Article

Mijanur K. M. Rahman, PhD student of the Department of Bioecology, Hygiene and Public Health, Kazan Federal University; e-mail: rahman.bgd@outlook.com
Ilgizar I. Rakhimov, Dr. Sc., Professor and Head of the Department of Bioecology, Hygiene and Public Health, Kazan Federal University; e-mail: rakhim56@mail.ru
M. Monirul H. Khan, Professor of the Department of Zoology of the Jahangirnagar University, Bangladesh; e-mail: mmhkan@hotmail.com

Rahman M.K.M., Rakhimov I.I., Khan M.M.H. 2016. Microhabitat ecology of semi-aquatic Varanus flavescens (Reptilia: Varanidae) in altered habitats. Nature Conservation Research 1(3): 95–100. https://dx.doi.org/10.24189/ncr.2016.031

A potential microhabitat is very important for the survival and successful reproduction of any wildlife species. In this study we assessed the microhabitat characteristics of Varanus flavescens in the human altered ecosystems of Chalan beel area, Baraigram, Natore by flowing the Visual Encounter Survey method and by using several important material. A semi-aquatic microhabitat of canal and river was preferred by the species as compared to other identified microhabitats. The slow moving water of the river and canal was fresh and somewhat cloudy in character but stagnant water of the pond and beel (floodplain) was semitransparent having lots of phytoplankton and zooplankton. The soil was mostly silty clay. As the study species is cold blooded, the environmental variables like soil, air and water temperatures inside and outside of the microhabitat play major roles for their activity patterns. In order to regulate their body temperature, during a hot sunny day they were more active within the shady area of the microhabitats but at dawn and dusk they were more seen in the sunny areas where temperature was relatively higher. In winter months, the monitor lizards were almost inactive. During that time of the year they live inside the burrow to avoid the extreme cold and foggy weather but during heavy sunshine they come outside of the hole for thermoregulation purpose for a certain time. We noticed that extensive agricultural practice and the excessive use of insecticides may be having a detrimental effect on the microhabitat features important to this semiaquatic lizard. Still the study species is more seen in the human altered ecosystems of Bangladesh. So, to ensure their existence in our close proximity there is an urgent need to create consciousness of the people regarding this beneficial non-venomous species and their respective microhabitat.

altered ecosystems, Bangladesh, habitat preferences, microhabitat, Varanus flavescens, yellow monitor

Received: 13.10.2016

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