Status Of The Bengal Monitor Lizard

Chitwan National Park is the first national park of Nepal, with an area of 952.63 square km. This national park covers the main areas of the Chure hills, Rapati, Narayani, and Riu Rivers. The Sal forest covers about 70 per cent of this national park's forest area. This national park was established in 1973, and the intermediate zone was established in 1996. Chitwan National Park is also a World Heritage Site and has other lakes in its central region, including the Ramsar site of Bishajari Lake. It is a rich natural area in the Tarai, the subtropical southern part of Nepal.

This national park is home to 68 species of mammals, 544 species of birds, and 56 species of fish. Among them is the Bengal Monitor Lizard, also known as the Indian monitor or common monitor lizard. Varanus bengalensis is the scientific name of this reptile, known as Gohoro in Nepali. I am visiting this national park for wildlife photography. During my visit in 2024, I managed to see this reptile three times. I spotted it near a bush on the ground two times and on a tree once. I photographed this shy reptile, which hides in the bushes.

Other national parks and terrains in Nepal, primarily in agricultural areas, are also home to the Bengal Monitor Lizard. These reptiles are mainly distributed at lower altitudes, below 1500 meters. They can be found in moist forests situated in dry, semi-desert environments. They prefer forests with large trees. These monitors, being eurytopic and adaptable to a variety of habitats, are among the most widely distributed of their kind. The Bengal Monitor Lizard is also found in Nepal, India, Sri Lanka, Pakistan, Bangladesh, Eastern Iran, Burma, and Afghanistan.

The length of the Bengal Monitor Lizard is 75–100 cm from the tip of the snout to the tip of the tail. Males are usually larger than females. Its weight is around 7.2 kg. Young monitors are more colourful than adults. The belly is white, banded with dark crossbars, and shows brown or yellow. On the dorsal surface of young monitors, there are a series of yellow spots connecting dark transverse bars. Like other monitors, the Bengal Monitor Lizard has a snake-like tongue, which protrudes from time to time. The tongue primarily serves as a sensory organ and does not play a significant role in transporting food down the belly.

Bengal monitor lizards are often solitary and are usually found on the ground. But this reptile is also able to climb trees. The young live in trees to avoid predators. On the ground, these monitors occasionally stand on their hind legs, especially during conflicts between males. These monitors are excellent swimmers and can stay submerged for at least 17 minutes.

Bengal monitor lizards often burrow in the ground, in crevices in rocks and buildings, or in holes in large trees. Like varanidae, they sleep at night and are active in the morning for hunting. During the winter season, they may take refuge in the colder parts of their distribution range and undergo a period of low metabolic activity. Their keen eyes can detect human movements up to 250 meters away.

Bengal Monitor Lizards are carnivorous, and their typical diet includes beetles, grubs, arthropods, scorpions, wasps, ants, and invertebrates. They also eat frogs, fish, lizards, snakes, mice, ground birds, and dead animals. They are polygynandrous, meaning that both males and females have numerous partners. Their main breeding season is from June to September. However, males start to show fighting behaviour in April. Females dig a nest hole on level ground or a steep bank and lay eggs inside the hole. They sometimes use termite mounds to nest. A single clutch contains about 20 eggs. Eggs hatch after 168–254 days of incubation, and only about 40–80 percent of eggs hatch. Young people are independent at birth and become reproductively mature at about 2.5 to 3 years of age.

According to Dr. Hem Bahadur Katuwal, a senior ecologist and assistant professor, the Bengal monitor lizard has a wide distribution in South and Southeast Asia. It mainly lives in forests, forest edges, bushes, wetlands, and agricultural areas. It is a carnivore species, feeding on both invertebrates and vertebrates, including carrion. Hunters hunt the Bengal monitor lizard for its skin and meat. Other threats include habitat loss and degradation, agrochemicals, and linear infrastructure such as roads. The IUCN Red List of Assessment classifies it as near threatened. In Nepal, it is widely distributed across lowland Nepal and is also found in some mid-hill regions. It is one of the least studied and least prioritised lizards in Nepal. So, detailed studies are needed.

The IUCN Red List classifies this species as least concern. People hunt this reptile for its skin, for consumption, and for medicinal purposes. The various myths and superstitions surrounding these monitors have exposed them to issues such as human-wildlife conflict and wildlife trafficking.

(The author is a wildlife photographer. The photos used in this article are by the author.)