Researchers have released India’s first open-access, crowdsourced ecoacoustic biodiversity dataset, capturing 518 species across 5,815 minutes of recordings from 25 states and union territories.
What is ecoacoustics?
Ecoacoustics is the study of sounds produced by organisms and the surrounding environment to understand ecosystems, biodiversity and ecological change.
Instead of relying only on visual surveys, passive acoustic recorders can continuously capture:
Bird calls, Insect sounds, Frog and bat calls, Reptile and mammal vocalisations, Marine animal sounds, Background environmental sounds such as rain, wind and human activity
Why does it matter?
Non-invasive monitoring: Sound-based surveys track biodiversity cheaply and continuously across large areas.
Open science: An open-access, crowdsourced dataset lets any researcher reuse the data for conservation.
Baseline data: It creates a reference against which future biodiversity loss can be measured.
[2023] Which of the following organisms perform waggle dance for others of their kin to indicate the direction and the distance to a source of their food?
The Bombay Natural History Society (BNHS) has launched India’s first community-driven removal programme for the invasive suckermouth catfish in Ujani Reservoir, Maharashtra.
Suckermouth Catfish: Key Facts
Origin: Amazon River basin, South America.
Entry into India: Introduced through the aquarium trade and later released into natural waterways.
Local name: “Helicopter fish”.
Why invasive?
Feeds on fish eggs.
Competes with native bottom-feeding fish.
Burrows into riverbanks and can weaken earthen structures.
Adapts to adverse conditions.
Scale of the Invasion
Around 97% of fish in Ujani are alien species including suckermouth catfish, Tilapia and African catfish.
Native fish account for only 3%.
Suckermouth catfish alone constitute around 30 to 40% of the total fish population.
Impact on Fishermen
Around 20,000 people including fishermen, traders, transporters and labourers depend on the reservoir.
Invasive fish damage fishing nets and reduce the catch of economically valuable Rohu, Catla and Mrigal.
Fishermen may need to replace nets every 15 to 20 days, adding to costs.
BNHS Removal Model
Collection centre established at Bhigwan fish market.
Fishermen receive financial incentives for collecting the invasive fish.
36+ tonnes have already been removed.
Fish is processed into molasses used as fertiliser.
Creates a removal + livelihood + waste-utilisation model.
“[2023] Invasive Species Specialist Group (that develops Global Invasive Species Database) belongs to which one of the following organizations?
(a) The International Union for Conservation of Nature
(b) The United Nations Environment Programme
(c) The United Nations World Commission for Environment and Development
The Zoological Survey of India (ZSI) has published the Catalogue of Lepidoptera (Butterflies & Moths) of India in the peer-reviewed journal Zootaxa. The catalogue, prepared over nearly 12 years, provides an updated national inventory of India’s butterfly and moth diversity.
Key Findings
India has 13,703 species of Lepidoptera.
This represents about 8.25% of the world’s known Lepidoptera.
Butterflies: 1,417 species
Moths: 12,286 species
These are distributed across: 3,705 genera, 240 subfamilies, 102 families, 31 superfamilies
Geometroidea
2,205 species of Geometroidea have been catalogued in India.
They belong to: 479 genera, 13 subfamilies, and 4 families
They constitute around 8.8% of the world’s known Geometroidea.
Many are nocturnal pollinators, complementing daytime pollinators such as butterflies.
Note: Geometridae is a very large family of slender-bodied, broad-winged moths.
The Phoenix Species Project, led by Re:wild and the Bezos Earth Fund with the IUCN Species Survival Commission, has launched a $200 million global initiative to recover 100 of the world’s most threatened species.
What is the Phoenix Species Project?
Target: 100 species classified as Critically Endangered (CR) or Extinct in the Wild (EW) on the IUCN Red List.
Geographical spread: 30 countries.
Species covered: Mammals, birds, reptiles, amphibians, fish, invertebrates and plants.
Funding: $200 million
$100 million from Bezos Earth Fund
$100 million from Re:wild and supporting foundations.
