Browsing by Author "Gunawardena, M. P."

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Assessing the diversity and conservation needs of order Squamata in Mandaramnuwara, Sri Lanka
(Faculty of Science, University of Kelaniya Sri Lanka, 2024) Rajarathna, M. D. G. H. A.; Gunawardena, M. P.; Wijegunawardhana, A. H. C.; Jayaweera, C. L.; Sandamali, A. D. P. H.; Jayasuriya, R. T. P.; Hettiarachchi, C. J.
Mandaramnuwara, is a village located on the eastern slopes of the Piduruthalagala mountain range in Sri Lanka. This area harbours significant faunal diversity yet lacks scientific studies on the diversity of the Order Squamata, which includes snakes and lizards. We conducted a visual encounter survey over a 15-month period from October 2022 to December 2023, aimed to document the diversity of Squamates in areas outside the protected zone, where these species face significant threats from human activities and vehicle movements. The total number of 15 visits (once a month) were carried out during daylight hours (07:00 h to 18:00 h) along a 10 km road (starting point 07.05861N, 080.76875E, ending point 07.04239N, 080.76155E), with an elevation gradient from 900 m to 1600 m, covering a five-meter span on both sides of the road. A total of 18 species belonging to six Families were recorded. Among these, 15 species, which is 83.33% of the total, were endemic, and 12 species which is 66.67% of the total, were nationally threatened. The threatened species included the critically endangered Cyrtodactylus fraenatus, the endangered Calotes nigrilabris, Cophotis ceylanica, Ceratophora stoddartii, Aspidura trachyprocta, Rhinophis blythii, Rhinophis melanogaster, and Hypnale nepa. Other threatened species recorded were the vulnerable Dendrelaphis caudolineolatus, Aspidura brachyorrhos, Aspidura ceylonensis, and Oligodon sublineatus. Additionally, two endemic species were near threatened: Calotes liolepis, Bungarus ceylonicus, and Ahaetulla nasuta, which is of least concern. Observations noted seven instances of road kills, affecting both snake and lizard populations. Given the high level of endemism and the presence of numerous threatened species, it is crucial to raise awareness within the local community to mitigate unnecessary fears and killings, particularly of snakes. In conclusion, the findings of this survey highlight the critical need for targeted conservation efforts in Mandaramnuwara. By raising awareness and integrating the local community into conservation initiatives, the area can be effectively preserved while promoting sustainable tourism. The documentation of Squamata diversity in this region emphasises the importance of continued research and conservation strategies to protect its biodiversity.
Comparison of the floral diversity at Beddagana and Diyasaru Urban Wetlands Parks, Colombo, Sri Lanka
(4th International Research Symposium on Pure and Applied Sciences, Faculty of Science, University of Kelaniya, Sri Lanka, 2019) Senevirathne, G. G. G. R. D.; Janaarthan, G.; Sivaseelan, M.; Rathnayake, H. M. C. L.; Gunawardena, M. P.
The district of Colombo is endowed with a variety of wetlands, mainly compromised of abandoned paddy fields, man-made lakes, and marshes. Since the 1980s, Colombo has lost almost 60% of its wetland area. Losing an average of 1.2% of its area per year, wetlands at present only make up 20 km2 of Colombo. Some of the main threats to wetlands and its plant diversity include anthropogenic activities and the rapid spreading of alien invasive species. A research was conducted to measure the diversity of plants in Beddagana Wetland Park and Diyasaru Wetland Park, in the Colombo Metropolitan area. The main objective of this study was to compare the floral diversity between the two urban wetland parks. The quadrat method was used for sampling (trees: 25 m2, saplings: 1 m2). Sampling was done at three habitats at each location; the first habitat being at the edge of the waterbody, the second being ten meters away from the waterbody and the third being twenty meters away from the waterbody. A single plot was placed in each habitat and three quadrats were placed in each plot. The 25 m2 quadrat was used to count plants taller than 1 meter and the 1 m2 quadrat was used to count plants shorter than 1 meter. The total number of individuals of each plant species inside each quadrat was recorded. A total of 13 species at Beddagana Wetland Park and 17 Species at Diyasaru Wetland Park were observed. The most common species observed at Beddagana Wetland Park was an alien invasive species; Annona glabra, with a relative abundance of 31.13%. The most common species observed at Diyasaru Wetland Park was Commelina diffusa, with a relative abundance of 29.77%. Simpson’s index and Shannon Diversity Index values were 0.8176/1.9668 for Beddagana Wetland Park and 0.7999/1.9310 for Diyasaru Wetland Park. The Shannon diversity values depict low species richness and species evenness in the area, which is a result of the raid of invasive floral species. Similarly, there is no key variance in the floral diversity at both sites. However, further studies and monitoring are recommended to determine the floral diversity at the Colombo wetlands. Furthermore, prompt bearable measures are needed to control the rapid spreading of invasive flora in the wetlands
Preliminary survey on avifaunal diversity at Bellanwila-Attidiya Sanctuary, Sri Lanka
(4th International Research Symposium on Pure and Applied Sciences, Faculty of Science, University of Kelaniya, Sri Lanka, 2019) Dissnayake, D. M. D. S. M.; Jayasinghe, V.; Gunawardena, M. P.
