The Three Crocodilians Of India

A gharial in the Chambal River. Image credit: Charles J. Sharp via Wikimedia Commons.

Crocodiles have always inspired our awe and triggered our primaeval fear instinct. These giants of the water have been part of thousands of folktales across the world, revered as deities in many cultures, and also featured in several thrilling documentaries and movies. India is no exception. Mythological tales from the country are replete with stories of the "makara," the Sanskrit name for the mugger crocodiles, a crocodile species widely distributed in India. However, India is home not just to the muggers but two more species of crocodilians who all belong to the Order Crocodilia. These are the saltwater crocodiles and the gharials. These reptilians are extremely important species of the aquatic ecosystems where they are found. While they might appear to dominate the aquatic realm they inhabit, human activities highly threaten them. Let us take a closer look at the three species of crocodiles found in India below and their current conservation status and threats:

Saltwater Crocodiles (Crocodylus porosus)

A saltwater crocodile in Bhitarkanika National Park. Image credit: Bodhan Nayek via Wikimedia Commons.

The world's largest reptilians, males of this species can grow as long as 20 feet and weigh as much as 1,500 kgs! Females are relatively much smaller, growing to around 10 feet long. The saltwater or estuarine crocodile has a much more widespread global distribution than the other two crocodilians of India. In the country, the best places to see these giants are along the eastern coastline of India, especially in Bhitarkanika of Odisha, the Sunderbans of West Bengal, and the Andaman and Nicobar Islands. Their distribution of the salties ranges from India to Southeast Asia to Australia and the other islands of Oceania.

Saltwater Crocodile at eye level in Sundarban Tiger Reserve, West Bengal, India. Image credit: Soumyajit Nandy, via Wikimedia Commons

The saltwater crocodiles are well-adapted to live in saltwater environments but are also occasionally found in freshwater habitats when they swim upstream of rivers at coastal deltas. These crocodiles are apex predators and hypercarnivores that feed on almost any other species when the opportunity arises. They kill by ambush and drag their prey into the water, drowning the prey or swallowing the prey alive. These crocodiles have the strongest bites among all animals. These crocodiles also spend less time on land than most other crocodilians. They have been known to spend days in the water migrating long distances. 

The salties also do not shy away from attacking humans as prey, and cases of negative human-saltwater crocodile interactions are quite prevalent. However, even these massive predators are threatened by human activities. Although their wider distribution makes the salties a species labelled as "Least Concern" on the IUCN Red List, they face many threats to survival like killing by humans, illegal trade, poaching for meat and eggs, developmental activities in their habitats leading to destruction of such habitats, etc.

Mugger Crocodile (Crocodylus palustris)

Mugger crocodile at Bhadra Reservoir, Karnataka. Image credit: Kandukuru Nagarjun from Bangalore, India via Wikimedia Commons.

This crocodile species, also called the marsh crocodile, is most widespread in India and is found across freshwater habitats like rivers, lakes, marshes, etc. Globally, the species ranges from southern Iran and east to the Indian subcontinent. The mugger derives its name from the Sanskrit word "makara" and is revered in ancient Indian culture as the vehicle of Hindu deities like Ganga and Varuna. It is also associated with both positive and negative symbolism. 

The mugger is mid-sized, growing up to around 16 feet in length. It also moves on land in search of newer aquatic habitats. Its prey base is quite wide, like that of the saltwater crocodile, as it is the apex predator in the ecosystem where it is found. Unlike the salty, however, the mugger is a threatened species listed as "Vulnerable" on the IUCN Red List. Destruction and degradation of aquatic habitats, water pollution, fishing-related deaths and injuries, revenge killing by humans, poaching and illegal trade, etc., are major factors responsible for declining populations of the muggers. 

Gharial (Gavialis gangeticus)

One of the most threatened of all Crocodilians, the critically endangered gharial, is a rare sight today in India's rivers. It was once found across many river systems in the Indian subcontinent, where it is endemic. Today, this reptile's distribution is quite restricted, and it is found only in India, Nepal, and Bangladesh. It is now extinct in Pakistan and Bhutan. The Chambal River in northern India hosts nearly 80 to 85% of the reptile's global population.

A male gharial. Image credit: Charles J. Sharp via Wikimedia Commons.

The longest among all crocodilians, male gharials grow up to 19 feet, while females grow as long as 14 feet. The snouts of gharials are also much longer and narrower than other crocodilians and come with a set of 110 sharp, interlocking teeth that are ideal for consuming fish. Gharials are thus primarily piscivorous and are unable to prey on larger animals, including humans. An interesting feature of male gharials is the bulbous protrusion at the end of their long snouts, which look like an earthen pot; hence, the name gharials as "ghara" in the local language refers to an earthen pot.

Gharials are very aquatic and do not move too far away from the water bodies they inhabit but bask and nest on the sand banks and sand bars along the water. Muggers move further inland, climbing embankments or rocky slopes. 

An Indian skimmer and a gharial on a sand bar in the Chambal River. Image credit: Rito1987 via Wikimedia Commons.

Gharials went almost extinct by the 2000s when urgent conservation efforts were launched to save the last of the species. Fortunately, captive breeding of gharials worked so that gharials could be released into the wild to restore their populations. Despite the gradual revival in the gharial population, stability has not yet been achieved. A multitude of issues like developmental activities along rivers, sand mining, creation of dams and irrigation canals, pollution, etc., continue to endanger the lives of gharials.

Crocodilians are indicator species. Their population stability indicates that their prey species are present in good numbers, which, in turn, means that the aquatic ecosystems they inhabit are in good condition. We, humans, depend on these aquatic ecosystems for our lives and livelihoods. Hence, the crocodilians show us whether our future is secure or at stake. Conserving them translates to protecting our rivers, lakes, wetlands, and coastal waters and is the need of the day.