Gharial, Gangetic dolphin and olive ridley: the three aquatic species Prelims returns to

Prelims and MainsCurrent affairs on this: Reptiles, amphibians and aquatic species

Three aquatic animals carry most of the questions this theme gets, and each is asked for the same four things: its status on the IUCN Red List, its schedule under the Wildlife (Protection) Act, 1972, where it lives, and the programme built around it. The gharial is the fish eating crocodilian of the northern rivers, Critically Endangered, with the Chambal holding the largest population. The Gangetic dolphin is India's national aquatic animal, Endangered, almost blind and hunting by echolocation in the Ganga and Brahmaputra systems, and the object of Project Dolphin. The olive ridley is the sea turtle that comes ashore in arribadas, mass nestings of thousands of females on the Odisha coast, Vulnerable and protected by a fishing ban and turtle excluder devices. All three are on Schedule I, the Act's highest protection, which is the one fact the three share.

• Gharial (Gavialis gangeticus): long narrow snout, the male's ghara on its tip; Critically Endangered, Schedule I, CITES Appendix I; the National Chambal Sanctuary across Madhya Pradesh, Rajasthan and Uttar Pradesh holds the largest population, with smaller ones on the Girwa (Katarniaghat), Son and Gandak; captive breeding at Kukrail (Lucknow) and Deori (Morena) since Project Crocodile of 1975. The mugger is Vulnerable and the saltwater crocodile of Bhitarkanika Least Concern; both are Schedule I.
• Gangetic dolphin (Platanista gangetica): Endangered, Schedule I, declared the national aquatic animal in 2009; found in the Ganga, Brahmaputra and Meghna systems, with the Vikramshila Gangetic Dolphin Sanctuary at Bhagalpur its only dedicated sanctuary; Project Dolphin was announced on 15 August 2020 and the first national survey, published in 2025, counted 6,327 river dolphins, 6,324 of them Gangetic and three Indus dolphins in the Beas. The Indus dolphin is Endangered and a separate subspecies.
• Olive ridley (Lepidochelys olivacea): Vulnerable, Schedule I, CITES Appendix I; the arribada sites are Gahirmatha, protected as a marine sanctuary since 1997, the Rushikulya mouth and the Devi mouth, with nesting from November to March; the Odisha fishing ban within 20 km of Gahirmatha from November to May, the turtle excluder device on trawl nets and the Coast Guard's Operation Olivia are the protection. India's other sea turtles, the green, hawksbill, leatherback and loggerhead, are all Schedule I; the National Marine Turtle Action Plan of 2021 covers them all.
• What kills them is the same three things: fishing gear, gill nets for the dolphin and gharial and trawls for the turtle; dams and barrages that cut a river into stretches too short for a population; and sand mining and pollution that take the nesting banks and the fish.
• The dugong, Vulnerable and Schedule I, grazes seagrass in the Gulf of Mannar, Palk Bay and the Andamans, and Tamil Nadu notified India's first dugong conservation reserve in Palk Bay in 2022; it is the fourth aquatic animal a question turns to.

Mains: A river species cannot be protected in a sanctuary alone, because a dolphin or a gharial needs the whole river: flow, fish and unbroken stretches, which is why Project Dolphin sits with Namami Gange and why environmental flow norms matter to a species programme.

See also: Himalayan salamander · The Wildlife (Protection) Act, 1972: the schedules · The three lists: IUCN, CITES and the WPA schedules · Namami Gange · Coral reefs of India