M Sc Dissertation(WII)

Permanent URI for this collectionhttp://192.168.202.180:4000/handle/123456789/3

Browse

Author: search.filters.author.Chellam, Ravi

Search Results

Now showing 1 - 5 of 5
  • No Thumbnail Available
    Item
    Floristic Composition and Patterns of Regeneration of Rainforest Trees in the Fragmented Forests of the Anamalai Hills, Southern Western Ghats
    (Wildlife Institute of India, Dehradun, 2003) Balasubramaniam, Priya; Qureshi, Qamar; Chellam, Ravi
    The word diverse is almost a synonym for tropical rainforests. In no other habitat are found such an enormous number of life forms. These highly diverse systems are now facing severe threats as a result of habitat fragmentation. The aim of this study was to study the floristic composition and patterns of regeneration in the fragmented forests of the Anamalai hills, southern Western Ghats.Six fragments were chosen which varied in size and disturbance levels. They were- Iyerpadi (>2600ha), Andiparai (>185ha), Puduthotam (92ha), Pannimedu (66ha), Varattuparai 1c (11ha) and Varattuparai 4 (4ha). Quadrats of · 3 sizes were used to sample for different variables. 20 x 20m quadrats were used to enumerate tree sp, 5 x 5m quadrats were used to enumerate sapling sp and 1 x 1 m quadrats were used to count the numbers of seedlings. Height (m), GBH (cm), lopping I cutting signs, altitude, canopy cover, presence of weedy shrubs and ground cover of weedy herbs were the other variables measured. A total of 112 quadrats were laid, 25 in the first 4 fragments, 9 and 3 in the last two respectively. The findings revealed that tree and sapling generic richness showed a negative relationship with disturbance and time since isolation. Their correlations with area though positive were weak. Fragments were subjected to varied nature and levels of disturbance. Fragment characteristics such as area, time since isolation did influence the patterns of tree and sapling composition though weakly. There is an extremely weak correspondence between the tree and sapling composition of each fragment. There was a high number ' of non rainforest species in fragments which were relatively more disturbed. Relatively undisturbed fragments were more rich in rainforest trees · and saplings. Fragments showing higher levels of canopy openness were relatively more disturbed than others. Disturbed fragments also showed higher levels of weed invasion. Iyerpadi showed the highest generic richness in trees and saplings. Varattuparai 4 showed the least richness in both trees and sapling. Human disturbance due to its chronic. nature was the principal predictor of both tree and sapling composition.
  • No Thumbnail Available
    Item
    Impacts of Habitat Conversion on the Leaf Litter Anuran Community of Varagaliar, Western Ghats
    (Wildlife Institute of India, Dehradun, 1995) Saravanakumar, S.U.; Chellam, Ravi
  • No Thumbnail Available
    Item
    Ranging, Activity Patterns and Habitat Use of Blackbuck and Nilgai in Velavadar National Park, Gujarat, India
    (Wildlife Institute of India, Dehradun, 2001) Sahabandhu, H. Dhanushki R.; Chellam, Ravi; Mathur, V.B.
    I studied the activity patterns, ranging and habitat use of blackbuck (Antelope cervicapra rajputanae) and nilgai (Boselaphus tragocamelus) in Velavadar National Park from November 2000 to April 2001. Scan sampling was used to record blackbuck and nilgai activity patterns. Herds were also followed from sunrise to sunset to study the diurnal movements. Satellite imagery was used for vegetation mapping. Habitat availability and usage of both species were examined by plotting the grazing circuit on the satellite imagery. Activity patterns were found to differ amongst the various social groups, habitats and seasons. Temporal variations in foraging time and resting time were found in all the groups studied. Blackbuck had three foraging peaks and two resting peaks as compared to nilgai, which had two, and one peaks respectively. Diurnal distances were not found to differ in any of the different blackbuck or nilgai groups or between the two species. Differences between blackbuck herds in different seasons and habitats were attributed to the nutritional levels and the spatial dispersion of vegetation. Foraging behaviour decreased in summer supporting results of previous studies that blackbuck reduced foraging due to lower nutrition levels. Male blackbuck was found to forage 67% compared to 58% by females. This difference was attributed to larger body size in males, and the upcoming rutting/lekking season. No difference was found between nilgai males and females, except usage by females was slightly more in high nutritional areas. Female nilgai were found to become more selective in summer, by increasing their foraging time from 43% to 55%. But no difference in habitat usage was found, possibly due to sustenance from Prosopis juliflora pods. Blackbuck were found to spend more time foraging (53%) compared to nilgai (43%). This was due to blackbuck being more selective in the prevailing drought conditions, while nilgai were possibly supplementing their diet with P Juliflora pods. Differences between the two species in temporal allocation of foraging time was found which was ascribed to difference in gut capacity. No seasonal differences were found between the two species, except that nilgai were found to be using high nutrition areas. Nilgai were found to be more selective nutritionally than blackbuck, possibly due to nilgai being an intermediate feeder compared to blackbuck, which are coarse bulk feeders.
  • No Thumbnail Available
    Item
    Fruit Removal, Seed Dispersal and Demography of Emblica officinalis at Rajaji National Park, Uttaranchal
    (Wildlife Institute of India, Dehradun, 2001) Prasad, Soumya; Chellam, Ravi; Krishnamurthy, Jagdish
