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Author: search.filters.author.Panagoda, P.A.B.G.Subject: search.filters.subject.conservation

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    A census of diurnal primates in the villages located between Labugama-Kalatuwawa and Indikada forest reserves in Colombo District of Sri Lanka.
    (International Research Symposium on Pure and Applied Sciences, 2017 Faculty of Science, University of Kelaniya, Sri Lanka., 2017) Panagoda, P.A.B.G.; Weerasinghe, V.P.A.
    The diurnal primate populations which inhabit the villages, located between Labugama-Kalatuwawa and Indikada Forest Reserves in Colombo District of Sri Lanka, has a high conservation value due to the presence of critically endangered Semnophithecus vetulus nestor (Western purple-faced langur). In addition, these diurnal primate populations consisting of S. vetulus nestor and Macaca sinica (Toque macaque have caused many human-monkey conflict incidents within the area. No studies have assessed the local populations of diurnal primates within this area in spite of its importance in both above perspectives: conservation and conflict. Therefore, this study was aimed to assess the relative density and group size of diurnal primates and to statistically compare above two estimations between the two primate species. The census was carried out within a selected stripe of villages located between the two forests. Using reconnaissance walks, five trails (2 km each) were established to represent the study area, with a systematic sampling design. The trails were walked simultaneously, by five independent trained teams each consisting of five persons, in the morning and afternoon on 3rd of December, 2016. In addition, group counts of monkeys were made during 10 opportunistic field visits, from April to December 2016. For each species, the average group size and group and individual encounter rates (as a measure of relative density) were calculated. The group sizes and encounter rates of the two species were then statistically compared using Mann-Whitney U test. Group size of S. vetulus nestor (mean ± SE) was lower (4.46 ± 0.40 individuals) than that of M. sinica (8.29 ± 2.19 individuals), even though the median group sizes of the two species were not significantly different (p=0.1893). On the other hand, S. vetulus nestor was found to be more abundant in the area compared to M. sinica. The number of encounters of S. vetulus nestor and M. sinica during the census was 10 and 4 respectively. Further, the average group encounter rates (mean ± SE) of S. vetulus nestor and M. sinica, were 0.95 ± 0.31 and 0.33 ± 0.23 respectively (no. of groups/km) whereas the average individual encounter rates (mean ± SE) of S. vetulus nestor and M. sinica, were 4.23 ± 1.38 and 2.71 ± 1.89 (no. of individuals/km) respectively. However, no significant difference was found between the median group (p=0.470) and individual (p=0.4647) encounter rates of the two species. Yet, the higher abundance of S. vetulus nestor over M. sinica, could also be observed during the opportunistic observations made throughout the whole study period (opportunistic group encounters; 22 for S. vetulus nestor and 9 for M. sinica). The reliability of the results can further be improved by censusing at different times of the year. As this study sets a baseline, future studies are recommended to identify any growth or decline of this crucial population of primates.
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    Are human-modified land-uses important for avifaunal conservation or not? An example from Karanketiya, Rakwana, Sri Lanka
    (Department of Zoology and Environmental Management, University of Kelaniya, Sri Lanka, 2017) Weerasinghe, H.W.G.A.S.; Panagoda, P.A.B.G.; Panagoda, P.A.S.U.
    Improving conservation value of human-altered landscapes would be of massive importance, in years to come. The present study intended to assess the contribution of such landscapes in aid of conservation of avifauna. Abundance, species richness, species heterogeneity, evenness and composition of bird communities were analyzed on line transects during three months, including the migratory season, in three different land-use types namely, proposed reserved forest, tea estate and home gardens in Karanketiya, Rakwana. Total of 87 bird species including 79 residents with 15 endemics and 8 migrants were recorded. Species richness and total abundance per transect of three types of land-uses are significantly different (p<0.05, ANOVA). Species richness (n=68) was highest in tea estate while species heterogeneity (H’=3.612) and evenness (J’=0.872) were highest in home gardens. Percentage of endemic birds (25.6%) and percentage of migrant birds (12.8%) were highest in the forest and percentage of resident birds (74.6%) was highest in home gardens. The bird species composition in tea estate was highly comparable to that of home gardens (Cj=0.58). Percentage of openland birds (23.5%) was highest in tea estate whereas percentage of forest birds (59%) was highest in forest reserve. In addition, certain specialists were found exclusively within the forest. The higher diversity recorded, in human-modified landscapes has caused by its location in a closer proximity to forested areas and the wider array of different habitat types present. Therefore, such human-modified land-uses contribute for avifaunal conservation in the country. Yet, the long term impacts of such landscapes should be studied further.