Approach: Long-term, locally led species recovery rather than short-term conservation grants.
Important species under the project
Bowmouth guitarfish: Threatened by the shark-fin trade; found in shallow waters from South Africa to Japan and Australia.
Hickory Nut Gorge green salamander: Restricted to a small canyon in North Carolina.
Charco Azul pupfish: Extinct in the wild; freshwater habitat was lost due to drought and water extraction.
Night parrot: Rare, nocturnal ground-dwelling bird of Australia’s arid regions.
India has achieved nearly 20% ethanol blending (E20) in petrol by 2025, making it one of the world’s largest biofuel programmes. As the blending target is achieved, attention is shifting from quantity to the programme’s water use, life cycle emissions and energy efficiency.
What is the E20 Ethanol Blending Programme?
Definition: E20 is petrol blended with 20% ethanol.
Progress: Ethanol blending increased from about 1.5% in 2013-14 to nearly 20% in 2025, with annual consumption of around 700 crore litres.
Benefits: Reduces crude oil imports, boosts farmers’ income and strengthens energy security. Ethanol is often described as a low-carbon fuel because sugarcane absorbs atmospheric carbon dioxide during growth.
What is Energy Return on Energy Invested (EROEI)?
Definition: EROEI measures the usable energy obtained from a fuel relative to the energy spent producing it.
Sugarcane Ethanol: EROEI of about 2 to 4 due to efficient bagasse based distilleries.
Grain Ethanol: EROEI ranges from 1.2 to 2 because of higher fossil fuel inputs.
Significance: Higher EROEI indicates a more energy efficient fuel.
Why is water the biggest concern?
High Water Demand: Estimates by the Commission for Agricultural Costs and Prices and NITI Aayog suggest that sugarcane requires 1,500 to 2,500 mm of water during cultivation.
Large Water Footprint: Producing one litre of sugarcane ethanol may consume 2,000 to 3,500 litres of water.
Groundwater Stress: Major sugarcane growing states already face groundwater depletion.
Resource Trade-off: Excessive ethanol production may replace oil dependence with freshwater dependence.
Distorting Subsidies: Subsidised electricity and fertilisers encourage over extraction of groundwater and excessive fertiliser use. Subsidised urea promotes overuse of nitrogen fertilisers.
What are the other challenges?
Lower Energy Density: Ethanol contains about 21 MJ/litre, compared to 32 MJ/litre for petrol, reducing fuel efficiency by about 6 to 7% under E20 blends. However, ethanol has a much higher octane rating, allowing engines specifically calibrated for higher ethanol blends to achieve more efficient combustion and partially offset this disadvantage. The overall outcome depends on engine design rather than fuel properties alone.
Life Cycle Emissions: Sugarcane ethanol can reduce emissions by 50 to 70%, while grain ethanol offers 20 to 50% reduction, depending on production methods.
Vehicle Compatibility: E20 can corrode certain engine components in older vehicles. Vehicles manufactured from April 2023 onwards are required to be E20 compatible.
Conclusion
India’s ethanol programme represents an important step towards greater energy security, but its long-term success will depend on aligning environmental objectives with sound economics. A resilient biofuel strategy must be guided by transparent life-cycle carbon accounting, rigorous assessment of water use, technology-neutral incentives and market signals that reflect the true value of natural resources.
PYQ Relevance
[2020] According to India’s National Policy on Biofuels, which of the following can be used as raw materials for the production of biofuels? 1. Cassava
2. Damaged wheat grains
3. Groundnut seeds
4. Horse gram
5. Rotten potatoes
6. Sugar beet Select the correct answer using the code given below: (a) 1, 2, 5 and 6 only (b) 1, 3, 4 and 6 only (c) 2, 3, 4 and 5 only (d) 1, 2, 3, 4, 5 and 6
The Supreme Court has clarified that its earlier direction restricting mining within a 10 km radius of the Asan Wetland Conservation Reserve now applies to all Wetland Conservation Reserves across India. Mining in such areas will require prior approval from the competent authority.
