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Activity Patterns and Feeding Ecology of the Semi-Aquatic Varanus flavescens (Reptilia: Varanidae)

K. M. Mijanur Rahman, Ilgizar Iliazovic Rakhimov


The study was conducted on activity patterns and feeding ecology of semi-aquatic yellow monitor (Varanus flavescens) in the Chalan Beel area of Bangladesh by following focal sampling method. Overall, V. flavescens spent highest proportion (37.73 ± 0.65) of their active time in moving in search of food and lowest proportion (3.05 ± 0.05) of time in conflicting. Maximum (22.80 ± 3.19) and minimum (5.82 ± 1.06) moving activity were recorded in the month of August and December respectively. Two peak feeding times; from 6.30 AM to 10.30 AM and from 3.00 p.m. to 4.30 p.m. were recorded throughout the day. Total 15 prey groups were recorded as yellow monitor’s diet. The diet consisted mainly of beetles, which comprised 15% of the number of prey items in stomach samples. Others diet comprises of spider, dragonfly, water scorpions, mole crickets, crickets, ants, fresh water crabs, grasshopper, frog, small fish, house mouse and bird eggs. Most of the activities of V. flavescens varied significantly (χ2 test, P < 0.05) in different month in response to changing weather conditions. During heavy cold V. flavescens shows basking activity to regulate their body temperature and the highest proportion (50.48 ± 3.03) of basking activity was recorded in December. The population of V. flavescens is decreasing at an alarming rate all over Bangladesh. This warrants for further study regarding the ecology and conservation of the yellow monitor.


yellow monitor; Varanus flavescens; activity; diet; Bangladesh

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