RESEARCH ARTICLE

DISTRIBUTION OF THE JUNGLE CROW (Corvus levaillantii LESSON, 1831) AND THEIR POTENTIAL THREATS TO BIODIVERSITY IN HORTON PLAINS NATIONAL PARK, SRI LANKA.

Abstract

Distribution of the Jungle Crow (Corvus levaillantii Lesson, 1831) and their potential threats to biodiversity was studied at the Montane Cloud Forests of Horton Plains National Park, of Nuwara Eliya District at the Central Highlands of Sri Lanka, from September 2015 to March 2017. This species is distributed in every terrestrial habitat throughout Sri Lanka. To study distribution of the crow, three main habitats were identified as Forest habitat, Grassland habitat, and Human-induced habitat. Three, 100 m fixed line transacts were marked in each of the habitats using a global positioning system device (GPS). Field observations were conducted on three consecutive days each month, while travelling along transacts, from 0600h to 1800h. Birds were observed directly or through a 10x50 binocular. Meanwhile, number of visitors walked through transects was counted. Opportunistic observations were carried out, to investigate threats for the other animals. Maximum population of C. levaillantii was present at Human-induced habitat, 45.95±18.59 (Mean ± Standard deviation). Minimum population was recorded from Grassland habitat 30.26 ± 16.93(M ± SD). In the Forest habitat C. levaillantii population was 33.05 ± 16.97 (M ± SD). Population of C. levaillantii recorded at Human-induced habitat, positively correlated with the number of visitors per hour (Pearson correlation= 0.887, p-value < 0.05). Though there were sign boards and garbage bins, crows always inhabited in Human-induced habitat. Endemic lizards; Calotes nigrilabris, Ceratophora stoddartii and Cophotis ceylanica are highly attacked and endemic birds such as Gallus lafayettii, Eumyias sordidus and Pycnonotus penicillatus were harmed by C. levaillantii in high numbers. Raptor birds such as Haliastur indus, Circus macrourus, Pernis ptilorhynchus and Falco tinnunculus, were attacked by the crow. According to present findings it can be concluded, that the Horton Plains National Park is invaded by Jungle Crow. Large number of crows is a major threat to endemic animals. Increased number of crows is an indicator of pollution, because they are scavengers in the food chain. To establish the protection of fauna in this important Montane Cloud Forest, admissible methods to control the number of C. levaillantii are needed.

Keywords: Corvus levaillantii, distribution, Horton plains national park, tropical montane cloud forest, threats.

How to Cite: Chandrasiri,P.H.S.P,Dharmarathne,W.D.S.C,Lakmal,S.B.R, Mahaulpatha,W.A.D, (2017). DISTRIBUTION OF THE JUNGLE CROW (Corvus levaillantii LESSON, 1831) AND THEIR POTENTIAL THREATS TO BIODIVERSITY IN HORTON PLAINS NATIONAL PARK, SRI LANKA..WILDLANKA, 5(2):Pages 073-077

Published On:2017-07-31

Download