Context: Recently, the two-day long census to count the number of marsh crocodiles in Vishwamitri river has concluded and the data is being analysed.
Relevance of the Topic:Prelims: Key facts about crocodile species in India.
About Vishwamitri River
- The Vishwamitri originates from the Pavagadh hills in Panchmahal district, Gujarat.
- Primarily it is a rain-fed river. It flows around 80 kms, merges with Dhadhar river and eventually drains into the Gulf of Khambhat, Arabian Sea.
- The Vadodara-stretch of the Vishwamitri is home to a large population of mugger or marsh crocodiles.
- The river is highly polluted as it receives a large amount of sewage and industrial pollutants.
Crocodiles in India
- India is home to three crocodile species – Gharial, Mugger, and Saltwater Crocodiles.
- Usually spotted on banks of the aquatic systems, crocodiles are cold-blooded animals.
- Crocodiles are apex predators. These reptiles play a critical role in the ecosystem by maintaining biodiversity and ecological balance: they control the population of other aquatic animals.
- India launched the Crocodile Conservation Project in Odisha's Bhitarkanika National Park in 1975, with the aid from the United Nations Development Programme.
- All three crocodile species in India are placed under the Schedule I of the Wildlife Protection Act, 1972.
1. Mugger:
- They have a broad-snouted nose.
- They are also known as Marsh crocodiles. They are found in freshwaters like rivers and also in estuaries and marshy areas.
- Mugger has a diverse and broad diet. They are known to dig burrows or holes for nesting purposes.
- Muggers have stronger legs which allow them to bask mainly on river banks choosing steeper slopes and elevated platforms.
- Their tough keratin scales are known to be sensitive to even the slightest motion in the water and this helps them detect prey easily.
- IUCN status: Vulnerable
2. Gharials:
- They are endemic to the Indian subcontinent.
- They are shy-natured and the most aquatic of all the species.
- They are the longest living crocodile species, native to northern India and are distinguished by their long, narrow snouts.
- The gharials are predominantly a fish-eater.
- Gharials prefer to bask on mid-river sand islands on gentle slopes as they have weaker legs and can only crawl.
- Chambal River (tributary of river Yamuna) holds the largest population of Gharials in the wild.
- IUCN status: Critically Endangered
| Note: Both the species are freshwater and have overlapping habitats in the northern rivers (Ganges, Chambal, Son, Ramganga and Girwa) and eastern (Mahanadi) river systems of India. They have shown systematic resource partitioning in their aquatic environments. |
3. Saltwater crocodiles:
- Largest crocodile species, also recognised as man eater. Largest reptile in the world.
- Also known as estuarine crocodiles. Its habitat includes regions such as Odisha’s Bhitarkanika National Park, West Bengal’s Sundarbans, and the Andaman and Nicobar Islands.
- IUCN status: Least concern.