M Sc Dissertation(WII)
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Item A Study of Vigilance Behaviour of Chital (Axis axis) in Pench Tiger Reserve, Madhya Pradesh(Wildlife Institute of India, Dehradun, 2009) Ghuman, Sartaj S.; Sankar, K.Predation is an important agent of natural selection in animal communities and so vigilance behaviour has very high selection pressure acting upon it. During feeding bouts, unless plant density and biomass are high and food intake is limited only by the processing rates, herbivores tend to experience a trade-off between vigilance and feeding. Thus, vigilance as a behaviour pattern ought to be tightly regulated by the cost-benefit ratios. A study on vigilance behaviour of chital (Axis axis) was conducted at Pench Tiger Reserve, Madhya Pradesh from December 2008 to April 2009. The objectives of the study were to examine the determinants of individual and group vigilance in chital; and also to examine the t effect of conspecific behaviour on individual vigilance. I used scan sampling with fixed interval recording to estimate group vigilance and focal animal sampling with continuous recording to estimate individual vigilance levels. Three main factors that are known to affect :, vigilance from studies on other herbivores were examined: group size, density of animals in the group and visibility. Scanning behaviour was used as an estimate of vigilance. 'Scanning' refers to the state when the animal has its head above shoulder level and the senses of sight, smell and hearing are actively 'scanning' the environment. Individual vigilance was found to decrease with increasing group size, decreasing density and increasing visibility. In large groups adult males, fawns and adult females with fawns were found to be significantly more vigilant than females without fawns and yearling males. Group vigilance level was found to increase significantly with increasing group size, even as the group scan level decreased. Individuals seemed to reduce vigilance with relation to group size rather than the group vigilance level. The results suggest that individual chital do not adopt levels of scanning that maximize cooperative predator detection. The benefits of the group size effect vary with age-sex classes and other probable internal and external predation risk Factors and so vigilance is more likely governed by a combination of dilution and detection hypotheses mechanisms, the focus changing from one to the other with individual risk.Item Space Use Patterns of the Indian Giant Squirrel (Ratufa indica centralis Erxleben) in Relation to Food Availability in Bori Wildlife Sanctuary, M.P. India(Wildlife Institute of India, Dehradun, 1993) Datta, Aparajita; Goyal, S.P.The spatio-temporal heterogeneity of food supply and the consequent effects on food resource use and space-use patterns of the Indian giant squirrel (Ratufa indica centralis) in Bori Wildlife Sanctuary, was the focus of study. Territoriality, which may affect space-use patterns of individuals was of special interest. Climatic factors which may influence activity budgets and consequently the variability in seasonal space-use patterns are also discussed. Based on individual variation in physical characteristics, Z identified three focal animals (one male, one female and a subadult male) in the disturbed habitat (Bhainsa nala ) , and a male and female in the undisturbed habitat (Churnagundi nala) for whom dana could only be gathered in winter. Therefore seasonal changes in space-use patterns is discussed for focal squirrels in the disturbed habitat. I kept a continuous record of behaviours during focal animal sampling. Home areas were calculated based on hourly locations taken from focal data. I gridded the area used by focal squirrels and recorded the vegetation parameters. The seasonal change in resource availability was monitored by phonological observations on all trees in the grids twice a month. Squirrels in Bhainsa nala selectively utilised certain individuals of flowering and fruiting crees which was related to crop size. Squirrels included bark and leaves in their diet even when fruit resources were available. The resource use by squirrels in Churnagundi nala showed a marked difference from squirrels in Bhainsa nala in winter which was due to the poor availability of food. Individual squirrels in Bhainsa nala showed variation in food species, food items used and the percent time spent feeding on each food item indicating that resource availability was not the same for all squirrels. No significant correlation was found between resource abundance and percent use of the item. Squirrels had overlapping ranges but were otherwise solitary. Many preferred resources were rare in the habitat, and the spatio-temporal heterogeneity in food resources resulted in overlap between individuals at locally abundant food resources. Because of this heterogeneity, the defence of an exclusive area guaranteed of resources throughout the seasons is not possible. Therefore squirrel ranges overlapped, but encounters were avoided by spatial time sharing but when encounters occurred, overt aggression was seen. But at certain locally abundant resources which were located at the periphery of the home areas, squirrels tolerated each other by maintaining inter-individual distances (5-10m). The tolerance of conspecifics at these resources could also be related to the existence of dominance hierarchies which result in decreased over aggression. The intensity of use (time spent) decreased as the distance from nest increased for all squirrels. Squirrels made forays in search of food