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Subject: Biodiversity

1. Ecology & Ecosystems
2. Indian Biodiversity

  • Charaichung Festival at Majuli  

    Why in the News?

    Assam’s Majuli island hosted the second edition of the Charaichung Festival, aimed at reviving Asia’s first protected Royal Bird Sanctuary, Charaichung, established in 1633 AD.

    About Charaichung Sanctuary

    • Established in 1633 AD by Ahom King Swargadeu Pratap Singha (Burha Roja).
    • Considered Asia’s first protected royal bird sanctuary.
    • Holds a 392-year-old legacy.
    • Once thriving, the sanctuary has deteriorated and now requires active conservation.
    • Home to around 150 species of indigenous and migratory birds.

    About the Charaichung Festival

    • Held from December 7 to 10, 2025, at Majuli.
    • Organised by Majuli Sahitya and local communities.
    • Objective:
      • Revive Charaichung sanctuary
      • Strengthen bird conservation
      • Promote Majuli as a global tourism destination
    • Includes a special forest conservation exhibition showcasing biodiversity protection efforts.

    Significance of Majuli

    • Recognised as the world’s largest river island.
    • One of India’s important bird habitats, attracting domestic and international nature enthusiasts.
    • Rich in biodiversity and cultural heritage.
    Which of the following National Parks is unique in being a swamp with floating vegetation that supports a rich biodiversity? (2015)

    (a) Bhitarkanika National Park 

    (b) Keibul Lamjao National Park 

    (c) Keoladeo Ghana National Park 

    (d) Sultanpur National Park

  • Mass Mortality of Goniopora Corals at One Tree Reef  

    Why in the News?

    A new study published in Proceedings of the Royal Society B (December 10, 2025) reports unprecedented coral bleaching and mortality at One Tree Reef (OTR) in the southern Great Barrier Reef, driven by extreme heat and rapid spread of black band disease (BBD).

    Background

    • Coral reefs have shaped Earth’s climate for 250 million years.
    • OTR has not witnessed bleaching of this severity for decades.
    • The impacted species, Goniopora (flowerpot or daisy corals), typically live in lagoons and turbid reefs and are known for thermal tolerance, making their mass mortality alarming.

    Why Black Band Disease Spread at OTR

    • BBD is common in the Caribbean but historically rare in the southern Great Barrier Reef.
    • OTR is offshore and not affected by major nutrient pollution — usually a known trigger.
    • Other coral genera at OTR that bleached did not develop BBD.
    • Northern Great Barrier Reef surveys (2024) showed very low incidence (1–2 percent).
    Consider the following statements: (2018)

    1. Most of the world’s coral reefs are in tropical waters. 

    2. More than one-third of the world’s coral reefs are located in the territories of Australia, Indonesia and Philippines. 

    3. Coral reefs host far more number of animal phyla than those hosted by tropical rainforests. 

    Which of the statements given above is/are correct? 

    (a) 1 and 2 only (b) 3 only (c) 1 and 3 only (d) 1, 2 and 3

  • Sultanpur National Park Sees Surge in Migratory Birds

    Why in the News?

    Sultanpur National Park in Haryana has recorded a sharp rise in migratory bird arrivals, with numbers increasing from 10,000–15,000 in mid-November to an estimated 25,000–35,000 in early December. The rise is linked to falling temperatures, improved wetland conditions and enhanced conservation efforts.

    About Sultanpur National Park

    • Located in Gurugram district, Haryana.
    • Recognized as one of Asia’s major bird habitats.
    • Declared a Ramsar Site in 2021.
    • Ecosystem: freshwater wetland, surrounded by grassland and acacia woodland.
    • Major attraction during winter due to large flocks of migratory birds.

    Migration Patterns

    • Attracts species from: Siberia, Europe, Central Asia and Other northern regions.
    • Migration triggered by:
      • Decreasing temperatures in breeding grounds
      • Availability of food and safe wetland habitats in India.

    Species Currently Sighted

    • Greylag Goose, Bar-headed Goose, Northern Pintail, Common Teal, Shoveler (Northern Shoveler), Common Coot and Black-tailed Godwit (near-threatened).
    Which of the following National Parks is unique in being a swamp with floating vegetation that supports a rich biodiversity? (2015)

    (a) Bhitarkanika National Park 

    (b) Keibul Lamjao National Park 

    (c) Keoladeo Ghana National Park 

    (d) Sultanpur National Park

  • Meghalaya’s New Spider Discoveries

    Why in the News?

    Researchers from the Zoological Survey of India have identified two new species of jumping spiders in Meghalaya, further highlighting the region’s status as a major biodiversity hotspot.

