3rd URS-ZEM - 2017
Permanent URI for this collectionhttp://repository.kln.ac.lk/handle/123456789/16655
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Item 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.Item An assessment of the avifaunal diversity in Hapugastenne estate of Ratnapura District, Sri Lanka(Department of Zoology and Environmental Management, University of Kelaniya, Sri Lanka, 2017) Fernando, G.K.; Perera, S.J.An avifaunal survey was conducted at Hapugastenne Tea Estate (1302ha), Ratnapura, Sri Lanka from November to December 2015 with objectives of assessing the bird diversity within different habitats and documenting threats to biodiversity. Bird populations were sampled in 39 line transects and 17 point counts for terrestrial and aquatic habitats respectively representing eight habitat strata (tea fields, home gardens, scrublands, secondary forests, natural forests, stream-side vegetation, riverine forests, and water-logged areas) within the estate, replicated in its nine divisions. Transects were conducted during the morning between 07:00 and 09:00 hrs. A total of 91 species, including nine Sri Lankan endemics and nine winter visitors were recorded, which included one globally and six nationally near threatened species. Estimates of relative abundance indicated a high degree of rarity, with only few abundant species, the red-vented bulbul being the most abundant. Among the habitats, the highest species richness (39) was recorded in stream-side vegetation where Simpson’s diversity index (0.947) was also the highest, while the Shannon-Wiener diversity index (H’=3.247) is marginally second to tea fields (H’=3.382), where the evenness was the highest (J=0.994). Interestingly, the Shannon-Wiener diversity and the evenness of the secondary forest fragments were comparable to those of home gardens (H’=2.591; J=0.795 and H’=2.515; J=0.791 respectively). The results of the feeding guild analysis indicated a greater abundance of the insectivore guild was greater in tea field than in other habitats. In contrast, the relative abundance of frugivore guild was higher in the natural and secondary forests. Cluster analysis indicated a highly dissimilar species composition in scrublands compared to other habitats, while tea fields and home gardens were very similar in their avifauna. The study revealed that this managed landscape provides a diversity of niches maintaining the natural biodiversity to a certain extent. Nevertheless, 14 alien invasive species (nine plants and five animals) were identified from the area among several other threats to the biodiversity. Increasing plant diversity, introduction of shade trees and connecting remnant natural habitat patches via stream reservations are recommended to conserve and enhance the avifaunal diversity in the study area.