Q. Consider the following statements:

1. Hilsa fish is found only in freshwater of rivers in India
2. Saltwater crocodiles are found only in the Sunderbans
3. Gangetic dolphin is found only in Ganges river

Which of the above is / are correct statements?
Answer: None of them
Notes: Hilsa fish is found only in freshwater of rivers in India
This is incorrect statement. The Hilsa fish (also known as ilish) is considered a delicacy in West Bengal and Bangladesh. It is counted amongst the most important and lucrative commercial fish of the Indo-Pacific region. Due to its unique taste and nutritional value, it is considered among the topmost food fishes. It provides direct or indirect livelihood to millions of fishers along the coastal and riverine stretches in its range of distribution. As per the IUCN, Hilsa has witnessed a decreasing trend in India and Bangladesh. The main reasons behind its dwindling population are factors like indiscriminate and over-fishing, pollution and others that have pushed it towards extinction. It is found in brackish, sea and fresh water. It presence signifies health of marine ecosystem.
Saltwater crocodiles are found only in the Sunderbans
This is incorrect statement. The saltwater crocodile is found in the eastern states of Odisha, West Bengal, Andhra Pradesh and Tamil Nadu. The largest specimen was found in Odisha, and reached 7.0 m (23.0 ft). Its population numbers about 300. Saltwater crocodiles live in the mangroves of Bhittarkanika and Sunderbans, Mahanadi Delta, and in the swamplands in Odisha and West Bengal (including rivers).
Gangetic dolphin is found only in Ganges river
This is incorrect statement. Gangetic dolphin is a fresh water mammal living in the rivers Ganga, Brahmaputra and Indus and their larger tributaries. They also live in the deltaic channels of the rivers but do not enter the sea.