    The new species are:

    • Asemonea dentis
    • Colyttus nongwar

    Their formal descriptions have been published in Zootaxa, an international peer-reviewed journal.

    Location & Significance

    • Found in the forested landscapes of Meghalaya, part of the Indo-Burma biodiversity hotspot.
    • The Northeast is considered one of India’s least-explored yet ecologically rich regions.

    About the Species

    Asemonea dentis

    • Belongs to the genus Asemonea; this is only the third Indian species in this genus.
    • Named for a distinct tooth-like projection on the male palpal femur.
    • Male: greenish-brown body with pale-yellow V-shaped abdominal marking.
    • Female: creamy white body with fine black markings.
    • Genus characteristics: associated with shrubs and foliage; less studied in India.

    Colyttus nongwar

    • Only the second Indian species of the genus Colyttus.
    • Named after Nongwar village in the Khasi Hills.
    • Both sexes display:
      • Oval reddish-brown carapace
      • Light-brown abdomen
      • Creamy anterior band with five chevron-shaped patches
    • Genus: little-known Oriental group with limited representation in India.
    Recently, for the first time in our country, which of the following States has declared a particular butterfly as ‘State Butterfly’? (2016)

    (a) Arunachal Pradesh 

    (b) Himachal Pradesh 

    (c) Karnataka 

    (d) Maharashtra

  • Predation by Horn-Eyed Ghost Crab: New Ecological Observation on India’s East Coast

    Why in the news?

    Researchers from GITAM School of Science, Visakhapatnam, have documented the first confirmed instance of a horn-eyed ghost crab preying on a mottled lightfoot crab at Rushikonda Beach, Andhra Pradesh.
    Published in: Journal of Threatened Taxa (November edition).

    Significance of the Finding

    • Demonstrates unusual predator-prey interaction not recorded earlier in India
    • Indicates behavioural extension of the horn-eyed ghost crab into rocky intertidal zones
    • Suggests flexible foraging strategies in shifting coastal environments

    About Horn-Eyed Ghost Crab

    • Belongs to genus Ocypode and IUCN Red List Status: Least Concern (LC) on the IUCN Red List
    • Keystone species and ecological indicator of coastal health
    • Known for sandy intertidal habitat
    • Roles in ecosystem: Regulates populations of smaller fauna and Burrowing influences sand structure and aeration
    • Known predators of clams, snails, worms, insects, shrimps and even turtle/bird hatchlings
    • India records six ghost crab species; Rushikonda hosts at least three (O. brevicornis, O. macrocera, O. cordimanus)

    With reference to ‘dugong’ a mammal found in India, which of the following statements is/are correct? (2015)

    (1) It is a herbivorous marine animal.

    (2) It is found along the entire coast of India.

    (3) It is given legal protection under Schedule I of the Wildlife (Protection) Act 1972.

    Select the correct answer using the code given below.

    (a) 1 and 2 (b) 2 only (c) 1 and 3 (d) 3 only

  • Humpback Whale Population Recovery

    Why in the News

    The Humpback whale population has seen a major recovery from about 10,000 to nearly 80,000, due to successful conservation measures and their ability to adapt their food sources.

    Humpback Whale 

    • Scientific Name: Megaptera novaeangliae
      Family: Balaenopteridae (Rorqual whales)
      Type: Baleen whale

    Distribution and Migration

    • Found in all major oceans from sub polar waters to equatorial regions
      • Known for long distance migrations: Polar regions in summer for feeding and Tropical/subtropical seas in winter for breeding

    Physical Characteristics

    • A prominent hump in front of the dorsal fin
      • Extra long pectoral fins (inspiration for the name Megaptera meaning big winged)
      Females larger than males

    Feeding and Behaviour

    • Unique feeding strategy: Bubble Net Feeding
    • Whales exhale bubbles while spiraling upward to trap prey
    • Diet: Krill and various schooling fish like anchovies, sardines, mackerel, cod, capelin

    Lifespan and Reproduction

    • Sexual maturity: 4 to 10 years
      • One calf every 2 to 3 years

    Conservation Status

    • IUCN Red List: Least Concern
      • Population recovery highlights the success of global marine conservation policies and sustainable whaling bans
    With reference to ‘dugong’ a mammal found in India, which of the following statements is/are correct? (2015)

    (1) It is a herbivorous marine animal

    (2) It is found along the entire coast of India

    (3) It is given legal protection under Schedule I of the Wildlife (Protection) Act 1972. 

    Select the correct answer using the code given below. 

