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

Reference to article

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.

Section Short Communications

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

Artice information

Received: 13.10.2016

The full text of the article

Ali Reza A.H.M., Sourav M.S.H. 2010. Varanus flavescens (Yellow Monitor): distribution and reproduction, Natural history notes. Herpetological Bulletin 112: 38–42.
Auffenberg W., Rahman H., Iffat F., Perveen Z. 1989. A Study of Varanus flavescens. Hardwicke and Gray (Sauria varanidae). Journal of the Bombay Natural History Society 86 (3): 286–307.
Dickinson H.C., John E.F., Lenton S.M. 2001. Microhabitat use by a translocated population of St. Lucia whiptail lizards (Cnemidophorus vanzoi). Animal 4: 143–156.
Ghimire H.R., Phuyal S., Shah K.B. 2014. Protected species outside the protected areas: People's attitude, threats and conservation of the Yellow Monitor (Varanus flavescens) in the Far-Western Lowlands of Nepal. Journal for Nature Conservation 22 (6): 497–503.
Ghimire H.R., Shah K.B. 2014. Status and habitat ecology of the yellow monitor, Varanus flavescens, in the southeastern part of Kanchanpur district, Nepal. Herpetological Conservation and Biology 9 (2): 387−393.
Gibbons J.W., Scott D.E., Ryan T.J., Buhlmann K.A., Tuberville T.D., Metts B.S., Greene J.L., Mills T., Leiden Y., Poppy S., Winn C.T. 2000. The global decline of reptiles, déjà vu amphibians. Bioscience 50: 653–666.
Hayer W.K., Donnelly M.A., McDiamid R.W., Hayekand L.C., Foster M.S. (eds.). 1994. Measuring and Monitoring Biodiversity, standard methods for amphibians. Washington: Smithsonian institution Press. 364 p.
Ibrahim A.A. 2000. A radiotelemetric study of the body temperature of Varanus griseus (Sauria: Varanidae) in Zaranik Protected Area, North Sinai, Egypt. Egyptian Journal of Biology 2: 57–66.
Islam M.A. 2009. Varanus flavescens. In: Encyclopedia of Flora and Fauna of Bangladesh, Amphibians and Reptiles. Dhaka, Bangladesh: Asiatic Society of Bangladesh. Vol. 25. P. 103–104.
IUCN Bangladesh. 2015. Red List of Bangladesh Volume 4: Reptiles and Amphibians. Dhaka, Bangladesh: IUCN, International Union for Conservation of Nature, Bangladesh Country Office. 320 p..
Karki A., Bista R., Humagain S. 2008. Distribution, Behavioral Ecology and Present Status of Varanus flavescens (a literature review paper) in Nepal. The Initiation 2 (1): 49–54.
Khan M.M.H. 2008. Protected Areas of Bangladesh – A Guide to Wildlife. Dhaka, Bangladesh: Nishorgo Program. 290 p.
Losos J.B., Greene H.W. 1988. Ecological and evolutionary implications of diet in monitor lizards. Biological Journal of the Linnean Society 35: 379–407.
Razi H.A., Baki M.A., Alam S.M.I. 2014. Varanus flavescens (yellow monitor): Thermoregulation. The Herpetological Bulletin 129: 27–27.
Rahman K.M.M., Khan M.M.H., Rakhimov I.I. 2016. Microhabitat Use by the Herpetofauna in Mixed-evergreen and Deciduous Forests of Bangladesh. Journal of Pharmaceutical, Biological and Chemical Sciences 7 (1): 841–858.
Mayes P.J., Thompson G.G., Withers P.C. 2005. Diet and Foraging Behavior of the Semi-aquatic Varanus mertensi (Reptilia: Varanidae). Wildlife Research 32: 67–74.
Visser G. 2004. Varanus flavescens. In: E. Pianka, D.R. King (eds.): Varanoid Lizards of the World. Indiana: Indiana University Press. P. 179–183.
Zug G.R., Leviton A.E., Vindum J.V., Wogan G.O.U., Koo M.S. 2004. Checklist of the Myanmar Herpetofauna. Myanmar Herpetological Survey Project. 105 p.