What did the Supreme Court clarify?
Nationwide Application: The 10 km mining safeguard around the Asan Wetland Conservation Reserve will now apply to all Wetland Conservation Reserves.
Uniform Principle: The Court held that the protection should apply uniformly across the country.
Case Background: The clarification came while hearing an application filed by the Himachal Pradesh Government.
State’s Argument: Himachal Pradesh contended that Wetland Conservation Reserves do not have a statutory buffer zone unlike national parks.
Further Direction: The Court asked the National Board for Wildlife (NBWL) or the Ministry of Environment, Forest and Climate Change (MoEFCC) to examine whether the Asan Wetland extends into Himachal Pradesh.
What is the Asan Wetland Conservation Reserve?
Location: Situated at the confluence of the Asan and Yamuna rivers in Uttarakhand.
Ramsar Status: Declared a Ramsar Site in 2020.
Ecological Importance: Supports migratory waterbirds and rich aquatic biodiversity.
Judicial Protection: Mining within a 10 km radius requires prior clearance from the NBWL or MoEFCC.
What are Ramsar Sites?
Definition: Wetlands designated under the Ramsar Convention on Wetlands (1971) for their international ecological importance.
India’s Membership: India became a party to the Convention in 1982.
Current Status: India has 101 Ramsar Sites, the highest in Asia.
Significance: Ramsar designation commits countries to maintain the ecological character of wetlands but does not itself create a separate statutory protection regime.
What is the legal position on mining near wetlands?
No Statutory Buffer: The Ramsar Convention and the Wetlands (Conservation and Management) Rules, 2017 do not prescribe a fixed buffer zone around wetlands.
2010 Rules: Earlier rules listed prohibited activities and required prior approval for activities within the wetland’s zone of influence.
2017 Rules: Replaced the earlier framework with a decentralised system led by State Wetland Authorities.
Judicial Safeguard: The Supreme Court’s ruling fills this regulatory gap by requiring prior clearance for mining near Wetland Conservation Reserves.
[2022] Consider the following pairs: Wetland/Lake — Location 1. Hokera Wetland — Punjab 2. Renuka Wetland — Himachal Pradesh 3. Rudrasagar Lake — Tripura 4. Sasthamkotta Lake — Tamil Nadu How many pairs given above are correctly matched? (a) Only one pair
Glaw Lake has been designated as Arunachal Pradesh’s first Ramsar Site, making it the state’s first Wetland of International Importance under the Ramsar Convention.
What is the Ramsar Convention?
International treaty: An intergovernmental treaty for the conservation and wise use of wetlands.
Adopted:2 February 1971 at Ramsar, Iran.
Came into force:1975.
Objective: Promote the conservation and sustainable use of wetlands through national action and international cooperation.
India: A Contracting Party to the Convention.
What is a Ramsar Site?
A wetland designated under the Ramsar Convention for its international ecological importance.
Selected based on criteria such as:
Unique wetland ecosystems.
Biodiversity significance.
Habitat for threatened species.
Importance for migratory waterbirds.
Why is Glaw Lake Significant?
Location: Arunachal Pradesh.
First Ramsar Site: It is the first Wetland of International Importance from the state.
Recognition: Enhances conservation of the Eastern Himalayan wetland ecosystem.
Implementation: Designated under the Ramsar Convention with the involvement of the Ministry of Environment, Forest and Climate Change (MoEFCC) and the Wetlands Division.
[2019] With reference to Wetlands, consider the following statements: 1. Under Ramsar Convention, it is mandatory on the part of the Government of India to protect and conserve all the wetlands in the territory of India. 2. They are covered with hydric soils. 3. Wetlands are often referred to as Kidneys of the Earth. Which of the statements given above is/are correct?
The Asiatic lion population has recovered strongly but is increasingly living outside protected areas. The tension is between a conservation success in numbers and the rising conflict and risk that dispersal brings.
What is the Asiatic lion?