    (a) 1 and 2 (b) 2 only (c) 1 and 3 (d) 3 only

  • Dudhwa Tiger Reserve and Rainbow Water Snake 

    Why in the News

    A Rainbow Water Snake (Enhydris enhydris) was documented for the first time in Uttar Pradesh with photographic evidence from the buffer zone of Dudhwa Tiger Reserve.

    Dudhwa Tiger Reserve 

    • Location: Indo Nepal border, Lakhimpur Kheri district, Uttar Pradesh
      Established: 1988
      Area: 1,284 sq km
      Constituents:
    • Dudhwa National Park
    • Kishanpur Wildlife Sanctuary
    • Katerniaghat Wildlife Sanctuary
    • Buffer includes North Kheri, South Kheri, and parts of Shahjahanpur forest divisions
    • Habitat Type: Typical Tarai Bhabar ecosystem of Upper Gangetic Plains
      Rivers:
    • Sharda (near Kishanpur)
    • Geruwa (through Katerniaghat)
    • Suheli and Mohana (in Dudhwa NP)
    • All are tributaries of the Ghagra River
    • Vegetation: North Indian Moist Deciduous forests, noted for Sal
      Flora Examples: Sal, Asna, Asidha, Haldu, Faldu, Gahmhar, Kanju

    Rainbow Water Snake 

    • Scientific Name: Enhydris enhydris
      Conservation Status: IUCN: Least Concern
      Nature: Slightly venomous, fish eating freshwater snake
      Distribution: South and Southeast Asia including India, Nepal, Bangladesh, Myanmar, Sri Lanka, Thailand etc.
      Habitat: Marshlands, ponds, rice fields freshwater zones
      Distinctive Features:
    • Up to 130 cm long
    • Two pale stripes along body converging near crown
    • Brown to greenish brown body with pale belly
    In India, if a species of tortoise is declared protected under Schedule I of the Wildlife (Protection) Act, 1972, what does it imply? (2017)

    (a) It enjoys the same level of protection as the tiger

    (b) It no longer exists in the wild, a few individuals are under captive protection; and how it is impossible to prevent its extinction

    (c) It is endemic to a particular region of India. 

    (d) Both (b) and (c) stated above are correct in this context.

  • Saving Rock Eagle Owl Eggs at a Telangana Quarry 

    Why in the News?

    A rare conservation incident unfolded at Yenakathala village, Vikarabad district (Telangana) where operations in a stone quarry were halted for 30+ days to protect five eggs of the endangered Rock Eagle Owl found in a rock crevice. The quarry is incurring ₹1.2 lakh loss per day (₹35 lakh total) to ensure safe hatching. This has been hailed as a “miracle” rescue and an example of community-led wildlife protection.

    About the Rock Eagle Owl (Indian Eagle-Owl) – Bubo bengalensis

    • Also called Bengal Eagle-Owl
    • Large horned owl species
    • Habitat: Hilly scrub forests, cliffs, rock crevices
    • Camouflage: Brown & grey plumage with a white throat patch
    • Distribution: Throughout India
    • IUCN Status: Least Concern globally, but population decreasing
    • In India:
      • Protected under Schedule I, Wildlife Protection Act, 1972
      • This places it at par with species like tigers and elephants in terms of legal protection
    • Threats: 
      • Habitat loss
      • Quarrying and mining
      • Poaching (₹35–40 lakh per bird in black market)
      • Superstitious killings

    Important:

    • Nesting sites are difficult to locate; nests are usually in rock niches and cliffs, not trees.
      The species abandons the nest if touched by humans.
    In India, if a species of tortoise is declared protected under Schedule I of the Wildlife (Protection) Act, 1972, what does it imply ? (2017)

    (a) It enjoys the same level of protection as the tiger. 

    (b) It no longer exists in the wild, a few individuals are under captive protection; and how it is impossible to prevent its extinction. 

    (c) It is endemic to a particular region of India. 

    (d) Both (b) and (c) stated above are correct in this context.

  • Why does India need bioremidiation

    Introduction

    Bioremediation uses microorganisms such as bacteria, fungi, algae, and plants to break down toxic pollutants like pesticides, plastics, heavy metals, and industrial chemicals into harmless by-products. With India experiencing severe air, water, and soil contamination, bioremediation provides a scalable and sustainable pathway to clean ecosystems. At the same time it will  generate opportunities in biotechnology and environmental consulting.

    What Is Driving India Toward Bioremediation?