and in many cases foraging was in the peripheral areas of the range. The male’s range showed overlap with the female’s in winter which could be related to sexual activity. Squirrels had a bimodal activity pattern in both seasons but bimodality was less pronounced in the winter since activity was distributed throughout the day when temperatures were more equable Shift in onset and cessation of activity was observed with changing daylength. Time spent feeding in April was much less than in other months. Time budgets showed that in all months a higher proportion of time is spent resting which could be due to heat or cold stress in or time needed to digest food items eaten. in Activity pattern of the squirrels in winter in Churnagundir nala were influenced by the low resource availability which resulted in long basking and resting periods and negligible time spent in feeding. Though occasional forays of short duration were made, no food was located by these forays. Thus squirrels adopted a strategy of conserving energy by minimizing their requirements by resting.Item Avian Communities in the Riparian Areas of Bori Wildlife Sanctuary, India(Wildlife Institute of India, Dehradun, 1993) Pai, Ashwini; Johnsingh, A.J.T.Riparian areas are important as special habitats and corridors for wildlife. However, in India, riparian areas have not been studied to any detail. Also, not much is known about the avifauna of riparian habitats. The vegetation near a riparian area tends to be dense and hence distinct owing to constant availability of water. Riparian areas come under heavy use, both by livestock as well as wild animals because of the presence of water and forage. The avifauna of riparian areas is rich due to its floral complexity and structure and resources like fish and insects. This study quantified bird species diversity, avian guilds and avian community structure found in four riparian areas ( a flood plain, a riparian scrub, a disturbed nulla and an undisturbed nulla) of Bori sanctuary in Central India. The riparian areas were compared with the adjoining deciduous forest for avifaunal differences. Vegetation was studies along the riparian areas and the deciduous forests, using circular plots. Tree and shrub densities, vertical stratification of foliage and species richness were quantified. Line transects were used to estimate bird ,species richness and abundance. Bird species richness was correlated to negative variables for the two seasons. In summer the BSR was highly correlated with CC and in winters with CC. Stepwise multiple regression was used to create a habitat model for BSR in summer and in winter. Community patterns show seasonal change and also respond to structural changes of habitat.Item Habitat Occupancy by tiger Prey Species Across Anthropogenic Disturbance Regimes in Panna National Park, M.P.(Wildlife Institute of India, Dehradun, 1999) Mathai, Manu Verghese; Chundawat, R.S; Qureshi, QamarEffect of anthropogenic disturbance on habitat occupancy by tiger prey species was studied in Panna National Park, Madhya Pradesh. The study was conducted between November 1998 and April 1999. Line transect method and Pellet count technique were used to estimate abundance for all ungulates. Abundance estimates were used as a measure for intensity of habitat use by all species. The density estimates from line transects are associated with high coefficient of variation, which is largely a function of the small sample size resulting form extremely low densities. Ordination of habitat parameters grouped the transects based on habitat quality and structure, disturbance and topography. Anthropogenic disturbance was found to be an important factor, influencing habitat quality and differential use of habitats by animals. Sambar associated strongly with low disturbance hill habitats and poorly with relocated village sites and disturbed plateau transects. Indications from line transects and pellet count method concur in the case of sambar. Chital were very localised in their distribution being strongly restricted to secondary successional stages and ecotones between relocated village sites and woodland. Nilgai was a generalist in terms of habitat occupancy. In case of nilgai the two methods complement each other with the information they provide. The information from pellet-group counts was found to reflecting patterns that are not detected by direct sampling methods like line transects. Chinkara was strongly associated with the disturbed areas, largely because of its openness, but also found in the undisturbed areas. Wild pig, like nilgai, was a generalist, but showed preference for fringe areas of forest adjoining agricultural fields. Langur showed a marked preference for hill habitats and did not differentiate between disturbed and undisturbed hill habitats. Langur also showed the strongest association with water. The distribution of preferred prey, sambar and chital is localized. Nilgai, which is distributed throughout the study area, is found in habitats not favorable for tigers. Such a distribution would probably only support dispersing and transient animals. Therefore habitat management should be aimed at maintaining and expanding habitats suitable for cervids. Disturbance in the form of livestock grazing and woodcutting are largely responsible for maintaining poor habitat quality. The cause for these disturbances cannot be disconnected from the socio-economic and cultural reality of the people, both near and far, and therefore the conservation of the tiger has to address these aspects rather than restricting only to the biology of the animal.