Endemic species: The Asiatic lion (Panthera leo persica) survives only in and around the Gir landscape of Gujarat.
Status change: The International Union for Conservation of Nature (IUCN) moved it from Critically Endangered to Endangered.
Single population: The entire wild population is concentrated in one region, making it vulnerable to a single event.
How has the population and range changed?
Recovery: Numbers grew from about 100 to 150 six decades ago to over 1,000 today.
Dispersal: Nearly half the lions now live outside protected areas.
Satellite groups: For the first time, data shows that more than half—497 lions—now live outside the core Gir protected areas in nine distinct satellite populations spread across 11 districts, spanning a territory of 35,000 square kilometers.
Why does the spread create new risks?
Habitat threat: A proposed limestone mine in the Babarkot corridor threatens a dispersal route.
Disease risk: Past outbreaks of Canine Distemper Virus and babesiosis killed many lions.
Green Status: The species remains assessed as “largely depleted” despite the numeric recovery.
Back2Basics: Asiatic Lion (Gir)
IUCN status: Endangered.
Legal protection: Listed in Schedule I of the Wild Life (Protection) Act, 1972.
Habitat: Gir National Park and Wildlife Sanctuary and surrounding landscape in Gujarat.
Significance:Gir is the only natural home of the wild Asiatic lion.
“[2024] Consider the following statements: 1. Lions do not have a particular breeding season. 2. Unlike most other big cats, cheetahs do not roar. 3. Unlike male lions, male leopards do not proclaim their territory by scent marking. Which of the statements given above are correct? (a) 1 and 2 only (b) 2 and 3 only (c) 1 and 3 only (d) 1, 2 and 3
A study in the journal Geophysical Research Letters reports evidence that global warming is accelerating, not merely continuing. After removing natural noise from five temperature datasets, the authors find the last decade warmed faster than any previous decade on record, and project the 1.5 degree Celsius threshold being breached by 2030.
What is the 1.5 degree Celsius threshold?
Paris target: Under the Paris Agreement, 2015, countries agreed to hold warming well below 2 degrees Celsius above pre industrial levels and to pursue efforts to limit it to 1.5 degrees Celsius.
Why 1.5 matters: Beyond 1.5 degrees Celsius, risks of extreme heat, sea level rise, and ecosystem collapse rise sharply, making it the central guardrail of climate policy.
What are aerosols and the masking effect?
Aerosols: Aerosols are tiny particles from sources such as burning fossil fuels that reflect sunlight and exert a cooling effect on the atmosphere.
How cooling works: Light-colored particles bounce sunlight back into space and help make clouds brighter, which lowers temperatures.
The cooling mask: This pollution has acted like an invisible shield, hiding a portion of the total heat trapped by greenhouse gases
Unmasking: As pollution controls cut aerosols, their cooling effect fades and the full warming from greenhouse gases is felt, an effect the study describes as a disappearing cooling mask.
Why is measuring acceleration difficult?
Noisy temperatures: Global temperatures fluctuate year to year because of natural factors like volcanic eruptions and changes in solar activity. (Volcano noise includes the seismic vibrations, audible sounds, and infrasound produced by subsurface magma movement, degassing, and eruptions. Solar noise refers to intense bursts of radio waves and energetic emissions naturally broadcast by the Sun.)
Masked trend: These events can temporarily hide the underlying human caused warming, making it hard to prove the rate itself is rising.
How did the study establish acceleration?
Multiple datasets: The authors analysed five major global temperature datasets to avoid relying on any single record.
Statistical subtraction: They used statistical methods to remove the influence of volcanic and solar noise, isolating the human driven trend.
High confidence: After removing the noise, they were more than 98% certain the jump in warming rate was real rather than a short lived fluctuation, dating the change to around 2015.
Timing: This change or acceleration in the rate of warming was identified to have begun around 2015 .
Why does the faster pace matter?
Shrinking timeline: Under the earlier, slower rate, the world expected more time before breaching 1.5 degrees Celsius, and the accelerated pace brings the breach forward to 2030.
