Crocodile

Crocodiles are large aquatic reptiles belonging to the Crocodilia order. They are known for their powerful jaws and conical teeth, which are important for them since they are carnivorous animals. The crocodiles that can be found in India include:

• Crocodylus porosus or the Saltwater Crocodile
• Crocodylus palustris or the Marsh Crocodile
• Gavialis gangeticus or the Gharial

And have been marked as least concern, vulnerable and critically endangered according to the IUCN’s Red list.

Physical Characteristics

All species of crocodiles have long snouts which vary in size according to the species. The scales that are on the body are arranged in a regular pattern and have thick, bony plates. Each of the different species is identified by proportions of the snout, arrangement of the snout, and the structure of the dorsal. Among these the Marsh Crocodile is a medium to large species of crocodile with the adult male weighing up to 450 kg with a length of 18 ft. The juveniles of this species are light tan in color with a black cross banding on its body and tail, with the adults generally colored in gray to brown. The marsh crocodiles are sexually dimorphic in nature which means the males tend to be larger in size than the females.

Habitat and Distribution

These reptilian species of crocodiles are found primarily in the Indian subcontinent in the countries of India, Sri Lanka, Pakistan, Nepal, and Bangladesh. In India, marsh crocodiles have been reported from over 15 states and have been estimated to have a wild population of 3,000 to 5,000 adult individuals. Marsh crocodiles are found in freshwater habitats, rivers, lakes, marshes, and irrigation canals and so are mostly seen in the Gangetic region of Bihar and Jharkhand and the region of the Chambal River of Rajasthan, Madhya Pradesh and Gujarat.

Diet and Hunting

Marsh Crocodiles are opportunistic feeders which mean they eat whatever is available to them but mostly prefer fish. The juveniles eat insects and small fish whereas the adults eat fish, snakes, turtles, other reptiles, birds, monkeys, deer, and sometimes even buffalo.

During a hunt, they submerge themselves in water with only their eyes, ears and nostrils above water. The scales on their back are sensitive and act as sensors that detect even the slightest of movement. These scales can detect touch, movement, and temperature changes in the environment. Since the crocodiles can sense the presence of prey through the slightest vibration in water, hunting at night becomes easier.

Reproduction and Lifespan

The crocodiles attain maturity by the age of 8 to 10 years in females and 12 to 15 years in males. The females lay 25 to 30 hard-shelled eggs weighing between 50 to 160 grams which are laid during the annual dry season. The females create a nest at the opening of a burrow where she incubates them for around 55 to 75 days. After hatching, the females remain close to the offspring to protect them from predators for several weeks. The offspring may disperse as they grow, but tend to remain near the nest for over a year.

Marsh crocodiles live 28 years in the wild and up to 31 years in captivity.

Behavior and Social Structure

Marsh crocodiles are mostly nocturnal creatures and are most active after dark. They spend most of their time in water and thermoregulate their bodies by staying in water and shady areas or bask out in the hot sun, as and when required. Dominant animals according to their hierarchy get premium access to desired sites for nesting and soaking in the sun. During a drought or in extreme cold, the crocodiles will dig out burrows near the banks of the river to seek refuge in them. These burrows can be many meters long.

Conservation Efforts

According to the IUCN’s Red list, the marsh crocodiles have been classified as vulnerable due to factors such as loss of habitat because of agricultural and industrial expansion, and urban development which cause the wetlands of these reptiles to deplete. Apart from these, hunting and poaching are also factors that threaten them since they are valued for their thick skin which is used in making leather goods. A reduced prey base is also a factor that threatens them, primarily due to overfishing in the related water bodies, which causes them to move out into human settlements leading to human-animal conflicts.

The Indian Crocodile Conservation Project, 1975 was started with the aim of increasing the near extinct population of the saltwater crocodiles, marsh crocodiles, and the gharial, and has so far been commendable in their work.

The IUCN’s Species Survival Commission’s (IUCN-SSC) Crocodile Special Group is an international organization that includes biologists, wildlife managers, government officials, researchers, NGOs, etc. who are actively involved in conserving the 23 species of alligators, crocodiles, caimons, and gharials across the world.

Amazing Facts about Crocodiles

• The temperature during incubation determines the sex of the offspring that will hatch, for example, if the temperature is cool, around 30 °C, the hatchlings are all female and with warmer temperatures, around 34 °C, hatches are all males.
• Even though its scales seem rough and bony, they are quite sensitive and act as a bonus sensory organ that can detect the slightest movement in the water.

Frequently Asked Questions

 How many types of crocodiles are there in India?

India has three types of crocodiles:

• Saltwater Crocodile
• Marsh Crocodile
• Gharial

Are the Indian crocodiles endangered?

Indian crocodiles such as the saltwater crocodile, marsh crocodile, and the gharial have been marked as least concern, vulnerable and critically endangered according to the IUCN’s Red list respectively.

Do crocodiles only live in water?

Crocodiles are reptiles that spend most of their time in water and thermoregulate their bodies by staying in water and shady areas or bask out in the hot sun, as and when required.

Where can I see marsh crocodiles in India?

The sloth bears can be found in the following protected areas:

• Ranthambore National Park
• Bandhavgarh National Park
• Satpura National Park

What are the main threats to crocodiles?

The main threats to crocodiles are loss of habitat, hunting, poaching and loss of prey base due to overfishing.

Do crocodiles lay their eggs in water?

The female crocodiles lay their eggs in a nest that they create in a burrow and not in water.