Environmental Science Questions and Answers

Answer: A

The State is Tamil Nadu.

Tamil Nadu set up a State-Level Committee for Vulture Conservation, as proposed under the national Action Plan for Vulture Conservation 2020-25, to coordinate the protection of vultures in the state. Vulture numbers in India crashed from the 1990s, mainly because of the veterinary painkiller diclofenac in livestock carcasses.

Sikkim, Assam and Meghalaya are not the state that launched this committee, as the Commission's own remarks on the key confirm.

Answer: A

They were released into Ntangki National Park.

Ten captive-bred Asian giant tortoises (Manouria emys), a critically endangered species, were released into Ntangki National Park in Nagaland's Peren district as part of a conservation programme to restore the species to the north-eastern forests where it once lived.

Periyar (Kerala), Pench (Madhya Pradesh and Maharashtra) and Khangchendzonga (Sikkim) are outside the north-eastern hill forests that are the tortoise's native range in India.

Answer: D

All four are correct: All of the above.

The Ganges river dolphin (Platanista gangetica) is listed as Endangered on the IUCN Red List (1). It lives in murky water and its eyes lack a crystalline lens, so it is practically blind (2), and it navigates and hunts by echolocation, emitting clicks and listening for the echoes (3). It was declared India's National Aquatic Animal in 2009 (4).

Since every statement is true, each narrower option is incomplete.

Answer: A

The region is the Gulf of Mannar Biosphere Reserve.

The Gulf of Mannar, between Tamil Nadu and Sri Lanka, has 21 small islands with coral reefs, seagrass beds, mangroves, estuaries and salt marshes. It is regarded as one of the richest marine biodiversity regions, home to dugongs, sea turtles and thousands of species, and was India's first marine biosphere reserve.

Nanda Devi is a Himalayan mountain reserve, the Sunderbans is a mangrove delta without these 21 islands, and the Nilgiri reserve is in the Western Ghats.

Answer: C

The key gives 40%.

The UN Office on Drugs and Crime published the World Wildlife Crime Report 2024 on 13 May 2024. It draws on government records of seizures from 162 countries and territories between 2015 and 2021, taken from the CITES illegal trade database and UNODC's World WISE database. A secondary summary of the report states that about 40% of the seized animal species were threatened or near threatened on the IUCN Red List, which matches the keyed option.

I could not retrieve the report itself to check the figure against its own tables, and I could not confirm the count of 1,652 species quoted in the question, so this answer rests on the key and that summary. The other options, 30%, 35% and 45%, differ from it only in the figure.

Answer: D

The key gives 9760.

The IUCN Red List groups assessed species into categories, and Critically Endangered (CR) is the highest category of threat for a species still living in the wild: it means the species faces an extremely high risk of extinction. A species qualifies under any one of five sets of criteria, for example a population reduction of at least 80 to 90% over ten years or three generations, fewer than 250 mature individuals with a continuing decline, fewer than 50 mature individuals, or a probability of extinction in the wild of at least 50% within ten years or three generations.

The count of CR species changes with every release of the Red List, which is why the question names version 2023-1 and its date of 11 December 2023. I could not retrieve IUCN's summary statistics table for that release, so I could not check 9760 against it, and no source I could reach contradicts it. The other options, 7762, 8722 and 9251, differ from it only in the figure, so the answer rests on the key and on recall of the table.

Answer: B

Both Statement 1 and Statement 2 are incorrect.

Usable energy does not stay constant up a food chain. By the ten percent law, only about a tenth of the energy at one trophic level is passed on to the next; the rest is used in respiration and lost as heat. That is why food chains are short and pyramids of energy are always upright.

Nor is the energy in an ecosystem constant. Energy flows one way, from the sun through producers and consumers and out as heat, and is not recycled the way nutrients are. An ecosystem therefore needs a continuous input of solar energy to keep running.

Answer: C

The correct matching is A-1, B-3, C-4, D-5.

• Bandli wildlife sanctuary is in Mandi district.
• Daranghati sanctuary is in Shimla district, near Rampur.
• Gamgul Siahbehi sanctuary is in Chamba district, on the border with Jammu and Kashmir.
• Lippa-Asrang sanctuary is in Kinnaur district.

Entry 2, the upper catchments of the Tirthan, Sainj and Jiva rivers, describes the Great Himalayan National Park area in Kullu and fits none of the four, which rules out the options that use it.

Answer: A

From west to east the order is (1), (2), (3), (4).

1. Tropical Andes: South America, about 75° W.
2. Upper Guinean Forests: West Africa, about 5-10° W.
3. Eastern Madagascar (printed 'Medagaskar'): about 48° E.
4. Melanesia (New Caledonia): in the south-west Pacific, about 165° E.

Moving east from the Andes across the Atlantic to West Africa, then to the Indian Ocean and on to the Pacific gives this order. The other options start further east.

Answer: D

The correct statements are (1) and (2) only.

On World Wetlands Day, 2 February 2025, four new sites were added: Sakkarakottai and Therthangal in Tamil Nadu, Khecheopalri in Sikkim and Udhwa Lake in Jharkhand. This brought India's total to 89 Ramsar sites, and Udhwa Lake in Sahibganj district became Jharkhand's first. So statements 1 and 2 are correct.

Statement 3 is wrong because Khecheopalri, a sacred lake in West Sikkim, is in Sikkim, not Tamil Nadu. Because 1 and 2 are both true, and no option lists three statements, the only option that contains both is (1) and (2) only.