Twin drivers: Greenhouse gas emissions remain the primary cause, while falling aerosol pollution adds to the acceleration.
What are the challenges to limiting warming to 1.5 degrees Celsius?
Continued emissions growth: Global carbon dioxide emissions remain near record highs, driven by fossil fuel use in power, industry, and transport.
Aerosol paradox: Cutting air pollution saves lives but removes a cooling effect, accelerating near term warming.
Shrinking carbon budget: The remaining budget consistent with 1.5 degrees Celsius is small and shrinks with every year of high emissions.
Slow energy transition: Renewable growth has not yet displaced fossil fuels fast enough to cut absolute emissions.
Feedback loops: Melting ice, thawing permafrost, and forest loss release additional carbon and reduce reflectivity, reinforcing warming.
Finance and equity gaps: Developing countries lack the finance and technology transfer needed to decarbonise while meeting development needs.
Conclusion
The study reframes the problem from steady warming to an accelerating one, advancing the likely 1.5 degree Celsius breach to 2030. The central unresolved issue is that cleaning the air removes a cooling shield, so only deep and sustained cuts in greenhouse gases can slow the pace.
Back2Basics:
Paris Agreement
Adopted: 2015 at the 21st Conference of the Parties (COP21), entering into force in 2016.
Convening body: United Nations Framework Convention on Climate Change (UNFCCC).
Core goal: Limit warming well below 2 degrees Celsius, pursuing 1.5 degrees Celsius above pre industrial levels.
Mechanism: Nationally Determined Contributions, updated every five years, with a global stocktake to assess collective progress.
PYQ Relevance
[UPSC 2022] Discuss global warming and mention its effects on the global climate. Explain the control measures to bring down the level of greenhouse gases which cause global warming, in the light of the Kyoto Protocol, 1997.
Linkage: The question examines the causes, impacts and mitigation of global warming through international climate frameworks. The article adds recent evidence that global warming is accelerating, highlighting the need for faster emission cuts to achieve Paris Agreement goals.
The Standing Committee of the National Board for Wildlife (NBWL) recommended wildlife clearance for the 1,800 MW Panari Pumped Storage Hydropower Project in the Panna-Ranipur Tiger Corridor, despite concerns that it could fragment a critical wildlife corridor.
How does a Pumped Storage Hydropower Project (PSH) work?
Uses two reservoirs at different elevations.
During low electricity demand, water is pumped to the upper reservoir.
During peak demand, water is released to generate electricity.
Acts as a grid-scale energy storage system for renewable energy.
What is the Panna-Ranipur Tiger Corridor?
Connects Panna Tiger Reserve (Madhya Pradesh) with Ranipur Tiger Reserve (Uttar Pradesh).
Facilitates movement of tigers, leopards, and sloth bears.
Ensures genetic exchange and healthy wildlife populations.
A wildlife corridor is a natural passage connecting fragmented habitats, enabling movement, migration, breeding, and genetic exchange among wildlife populations.
Why was the Project Cleared?
NBWL Standing Committee approved it based on recommendations of:
Loss of habitat connectivity and genetic diversity.
Cumulative impacts of multiple infrastructure projects.
Mitigation Measures
Construction of three 30-metre-wide wildlife overpasses.
Relocation of muck dumping and project facilities outside the corridor.
Realignment of project infrastructure to reduce habitat disturbance.
Back2Basics: Panna Tiger Reserve
Designation: Tiger reserve and UNESCO Biosphere Reserve, in Madhya Pradesh.
Location: Panna and Chhatarpur districts, on the Vindhyan ranges along the Ken River.
Distinction: Site of a successful tiger reintroduction after its tiger population was lost around 2009.
Linked project: Adjoins the Ken Betwa river linking project, India’s first interlinking of rivers.
“[2020] Among the following Tiger Reserves, which one has the largest area under ‘Critical Tiger Habitat’? (a) Corbett (b) Ranthambore (c) Nagarjunsagar-Srisailam (d) Sunderbans