    1. Rapid industrialisation: Intensifies contamination of air, water, and land, increasing demand for cost-effective clean-up solutions.
    2. High pollution load: Rivers continue to receive sewage and industrial effluents daily, causing persistent ecological and health risks.
    3. Limitations of traditional clean-up: Conventional methods are expensive, energy-intensive, and often shift pollutants to secondary waste streams.
    4. Biological advantage: Indigenous and extremophile microbes adapted to local temperatures, salinity, and soil conditions perform better than imported strains.

    How Do Different Types of Bioremediation Work?

    1. In situ bioremediation: Direct treatment at the contaminated site (e.g., bacteria sprayed on oil spills or contaminated soil treated on location).
    2. Ex situ bioremediation: Removal and controlled treatment of polluted soil or water in bioreactors or treatment facilities before returning it.
    3. Combination with biotechnology: Genetically modified microbes designed to degrade complex pollutants like plastics or toxins offer enhanced efficiency.

    How Is India Using Bioremediation Today?

    1. Government-supported pilot projects: DBT supports several programmes through its Clean Technology Programme, linking universities, research institutions, and industries.
    2. CSIR-National Environmental Engineering Research Institute initiatives: Mandate to develop and implement bioremediation solutions; contributes to policymaking.
    3. Indian Institute of Technology experiments: Development of microbial synthesised compounds to mop up oil spills and identify bacteria suitable for soil restoration.
    4. Emerging startups: Firms like Biotech Consortium India Limited (BCIL) and Ecominr India offer soil and water microbial solutions.

    What Are Other Countries Doing?

    1. Japan: Integrates microbial and plant-based systems into municipal solid waste strategy.
    2. European Union: Funds cross-country projects to remove toxins, clean up oil spills, and restore mining sites.
    3. China: Makes bioremediation a priority under soil pollution control frameworks and uses genetically improved bacteria for industrial waste.

    What Are the Risks and Challenges?

    1. Environmental risks: Introduction of genetically modified organisms must be strictly monitored to prevent unintended ecological effects.
    2. Lack of unified standards: Absence of national bioremediation protocols, biosafety guidelines, certification systems.
    3. Knowledge and skill gaps: Limited trained personnel, weak microbial testing frameworks, and poor site assessment capacity.
    4. Public scepticism: Low awareness about microbes as environmental allies may slow adoption.

    What Should India Do Next?

    1. Standard-development: Develop national protocols for microbial applications and bioremediation safety.
    2. Regional bioremediation hubs: Link universities, startups, and industries for field testing and faster scale-up.
    3. Government integration: Align bioremediation with Namami Gange, Swachh Bharat Mission, and industrial clean-up mandates.
    4. Public engagement: Raise awareness about biological solutions to restore trust in microbial technologies.

    Conclusion

    Bioremediation presents India with a scalable, sustainable, and scientifically grounded pathway to address its massive environmental burdens. While global examples offer templates for success, India must create strong regulatory frameworks, biosafety standards, and capacity-building ecosystems. Integrating microbes with national missions and industrial compliances can transform bioremediation from pilot projects into mainstream environmental governance.

    PYQ Relevance

    [UPSC 2018] What are the impediments in disposing of the huge quantities of discarded solid wastes which are continuously being generated? How do we remove safely the toxic wastes that have been accumulating in our habitable environment?

    Linkage: This PYQ is highly relevant as it falls under GS3 pollution, waste management, and sustainable clean-up. The article links directly by showing how microbial systems overcome traditional waste-disposal barriers and safely break down toxic, accumulated solid waste.

  • Svalbard

     Why in the News?

    • Scientists recently observed an unexpected large gathering of walruses on the remote shores of Svalbard, indicating shifting wildlife behaviour in the Arctic due to changing climatic conditions.

    About Svalbard 

    Location

    • A Norwegian archipelago in the Arctic Ocean.
    • Lies between mainland Norway and the North Pole (about halfway).
    • Northernmost permanent human settlement in the world.

    Discovery & Status

    • Discovered by Willem Barentsz (Dutch explorer) in 1596.
    • Svalbard Treaty (1920) → established Norwegian sovereignty.

    Geography

    • ~60% glacier-covered; marked by mountains, fjords.
    • Surrounding seas:
      • Arctic Ocean, Greenland Sea, Norwegian Sea.
    Consider the following countries: (2014)

    1. Denmark 

    2. Japan 

    3. Russian Federation 

    4. United Kingdom 

    5. United States of America 

    Which of the above are the members of the ‘Arctic Council’? 

    (a) 1, 2 and 3 only (b) 2, 3 and 4 only (c) 1, 4 and 5 only (d) 1, 3 and 5 only