A preliminary study of the effects of enrichment on the activity and spatial distribution of captive monitor lizards in Nakhon Ratchasima Zoo, Thailand https://doi.org/10.12982/VIS.2024.015

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Xin Huo
Kirati Kunya
Nirattisai Ritthijan
Pimchanok Lohtongkam
Catthareeya Sukwan
Sompong Wongma
Prayuth Kusonrat
Panich Kumroptanasan


The monitor lizard (Varanus salvator) has the widest distribution among all extant varanids found across South and Southeast
Asia. However, behavioral studies on captive monitor lizard have not been well-documented. The objective of this research
was to investigate the effects of enrichment items on the activity and spatial distribution of captive monitor lizards. The study
involved three adult captive Black water monitors (Hiea dam), three adult Roughnecked monitors (Ngu-hao Chang), and
two adult Dumeril’s monitors (Tut-too) in outdoor enclosures. Three treatments were administered: control (no enrichment
item), cone (enrichment item), and takraw (enrichment item: a rattan ball). The frequency of activity and spatial distribution
of three species of monitor lizards were recorded. The results showed that the percentages of activity and spatial distribution
of three species of monitor lizards were not significantly affected by the enrichment items (P > 0.05). However, there were
significant differences only in lying behavior between the Hiea dam, Ngu-hao Chang, and Tut-too monitors (P < 0.05). In
conclusion, the general behaviors of captive Hiea dam, Ngu-hao chang, and Tut-too monitor lizards were similar, and their
spatial distribution was also similar. The behavior and spatial distribution of captive monitor lizards were not affected by the
enrichment items.

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How to Cite
Huo, X., Kunya, K. ., Ritthijan, N. ., Lohtongkam, P. ., Sukwan, C. ., Wongma, S. ., Kusonrat, P. ., & Kumroptanasan, P. . (2023). A preliminary study of the effects of enrichment on the activity and spatial distribution of captive monitor lizards in Nakhon Ratchasima Zoo, Thailand: https://doi.org/10.12982/VIS.2024.015. Veterinary Integrative Sciences, 22(1), 193–2.5. Retrieved from https://he02.tci-thaijo.org/index.php/vis/article/view/263668
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