Theses and Dissertations
Permanent URI for this communityhttp://192.168.202.180:4000/handle/123456789/1
Browse
3 results
Search Results
Item Impact of land use changes on the habitat, bahaviour and breeding biology of Indian Sarus Crane (Grus antigone antigone) in the semi-arid tract of Rajasthan, India.(Wildlife Institute of India, Dehradun, 2007) Kaur, Jatinder; Choudhury, B.C.The Sarus Crane has been recorded all over the northern India and central region of the Indian sub-continent historically. However, this once abundant tallest flying bird species has now become threatened. The present study was undertaken during the year 2000-2002 to i) to determine the habitat use, breeding biology and behavioural ecology of the Sarus Crane in the semi-arid tract of Kota, and Bharatpur in Rajasthan, and ii) to determine the changes in land-use and its impact on Sarus Crane in the semi-arid landscape and to suggest the conservation strategies for the long-term survival of Sarus Crane. The study was conducted in the semi arid tract of Kota, and Bharatpur districts of Rajasthan. District Kota, the first intensive site falls under arid Zone V (the humid south-eastern humid plain zone,) where the development of canal irrigation has made this area rich in agricultural production. The population of Sarus Crane in Kota are dependent mainly on the canal system induced and other natural wetlands. Data on distribution and habitat utilization of Sarus Crane in Kota and in Keoladeo Ghana National Park were carried outItem Behavioural ecology of sloth bear in Panna National Park, Central India.(Wildlife Institute of India, 2005) Yoganand, K.; Johnsingh, A.J.T.The patterns in daily and seasonal activity of sloth bears in Panna NP were studied and the factors that influenced the patterns were assessed. • Activity states were recorded by manually monitoring radio-tagged, motion-sensor fitted bears, and by deploying automated receiver-recording units that logged the strengths and pulse rates of signals from the bears. Daily and seasonal changes in temperature, relative humidity and other heat indices of the microhabitats used by bears were recorded using temperature and RH loggers. Tiger and human activities were also monitored to assess the influence of these on bear activity patterns. • Bears were found to be essentially nocturnal and crepuscular in activity and they rested during midday. This pattern of activity was similar among all radio collared bears, but with some variability. The differences in diel activity patterns among climatic and fruiting seasons were rather small. In the wet and cold seasons, bears extended their activity into the day hours and reduced their activity in post-midnight, pre-morning hours, as compared to the dry season. • Bears (except the cubbing females) were active almost every day of the year, and for several hours (> 10 hours) each day. Overall, bears were active for 48% to 54% of the whole day (out of 24 h) in all seasons. There were no large differences seen among months in percent of whole day, day time, night time, and morning time the bears were active, but evening time showed large differences. • The differences in activity start and end times among individual bears within seasons were large in certain seasons, and the differences among seasons of a bear were large for certain bears. Bears such as F63, F78 and M69 did not show much difference among seasons, while others such as F76, F80 and M50 showed large differences. Also many bears showed higher variability in cold and wet seasons than in dry season, particularly in activity start times. • Bears started their activity later and ended it earlier in the dry season than the other two climatic seasons. The earliest activity start and latest activity end was in the cold season. The differences among climatic seasons in both timings were statistically significant (ANOVA, α = 0.05). However, when activity start and end times were adjusted for seasonal sunset and sunrise times, the patterns in seasonal differences changed remarkably. 109 Wet season activity start times with reference to sunset were much earlier than the other two seasons, whereas the difference between cold and dry seasons became small. Differences in activity end times after sunrise between cold and the other two seasons too became small. • Escarpment habitat was most frequently used (50% to 85%) for day resting by bears in all months, followed by Lantana shrub thickets (15% to 50%). The use of escarpment was predominant in dry season months and decreased in monsoon and post-monsoon months, with a converse increase in the use of Lantana habitat as day-bed. • The core bears, which had substantial escarpment habitat available within their home ranges, used escarpments for day-resting predominantly in all seasons, and the peripheral bears, which had low escarpment and high Lantana cover available, used these habitats for day-resting variably. Tigers were generally nocturnal and crepuscular in activity during the dry and cold seasons. The activity of tigers peaked during crepuscular times; they predominantly rested during mid-day, and had a reduced level of activity during post-midnight, pre-morning hours. • Diel activity patterns of bears and tigers were similar to a large extent, in the two seasons tigers were monitored. The activity peaks of both species more or less coincided in the mornings and evenings, and high levels of activity of both occurred in night and crepuscular times. • Tiger activity does not seem to influence bear activity timings. The hourly activities of both were strongly positively correlated, even after controlling for temperature, with which bear activity was strongly correlated. • Humans using the forest habitats showed a high level of activity in the morning and evening times, moderate level of activity in the mid-day, early morning and late-evenings, and a low level of activity in the immediate premorning and early night hours. • Human activity overlapped highly with that of bear activity during early morning and evening hours. Overlap period was longer and the activity peaks of both coincided in the evenings of wet and cold seasons. No relationship could be seen between their hourly activitiesItem Behavioural Ecology of Colony Formation and Function of Colonial Breeding in Chtnut-Headed Bee-Eater.(Wildlife Institute of India, Dehradun, 2011) Supriya; Vasudevan, K.; Mohan, D.Breeding in densely distributed territories that contain no other resources apart from breeding site is known as colonial breeding. Despite several long-term investigations, there are several questions regarding colony formation, the function of coloniality and the variation in colony sizes that remain unanswered. Chestnut-headed bee-eaters (Merops leschenaulti) are tropical Old World birds (Family Meropidae) that breed both solitarily and in small colonies. Hence they are well-suited subjects for the study of colonial breeding. This study was conducted for five months from December 2010 to May 2011 in parts of Haliyal division and Karwar division in Uttara Kannada district, Karnataka. It is an attempt to explain the variation in colony size through gaining insights into the behaviour of colony formation and function of colonial breeding. A combination of measuring habitat characteristics, capturing and measuring birds, recording reproductive success of breeding pairs across a gradient of colony sizes and behavioural observations were used. A total of 17 nests were found during the course of the study distributed over three colonies and five solitary nests. No significant difference was found between habitat characteristics at solitary and colony nests. Also, there was no shortage of potential breeding sites, as found by the ratio of number of nests to the amount of substrate available. This suggests that the mechanism of colony formation in CHB is conspecific attraction and is not merely habitat mediated aggregation. The body size of the colony nesters was found to be greater than the body size of solitary nesters. This implies that the optimum colony-size is different for different individuals, with larger individuals having a preference for colony nesting. Program MARK was used to analyze nest survival data. It was found that the daily survival rate of nests was not significantly different across colonies of different sizes, lending further credence to the hypothesis that different individuals have different colony-size optima. Colony nests were initiated about a week before the solitary nests and nesting was more synchronous at colony sites. During the nest digging stage of breeding, a number of aerial chases were observed between the birds, which hint at a role for despotism in influencing variation in colony sizes. Provisioning frequency was found to be higher and showing larger variation at solitary nests than at colony nests. A possible explanation for this is that there is greater competition at colony sites. Therefore, colony-nesting must be having some other benefit that compensates for the cost of competition. Further investigations into the conspecific cue that mediates colony formation and· the benefit of coloniality need to be carried out.