Journal of Threatened Taxa | www.threatenedtaxa.org | 26 October 2025 | 17(10): 27782–27784

 

ISSN 0974-7907 (Online) | ISSN 0974-7893 (Print) 

https://doi.org/10.11609/jott.9805.17.10.27782-27784

#9805 | Received 31 March 2025 | Final received 05 September 2025 | Finally accepted 10 October 2025

 

 

Water Monitor Varanus salvator predation on a Hog Deer Axis porcinus fawn at Kaziranga National Park, Assam, India

 

Saurav Kumar Boruah 1, Luku Ranjan Nath 2, Shisukanta Nath 3 & Nilutpal Mahanta 4       

 

1,4 House no 29, M.L. Baruah Road, Silpukhuri, Guwahati, Assam 781003, India.

2 Narengi Kenduguri, Guwahati, Assam 781026, India.

3 Kaziranga Tourism Trade Welfare Society, Kohora, Assam 785609, India.

1 skboruah19@gmail.com, 2 lukuranjan83@gmail.com, 3 shisukanta11@gmail.com, 4 nilutpal.mahanta1@gmail.com (corresponding author)

 

 

Editor: S.R. Ganesh, Kalinga Foundation, Agumbe, India. Date of publication: 26 October 2025 (online & print)

 

Citation: Boruah, S.K., L.R. Nath, S. Nath & N. Mahanta (2025). Water Monitor Varanus salvator predation on a Hog Deer Axis porcinus fawn at Kaziranga National Park, Assam, India. Journal of Threatened Taxa 17(10): 27782–27784. https://doi.org/10.11609/jott.9805.17.10.27782-27784

  

Copyright: © Boruah et al. 2025. Creative Commons Attribution 4.0 International License. JoTT allows unrestricted use, reproduction, and distribution of this article in any medium by providing adequate credit to the author(s) and the source of publication.

 

Funding: None.

 

Competing interests: The authors declare no competing interests.

 

Acknowledgments: Authors are thankful to Kaziranga National Park and Tiger Reserve authority, and Kaziranga Tourism Trade Welfare Society.

 

 

The Water Monitor Lizard Varanus salvator is a large-growing, carnivorous reptile that is widespread in  southern and southeastern Asia (Quah et al. 2021). It is the largest lizard found in India (Ahmed et al. 2009). It is a Schedule I species under the Wildlife (Protection) Act, 1972 in India. It is listed in Appendix II of CITES (Chatterjee & Bhattacharyya 2015), and has been categorised as ‘Least Concern’ in the IUCN Red List of threatened species (ver. 3.1). The water monitor is an opportunistic animal and is semi-aquatic in nature, found in a variety of natural, and human-influenced habitats (Pal & Chatterjee 2022). It is both a predator and a scavenger, which feeds on invertebrates, fishes, turtles, snakes, lizards, small mammals, birds, and their eggs (e.g., rats), as well as carrion (e.g., Das 2010; Briggs-Gonzalez et al. 2022).

Kaziranga National Park and Tiger Reserve (26.47–26.79o N; 92.59–93.69o E; 1,055 km2) is located across Golaghat, Nagaon, and Biswanath districts of Assam (NTCA 2025). Famous for the One-horned Rhinoceros, it is a UNESCO World Heritage Site and a popular tourist destination. With diverse habitats present, Kaziranga National Park serves as an ideal home for reptiles, although it has not been extensively studied due to difficult terrains and the presence of many large mammalian species (Vignesh et al. 2023). The Water Monitor V. salvator and Bengal Monitor Varanus bengalensis lizards are among the most visible limbed reptiles of Kaziranga National Park (Pal & Chatterjee 2022).

On the evening of 5 April 2023, during a safari at the central range (Kohora) of Kaziranga National Park, a female Hog Deer Axis porcinus was observed exhibiting distress behaviour with continuous distress call under a tree. The deer was seen trying to chase away some other animal by forcefully beating its forelimbs on bushes and ground. Upon closer observation with binoculars and cameras, the team could see a tail. After repositioning the jeep, the team was able to identify the animal as a Water Monitor Lizard V. salvator, despite its head being partially obscured by vegetation. After waiting for some time, as the lizard started to move, the team observed a hog deer fawn in its mouth (Image 1). The animal could be identified as a hog deer fawn by looking at the spots on the lateral sides of the body. Kaziranga National Park doesn’t fall within the natural distribution range of the superficially similar-looking Spotted Deer Axis axis. But the Hog Deer fawns have white spots on the sides of the body, and hence the animal could be identified as a Hog Deer fawn. The monitor lizard was feeding on the fawn. The average Hog Deer Axis porcinus fawn weighs approximately 1–1.5 kg and measures 40–50 cm in length at birth (Vignesh et al. 2023). In contrast, adult water monitor lizard  like the one observed at Kaziranga, can weigh over 10 kg and exceed 200 cm in total length, making it physically capable of preying upon such a fawn (Ahmed et al. 2009; Pal & Chatterjee 2022).

Water Monitor Lizard V. salvator on account of being a large-growing, predator lizard having a reasonably large distribution range, and possible anthropophilic nature, is a rather well-researched species, compared to other lizards, including other monitors in Asia (Briggs-Gonzalez et al. 2022). Closest of such vital feeding events was a report of predation on a kitten by V. salvator in Indonesia (Mardiastuti & Kusrini 2023). Upon consulting recent literature on the diet of the V. salvator complex (Mahaprom & Kulabtong 2018; Yu et al. 2021; Briggs-Gonzalez et al. 2022; Du et al. 2022; Guerrero-Sanchez et al. 2022, 2023; Zdunek  & Kolenda 2022; Han 2023; Mardiastuti & Kusrini 2023; Trivalairat & Srikosamatara 2023; Zdunek et al. 2024 and references therein), it was found that this is probably the first precise record of a water monitor preying on a Hog Deer and hence worth placing on record.  

 

 

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