Browsing by Author "Thilakarathne, K.G.D.D."

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    Avifauna at Warathenna-Hakkinda Declared Environmental Protection Area (EPA) in Kandy, Sri Lanka
    (Uva Wellassa University of Sri Lanka, 2018) Thilakarathne, K.G.D.D.; Lakkana, P.H.T.; Hirimuthugoda, G.N.; Kumburegama, N.P.S.
    Sri Lanka has vast diversity and endemicity of both flora and fauna. The Mahaweli River is the longest river and it originates from the central highlands and flows through the wet, intermediate and dry zones of the country. It helps sustain a rich biological diversity. However, large extents along the river are yet to be explored for its rich biodiversity. One such area along the Mahaweli River at Gatambe, Warathenna in the Kandy District appears to harbor a rich biodiversity and hence recently declared as an Environmental Protection Area (EPA). The present study was carried out to investigate and prepare a comprehensive checklist of the avifauna in this declared EPA which may be used for future conservation efforts. The study was carried out from June 2016 to May 2017 along an approximately 2 km stretch of the Mahaweli River in the declared EPA starting from the Gatambe main bridge (7° 27213’N, 80° 60463’E) to Dodangwela Suspension Bridge (7° 287915’N, 80° 608630'E). Field sampling was carried out once a week during the study period in the declared EPA and sampling was conducted to encompass all habitat types. A point count method was carried out along 100 m transect to identify the birds and a maximum of 30 minutes was spent at each point. Birds were identified using direct observations with the aid of a 10 x 42 binocular and through birdcalls. Bird guides were used to confirm the identifications. A total of 74 bird species belonging to 61 genera were encountered from the study site. Among these, seven species were endemic while seven were migratory. Five percent of the birds recorded were raptors and most of them were canopy and sub canopy dwellers associated with riverine forests and islands. Most of the birds encountered use this area as their roosting and nesting areas. According to the National Red List (2012), 62 of the species recorded during the study are categorized as “Least Concerned”, two species as “Vulnerable” (Sri Lanka wood pigeon, Sri Lanka Hill mynah), three as “Near Threatened” (Oriental dwarf kingfisher, Cinnamon Bittern and Black crown night heron), one as “Endangered” (Alpine swift) and another as “Critically Endangered” (Rock Pigeon) in their natural habitats. According to the Global Conservation Status, 72 of the species recorded during the study are categorized as “Least Concerned” while one species as “Vulnerable” (Sri Lanka wood pigeon) and one as “Near Threatened” (Sri Lanka Hill mynah). These habitats along the Mahaweli River at Warathenna appear to aid in sustaining a rich bird community so future conservation of this declared EPA will help create a safe haven for the avifauna.
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    Thermal Ecology of an Endemic Sri Lankan Kangaroo Lizard (Otocryptis wiegmanni) tinder Wild and Captive Conditions
    (Uva Wellassa University of Sri Lanka, 2018) Lakkana, P.H.T.; Thilakarathne, K.G.D.D.; Sampath, J.K.H.; Meegaskumbura, M.
    Thermal ecology of Sri Lankan endemic agamid lizard species is poorly known, but vital for their conservation. This study examined the thermal ecology of Otocryptis wiegmanni both under wild and captive conditions. External body temperature (Tb), corresponding environmental temperature (Te), sex and behaviour of 121 lizards were recorded. In captivity Tb and Te were recorded at one hour time intervals within 24 hours for 10 days. For the wild condition, Tb and Te were randomly collected both in day and night time. In the wild, Tb was significantly lower than Te (p > 0.05) and mean difference was -1.59 °C. There is a positive correlation between Tb and Te (r = 0.816, p < 0.05). The best fit regression line is Tb = 5.86 + 0.695Te (R2 = 66.6%). Regression coefficient (0.695) is significant (p < 0.05). Although in captivity, Tb was significantly lower than Te (p > 0.05) and mean difference was 0.91 °C. Tb and Te shows strong positive correlation (r = 0.914, p < 0.05). Best fit regression line is Tb = 1.95 + 0.886Te (R2= 83.6%). Regression coefficient (0.886) is significant (p < 0.05). Moreover in both wild and captive conditions, Tb of males and females were not significantly different. Regression coefficients of both wild and captivity differ from the theoretical value of zero required for thermoregulation verify that O. wiegmanni is a thermoconformii)) species. The Tb for this population ranged between 20 - 26.5 °C. We never observed O. wiegmanni showing obvious basking behaviour, may be a reason for having a lower Tb than Te. Activities such as territorial and courtship display, mating, egg laying, and feeding occurred during daytime while they are dormant at night and mostly perch above ground. Moreover, O. wiegmanni is adept at tracking environmental temperature by selecting appropriate thermal microhabitats to maintain their body temperature within the optimal level. This study provides a basis and emphasizes the necessity of in-depth thermal ecological studies on Sri Lankan agamids.