun, 1993) Mishra, Charudutt; Johnsingh, A.J.T.Studied the habitat use pattern of goral (Nemorhaedus goral bedfordi} in Majhatal Harsang Wildlife Sanctuary in the Himalaya to determine its habitat requirements. Of special interest were the roles of forage availability and quality and the antipredator strategy of goral in determining its habitat selection. These factors are of paramount importance in influencing the habitat selection by mountain ungulates. Diet composition of goral in terms of the proportions of graminoids versus browse was determined through pellet analysis. Its escape strategy was determined by direct observation. These results were then related to the actual habitat use patterns, which were determined by obtaining and quantifying locations of goral (n=334) over two seasons, along five monitoring trails. Use of each habitat category was interpreted with respect to its availability. A non-mapping technique was used for determining the availability of each habitat component. I identified nine vegetation types based on physiognomy and floristics. These were: Open Pine Community (OPC), Dense Pine Forest (DPF), Open Oak-Pine Community (OOPC), Dense Oak-Pine Forest (DOPF), Nullah Oak Forest with Low undergrowth (NOFL), Nullah Oak Forest with High undergrowth (NOFH), Euphorbia-Woodfordia-Dodoenia Scrub (EWDS), Open Euphorbia Scrub (OES) and Low Altitude Nullah Forest (LANF). Both forage quality and the antipredator strategy had a profound influence on habitat selection by goral. Goral was a grazer. It was partial to the younger, more nutritive grass phenophases - a prediction that can be made on the basis of its small body size. It preferred open areas with extensive grass cover. Forest cover, along with cliffs, was an important escape area for goral. But it avoided areas with extensive shrub cover. Such areas have little grass. Besides, the shrub cover obstructs visibility and quick movement, and makes the animal vulnerable to predation.Item Diurnal and Seasonal Activity Pattern of Water Monitor (Varanus salvator) in Bhitakanika Wildlife Sanctuary, India(Wildlife Institute of India, Dehradun, 1993) Pandav, Bivash; Choudhury, B.C.This study investigated the diurnal and seasonal activity pattern of water monitor, Varanus salvator in Bhitarkanika Wildlife Sanctuary, India. The study was conducted in an intensive study area of 17 sq.km selected after a pre sampling survey in the Sanctuary. The methodology involved to record the activity pattern of water monitor was monitoring of two permanent standard paths every three hours on diurnal basis. Sightings of water monitors were recorded while walking on the standard path. Behaviour of water monitor was divided into four categories such as basking, foraging, resting and non-foraging. Microhabitat of water monitor was recorded on each sighting. Ambient and substrate temperatures and ambient relative humidity were recorded along with diurnal activity pattern of water monitors. Results show a shift in diurnal activity pattern with season. The activity pattern of water monitor was unimodal in winter and uniform in summer. Basking was the major activity of water monitor in winter, whereas all the activities were evenly spread out in summer.The lizards used different microhabitats for different activities. Maximum lizards were recorded active at cooler substrate temperatures (29°C). The relation of ambient and substrate temperatures with activity was curvilinear. At low ambient temperature basking was prevalent. With increase in temperature other activities, such as foraging and resting were recorded. At high ambient temperature lizards selected cooler substrates. Ambient temperature and ambient relative humidity varied inversely. The activity was low at high levels of humidity It is concluded that behavioural thermoregulation plays a major role in water monitor’s activity.Item Factors Affecting Habitat Selection and Feeding Habits of Smooth Coated Otter (Lutra perspicillata) in Periyar Tiger Reserve, Kerala(Wildlife Institute of India, Dehradun, 2001) Anoop, K.R.; Hussain, S.A.Otters are the top predators of the aquatic ecosystems. Despite their important place in the food web and wide distribution, the knowledge on their ecology is relatively scanty as compared to other carnivores. sediments. nutrients, energy and biota, dams interrupt most of the ecological processes of the river. This includes changes in the fish communities because of changes in water current and depth. The aim of this study was to look at how otters adapted themselves for living in a man modified aquatic system. The factors affecting habitat selection and feeding habits of smooth-coated otter was studied in Periyar Tiger Reserve, Kerala during November 2000 to April 2001. The importance of different habitat parameters influencing habitat selection was assessed using ordination technique. The food habit was examined by analyzing the spraints (scats) using both frequency of occurrence and score-bulk estimate methods. The habitat of the animal was visualized as a multidimensional space in which the animal selected a few combinations of parameters./Foraging sites with high densities of fish, areas that offer den sites. The signs that the animal leaves on the banks while using an area were identified as -holts, communal spraint sites, grooming sites and footprints. Presence of these signs were considered as sure indicators of intensive use of an area by the otters. Subsequently, 96 random plots of 250 x 10m (2.5 km2 area) were placed along the banks 'of the reservoir and each plot was characterized by means of 17 habitat variables. Of these variables, three viz. water depth, distance to vegetation cover (escape cover) and numbers of streams joining the lake were outside of the plot. Each of such plots was accordingly assigned to the category of either used or