Sri Lanka shelters a rich avifaunal diversity and the Bellanwila – Attidiya sanctuary (BAS) is of much importance as a habitat for birds. The diurnal avifaunal diversity was studied along the Nedimala canal of the Weras Ganga belonging to the BAS, from July 2016 to February 2017, using the fixed distance line transect method. All birds seen within one hundred meters on either side of the canal were recorded, at three different sessions of the day (morning 6:30-8:30 h, noon 11:30-1:30 h and evening 3:30-5:30 h). A total number of 2592 of individuals belonging to 62 bird species, 29 families and fifteen orders were recorded during the study period. These included the globally near-threatened (NT) Spot Billed Pelican (Pelicanus philippensis). Only migratory species recorded during the months of January and February was the Indian Paradise Flycatcher (Terpsiphone paradisi). Using the recorded data, the relative abundance of each bird species was calculated. The calculated relative abundance indicates that the House Crow (Crous splendens) was the most common bird (10.61) followed by Little Comorant (Microcarbo niger) (5.86), Rose Ringed Parakeet (Psittacula krameria) (5.71) and Brahminy Kite (Haliastur indus) (5.02). The Brown Shrike (Lanius seristatus) was the least observed bird (0.04). Furthermore, the calculated diversity index values depict a relatively high diversity of 3.62 for the Shannon index and 0.9625 for Simpson’s Index. According to the records, it was revealed that birds are more active during the morning hours. Even though the study site is in close proximity to densely populated residential areas; it still provides vital habitat to a large number of bird species. Although, due to the increasing number of invasive species and pollution around the canal, a decrease in the avifaunal composition, especially considering aquatic bird species, has been observed which ensures that measures to protect and conserve the Bellanwila – Attidiya Sanctuary should be taken
Preliminary survey on avifaunal diversity in an urban ecosystem: Malabe,Sri Lanka
(4th International Research Symposium on Pure and Applied Sciences, Faculty of Science, University of Kelaniya, Sri Lanka, 2019) Dissanakayake, D. M. D. S. M.; Gunawardena, M. P.; Hathurusinghe, D.
Permanent changes caused due to urbanization have resulted in wide-ranging impacts on the avifauna. Altered environmental conditions such as air pollution, artificial light, garbage pollution, different predation pressures and anthropogenic disturbances have pushed the avifauna to its range of tolerance. Therefore, a study was designed to ascertain the avifaunal species diversity of an urban ecosystem: Malabe, with the objective of assessing the contribution of local habitats for the conservation of avifaunal species. Three different habitat types viz. Canal along with the terrestrial habitat, habitat with vegetation and urbanized/home garden habitat, were studied using 500 m transects, and bird species within 50 m on either side were recorded three times per day, in the morning (6:30 – 8:30), noon (11:30 - 1:30) and in the evening (15:00 – 17:00), within a period of 12 months from November 2016 to October 2017. As per observations, 8269 birds belonging to 35 species, 21 families and 11 orders were recorded within the area. The Simpson’s index and Shannon diversity index were 0.91/3.22, 0.99/2.65 and 0.99/2.53 at the three habitats respectively. The most dominant species recorded were the House crow (Corvus splendens), Spotted Dove (Spilopelia suratensis), Rose-ringed Parakeet (Psittacula krameria), Red-vented Bulbul (Pycnonotus cafer) and Yellow-billed Babbler (Turdoides affinis) with a relative abundance of 15.82%, 10.59%, 7.66%, 7.62%, and 6.35% respectively. Globally near threatened, Spot-billed Pelican (Pelicanus philippensis) was the least recorded species during the study with a relative abundance of 0.04%, which was recorded only during floods in the area. The least diversity was recorded in the urbanized area with a Shannon diversity index of 2.53 and the highest (3.22) was recorded in the canal along with the terrestrial habitat. Therefore, it is evident that these urban habitats act as wildlife refuges in the area and neutralizes the negative effects of urbanization on birds to a certain extent. Thus, proper conservation plans should be implemented through proper research to manage and improve the existing local habitats and thereby protect the avifauna