Amphibian abnormalities and threats in pristine ecosystems in Sri Lanka

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G.K.V.P.T. Silva
W.A.D. Mahaulpatha
Anslem de Silva


Amphibian abnormalities are caused by numerous etiologies prevailing in the environment.  Since amphibians are good bio indicators of the environment, amphibian abnormalities are popularly known as a veritable ecological screening tool to assess ecosystem health.  The present study was carried out encompassing within and outside the Horton Plains National Park areas, from January to November 2017.  Distribution of amphibian morphological abnormalities were assessed in and around the five lentic water bodies through gross visual encounter.  Six quadrates of 1m×2m were randomly placed in each sampling site.  Frequency and composition of amphibian abnormalities were assessed in a total of 694 amphibians, belonging to four families and 11 species.  Thereby, 4.5% and 80.87% abnormality indexes were accounted for respectively within and outside the park, comprehended surficial abnormalities, ectromelia and femoral projection abnormality types.  Surficial abnormalities were the most predominant in both localities, generally occurring at the hind limb region of pre-mature stages of Taruga eques.  Two lentic water bodies were identified as “abnormality hotspots†within and outside the Horton Plains National park; however, a multiplicity of possible combinations of potential causes of abnormalities were present in the environment.  Hence, finding the exact causes of amphibian abnormalities are an extremely difficult exercise in the field.  

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Author Biographies

W.A.D. Mahaulpatha, Department of Zoology, Faculty of Applied Sciences, University of Sri Jayewardenepura Gangodawila, Nugegoda, Sri Lanka.

As a researcher and a professor in zoology in University of Sri Jayewardenepura, Prof. W.A.D Mahaulpatha has executed many researches in wildlife conservation and management including ornithology, herpetology and mammalogy and have more than hundred publications. As result of that she was got the Presidential award involuntarily in 2018.

Anslem de Silva, 315/1, Dolosbage Road, Gampola (Central Province), Sri Lanka.

Anslem de Silva, MSc. DSc. has contributed approximately 425 papers. This include app 50 books, the latest "Naturalist Guide to Reptiles of Sri Lanka' published in UK, 2017. Anslem received Presidents award for Scientific Publications four times. He is the current Regional Chairman of the Crocodile Specialist Group IUCN for South Asia and Iran.


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