M Sc Dissertation(WII)

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Tadpoles with a Trick : Overwintering Ecology of Tadpoles in a Himalayan Stream, Uttarakhand India
(Wildlife Institute of India, Dehradun, 2021) Jithin, V.; Das, Abhijit; Johnson, J.A.
Overwintering is a unique phenomenon of delaying metamorphosis in amphibian larvae at low temperature conditions prevailing at high elevation and latitude. This study is first of its kind in India to look at selected ecological aspects of overwintering tadpoles of Nanorana spp. in a Himalayan stream
Assessing the Impact of Traditional Practice of Frog Consumption Amphibian Population from Mizoram India Culture -Nat
(Wildlife Institute of India, Dehradun, 2021) Malsawmdawngliana; Das, Abhijit; Kawlni, Lallianpuii; Lalronunga, Samuel
Cultural practices have shaped the natural resources around the area in all parts of the world. The traditional practices involving wildlife and their meat as food resources is widely practised by many tribes of the world. Such practice also involves amphibian exploitation as food, one of the critical reasons for the decline in the global amphibian population. Such practice is widespread in the Northeast part of India, including Mizoram. However, the population-level impact of such traditional practice is poorly known. The study was carried out in the buffer and core zone of Dampa Tiger Reserve (DTR) to assess the abundance and species richness. We surveyed four villages around DTR to see how the pattern of frog consumption by the local communities. The study tried to understand how the species diversity and abundance is affected by the off-take of frogs for food in the study area. Time constrained nocturnal Visual Encounter Survey method was used to see the species composition and abundances in the study area. Random sampling using questionnaires and interactions were used to see the frogs’ consumption pattern, medicinal use and preferred species for food of the local communities in the study area.
Thermal Ecology of Spiny-tailed lizard and its vulnerability to climate warming.
(Wildlife Institute of India, Dehradun, 2021) Tatu, Avichal; Dutta, Sutirtha; Das, Abhijit
Lizards and other ectotherms survive within their thermal limits and have a well-defined range of body temperatures within which their performance is optimal. Hence, as climate warming accelerates, ectotherms like lizards become increasingly constrained. Saara hardwickii survives in areas where environmental temperatures are already extreme. Therefore, they may be at the risk of extinction due to rising temperatures. In the field, we collected data on field body temperatures and operative temperatures to evaluate and quantify the degree of thermoregulation observed in the lizard and to evaluate changes in activity pattern over months, In the laboratory, we quantified preferred temperature, thermal thresholds and locomotor of the lizard. Using a combination of field and laboratory data, we described how S. hardwickii uses burrows to thermoregulate and evaluated how climate warming will impact locomotor performance and hours of activity in the future. We found that burrows provide an exceptional buffer to the lizards as the temperatures deep inside (~1 m) do not exceed the preferred temperature of the lizard, even in the worst-case climate change scenario (RCP 8.5). Currently, the lizards are restricted to their burrows for six hours during their active period. According to our model, by 2100, the lizards might get restricted to their burrows for 7 hours in the best-case scenario, and for 9 hours in worst-case scenario. Our model suggested decrease in locomotor performance by 2.1%, 9.5% and 28.3% in the best- (RCP 2.6), intermediate- (RCP 4.5), and worst- (RCP 8.5) case scenarios by 2100. Hence, the synergistic effect of loss of activity hours and decline in locomotor performance might result in decreased fitness of S. hardwickii, potentially leading to its extirpation.
Montane Lizard in a Mosaic Landscape: Effect of Tea Plantations on Anamalai Spiny Lizard (Sales anamallayana)
(Wildlife Institute of India, Dehradun, 2021) Devrajan, Anjitha; Ramesh, C.; Das, Abhijit
The Anamalai Spiny Lizard (Salea anamallayana), an agamid lizard endemic to southern Western Ghats is reported to use shola and tea plantations of Kannan Devan hills of high ranges of Kerala. The Western Ghats has experienced extensive habitat destruction and modification since a very long time and the lizards are highly affected by habitat modification which in turn affect their fitness and survival. In this study we investigated the effect of habitat modification on morphology, population and habitat association in Salea anamallayana in the shola forests of Eravikulam National Park and surrounding tea plantations. The study was conducted from February 2021 to May 2021. Line transect method was used to study density and Visual encounter surveys for collecting data for basking habitat use and morphology. Surveys were conducted from 9 am to 2 pm since the lizard was more active during the time period. Shola and plantation are structurally very different. Shola was divided into shola close to plantations and shola away from plantation. Plantation was classified according to the proximity to shola and presence of shade trees. The density was found to be more in shola (27.59±6.79/ha) compared to plantation (8.63 ±2.21/ha). In plantations, the density was influenced by proximity to shola and presence of shade trees. Density is more in plantations in close proximity to shola (20.91±4.51/ha) compared to plantations away from shola (2.85±1.37/ha) and the lizard was present only where the shade trees were planted. The sex ratio was biased towards male in plantations (100:14) and it improves in shola close to plantations (100:33) and further improves in shola away from plantations (100:50). The body condition of male lizards was poor in plantations compared to shola away from plantations (t = 2.57, df = 14.17, p-value = 0.021). The males do not differ in other morphological variables across the habitats. Body condition of males is better than females (t = -2.19, df = 23.80, p-value = 0.037). The basking habitat use is in proportion to habitat availability. The microhabitat use varies across shola and plantation. Average perch height and perch diameter is more in plantation and average canopy cover is more in shola. More diverse perch surface is available and used in shola compared to plantation. The average body temperature is high in plantation compared to shola and the body temperature is directly proportional to atmospheric temperature and substrate temperature. There is no significant difference in Flight Initiation Distance (FID) between shola and plantation. FID is inversely correlated to substrate temperature.

M Sc Dissertation(WII)

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