unused by the animal based on the presence or absence of evidences in the plots.The complex data collected from the plots was reduced to three uncorrelated axes using Principal Components Analysis sacrificing 300/0 of the variability of the system the plots had a position, which characterized them in terms of variety and variability. Then each of the plots was marked as either used or unused based on the evidences found in the plot. It was found in the newly created three-dimensional space, the used and unused areas were segregated in distinct regions. The coordinates of the used plots indicated that the otters selected less rocky areas of the shallower parts of lake, which are narrower and slanting. The number of streams joining these areas was more than other stretches of the lake and the vegetation on the banks was dense. The otters did not use the deeper and wider areas of the lake. Other unused areas were steep and rocky parts of the reservoir where no streams joined. The higher fish congregation in the areas of mouths of streams must be the reason why otters' used those areas more in comparison to other areas. The low water depth made the dives of otters in these areas more effective while foraging. The thick vegetation cover of the banks provided them shelter and narrower areas helped them in patch fishing i.e. reducing the chance of fish to escape by forming an arch around the shoals of fish. Mann - Whitney 'U' Test, confirmed this observed pattern.Then a logistic regression model was developed using animal presence I absence as the dependent variable and the habitat variables as covariates. The model selected only rockiness and number of streams from the complex set of variables to predict the probabilities of otter presence in each of the 94 plots chosen for characterizing the otter habitats. Out of the 70 plots, which showed positive signs of otters, 95.71 % were classified in the region of higher probability of occurrence. But out of the 24 plots, which showed no signs of otter occurrence, only 54.17% were correctly classified in the region of lower probability of occurrence. This shows that some of the areas, which showed no signs of otter presence, were potential areas but at the time of this study they were not using these areas for unknown reasons. This may also be due to the inherent problems of using spraints and tracks to assess the degree of use of an area by otters. Feeding habits of otter were studied by analyzing 94 spraints collected from around the Periyar lake. Prey remains were identified using standard references prepared with identified body parts for 12 fish species that were collected during the study period. Two methods were used to estimate the proportions of different prey items consumed viz. frequency of occurrence method and score-bulk estimate method. The former method takes into account the presence or absence of prey items with no consideration of its quantity whereas the later includes the quantity of each of the prey item consumed, by including proportion of each prey item in the spraint and total weight of the spraint. It was observed that in the frequency of occurrence method the major prey items were under estimated and minor items were over estimated, as it did not take into consideration, the proportion of each item individual The number of prey items in a spraint varied between 1 and 7 in a single scat, the average in lower water levels in the reservoir (December, January and February) being 3.21 (varied between 1 and 5) and during higher water levels (March and April) it was 2.73 (varied between 1 and 7). Fish was the major prey item (96.02%), followed by frogs - --(l.08%), crabs (l.07%), birds (1.07%) and insects (0.76%). During the study period. remains of six fish species were found in the spraints.Among these, Tilapia (Oreochromis mossambicus) was the major prey of otter (51.54% of the total diet) followed by catfish (Heteropneustes tossilis), which formed 21.27 % of the diet, curmuca barb Gonoproktopetrus curmuca; 12.37%) and European carp (Cyprinus caprio; 9.16%). A linear relationship was stablished between the total length of the fish and the length of the vertebrae. For this purpose a total of 43 fish belonging to different size classes were used and 215 measurements of vertebrae were taken. From the scat of otters, vertebrae were sorted out and lengths of the corresponding fish were found out. Otters seemed to be consistently taking more fish of size 8.0 cm to 15.0 cm (29% each), followed by 5.0 cm to 8.0 cm class (23.70/0) and 14.0 to 17.0 cm class (14.4%). Attempt to quantify fish availability in the lake to determine the preference failed because of the hindrance caused by submerged tree stumps that damaged the fishing nets. From this study it was concluded that the otters in Periyar lake have adapted to a man modified condition utilizing most common exotic fish species of the lake and selecting those stretches of the lake where the physical constraints of diving did not interfere much with their foraging success. They were also tolerant to a great deal of anthropogenic disturbances such as presence of motorboats and humans. This shows the remarkable adaptability of the species. Furthermore 60 % of the diet was found to be comprised of exotic fish. Thus the changes in the natural habitat both in terms of food and shelter has been successfully compensated by adopting alternate means for survival. As the entire catchment of Mullayar and Periyar are well inside the park boundaries, the pollution and anthropogenic disturbances are minimum in the lake. This may be the reason why Periyar is still supporting a healthy population of otters even though they are getting exterminated from many of its former distribution ranges. So the otter population Periyar Tiger Reserve should be considered as a precious possession of the park.