    Plant-frugivore interactions determine the structure and composition of plant and frugivore communities and consequently the understanding of these interactions may help in defining the management protocol for the conservation of these systems (Howe 1993). E.officinalis fruit are an important non-timber forest produce from Indian deciduous forests. In this study I have looked at fruit removal and seed dispersal patterns of E. officinalis in the context of its use by humans. Fruit removal patterns were followed for 19 E. officinalis trees with a range of fruit crops (from 73 ± 59 X 103 fruit to less than 100 fruit) at Dhaulkand, Rajaji NP. 11 of these trees were monitored to ensure that there was no human removal of the fruit. For each tree, all fruit on the ground in the fruit fall area and all fruit on 5 -7 marked branches were counted thrice every ten days in 12-hour intervals, till less than 5% of the initial number of fruits remained on the .marked branches, to arrive at nocturnal and diurnal removal patterns for fruit. Factors affecting fruit persistence (number of days fruit persisted. on the marked branches) were extraction of fruit by people and fruit crop size. In the fruit-fall area, factors affecting nocturnal and diurnal fruit removal rates were clustering of fruiting trees and human induced factors. A range of direct and indirect methods - tree watches, track plots and camera trapping were used to determine the identity of the fruit removers and to observe the mode of fruit handling by these removers. Langur (Semnopithecus entellus), ungulates such as chital (Axis axis) and barking deer (Muntiacus muntjac) were observed feeding on E. officinalis fruit. There was also evidence that the gerbil, Tatera indica, scatter hoards the fruit. Retention In ungulate rumens reduced germination success of E. officinalis seeds. Demography of E. officinalis and regeneration status of woody plant species at Rajaji was assessed along 6 one Ian transects' across a gradient of human use intensity, 3 each in hill and plain mixed forests. The E. officinalis population at Rajaji was found to have very few trees below 30 cm GBH. E. officinalis seedlings were found only in areas almost completely free from human use. Regeneration for tree species at Rajaji was dominated by species that are not lopped for fodder.
  • No Thumbnail Available
    Item
    Environmental Influences on Space Utilisation and the Activity Budget of Captive Leopards (Panthera pardus fusca) in Five Zoos in Southern India
    (Wildlife Institute of India, Dehradun, 1999) Mallapur, Avanti; Chellam, Ravi; Qureshi, Qamar
    A behavioural study was conducted on leopards in five zoos situated in Thiruvananthapuram, Chennai, Mysore and Bangalore between November 1998 and March 1999. Twenty six leopards were studied in five zoos of which sixteen were singly housed and ten were housed in groups. There were 16 males and 10 females. Only three of the 26 animals were captive born, 10 were captive reared and 13 were wild caught. Fourteen singly housed leopards were studied in on-exhibit and off exhibit enclosures on days with visitor presence and also on zoo holidays, two singly housed leopards were studied in the off-exhibit enclosures only. The group of ten at Bannerghatta Zoological Gardens, Bangalore was studied only in the on exhibit enclosure. Scan sampling method was used to record the behavioural patterns in leopards. The ethogram, which consists of all behaviour observed in five zoos lists 12 behavioural states and 29 behavioural events. The leopard enclosures were divided into imaginary blocks and the utilisation of these grids by the leopard was recorded alongwith behaviour at five-minute intervals. . Each leopard was studied for two days on-exhibit. two days off-exhibit and one zoo holiday. The leopard at Childrens' Park. Guindy was also studied for two excess visitor days during the Pongal festival. Information on each leopard was obtained from zoo records. No significant difference in behaviour was observed between males and females. and wild caught and captive-reared individuals. The behavioural repertoire of female leopards was significantly associated with their period of anoestrus. Stereotypic pacing was found to increase with enclosure size. Leopards housed in larger enclosures exhibited higher levels of activity and stereotypy behaviour. Smaller enclosures housed leopards that rested for longer proportions of time. Activity and resting behaviour peaks in the daily activity budget of the leopards were due to their crepuscular nature. The peaks in stereotypic behaviour in the daily activity budget were influenced by zookeepers' presence. Food-anticipatory behaviour was observed in all leopards before and during feed time. Individuals that were studied on-exhibit and off-exhibit exhibited higher levels of stereotypic behaviour off-exhibit and higher levels of activity behaviour on-exhibit. The presence of visitors also influences the behaviour repertoire of captive leopards. All singly housed leopards studied on days with visitor presence and zoo holidays exhibited higher levels of activity on zoo holidays and higher levels of resting behaviour on days with the presence of visitors. Six individuals were studied singly and then as pairs. The proportion of activity and resting behaviour exhibited when they were housed in pairs was higher and stereotypic behaviour, though not statistically significant, was lower than when they were singly housed. The utilisation of space differed between singly and group-housed leopards. Singly housed individuals utilised the "edge" and "back" zones of their enclosures more and the sructurally "enrich" zone less than group-housed leopards. Most of the leopards utilised the "edges" of their enclosure for stereotyping. the "back" zone for resting and the "rest" of the enclosure for activity behaviour. The structural features found within the enclosures that housed leopards were of two categories; sleeping platforms. trees and sheds that stimulated resting behaviour and logs. snags and tree trunks that stimulated activity behaviour. In enclosures that were structurally enriched with sleeping platforms, sheds or trees, leopards utilised the "enrich" zone of the enclosure for resting instead of the "back" zone. Enclosures having logs and snags. the "enrich" zones is utilised to exhibit activity behaviour. The utilisation of the structurally enriched zones of the enclosures was positively correlated with enclosure complexity. Leopards in structurally enriched enclosures exhibited higher levels of activity and lower levels of resting than the barren enclosures The factors that were found to influence the behavioural repertoire of captive leopards have been taken into consideration while recommending environmental enrichment techniques for the renovations of old enclosures and the construction of new ones.