Question map
Which of the following have coral reefs? 1. Andaman and Nicobar Islands 2. Gulf of Kachchh 3. Gulf of Mannar 4. Sunderbans Select the correct answer using the code given below:
Explanation
The correct answer is option A (1, 2 and 3 only).
The four major coral reef areas identified for intensive conservation and management in India are: Gulf of Mannar, Gulf of Kutch, Lakshadweep, and Andaman and Nicobar Islands.[3] Fringing reefs, the most common reef form, are found in Andamans.[4] Patch reefs are seen in the Palk Bay, Gulf of Mann and Gulf of Kachchh.[4] Barrier reefs are seen in Nicobar and Lakshadweep.[4]
The Sunderbans, however, is not mentioned in any of the documents as having coral reefs. The Sunderbans is characterized by mangrove forests[5], which are different ecosystems from coral reefs. Mangroves thrive in muddy, brackish water environments typical of deltaic regions, while coral reefs require clear, shallow, saline waters—conditions not found in the Sunderbans.
Therefore, coral reefs occur in Andaman and Nicobar Islands (1), Gulf of Kachchh (2), and Gulf of Mannar (3), but not in Sunderbans (4).
Sources- [1] Geography of India ,Majid Husain, (McGrawHill 9th ed.) > Chapter 5: Natural Vegetation and National Parks > Mangroves in India-2019 > p. 53
- [2] Geography of India ,Majid Husain, (McGrawHill 9th ed.) > Chapter 5: Natural Vegetation and National Parks > Mangroves in India-2019 > p. 53
- [3] Geography of India ,Majid Husain, (McGrawHill 9th ed.) > Chapter 5: Natural Vegetation and National Parks > Mangroves in India-2019 > p. 53
- [4] Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 4: Aquatic Ecosystem > 4.9.3. Classification and their location > p. 51
- [5] https://faolex.fao.org/docs/pdf/IND170494.pdf
PROVENANCE & STUDY PATTERN
Full viewThis is a foundational 'Geography x Environment' overlap question. It tests a single core concept: the physical conditions required for coral growth (clear, saline water) versus the conditions of a river delta (turbid, fresh water). If you know the Sunderbans is a massive sediment-heavy delta, this question solves itself.
This question can be broken into the following sub-statements. Tap a statement sentence to jump into its detailed analysis.
- Explicitly names fringing reefs as the most common reef form and states they are found in the Andamans.
- Provides a classification of reef types and directly links one type (fringing) to the Andaman group.
- Lists Andaman and Nicobar Islands among the four major coral reef areas identified for conservation and management in India.
- Positions the islands as a nationally recognized coral region, implying significant reef presence.
- States that the main coral reefs of India include the Andaman and Nicobar Islands.
- Notes establishment of the National Coral Reef Research Centre at Port Blair, indicating institutional recognition of reefs there.
- Explicitly names 'Gulf of Katchchh' as a location of patch reefs.
- Places Gulf of Katchchh alongside other known reef areas (Palk Bay, Gulf of Mannar), indicating presence rather than speculation.
- Lists 'Gulf of Kutch' as one of the four major coral reef areas identified for conservation.
- Treats Gulf of Kutch as a principal reef region, implying established reef occurrence.
- States that shallow seas near Gulf of Kachchh are characterised with coral formations.
- Links coastal shallow-sea conditions in the Gulf of Kachchh directly to coral ecosystems.
- Explicitly names patch reefs occurring in the Palk Bay, Gulf of Mannar and Gulf of Kachchh.
- Classifies reef types and cites Gulf of Mannar as a location for patch reefs.
- Identifies Gulf of Mannar as one of four major coral reef areas in India marked for conservation.
- Positions Gulf of Mannar clearly among recognized reef regions (alongside Lakshadweep, Kutch, Andaman & Nicobar).
- Lists Gulf of Mannar among the main coral reef regions of India.
- Treats Gulf of Mannar as part of the core national coral reef extent.
- The passage lists 'mangrove forests' and 'coral reefs' as distinct habitat types in the document.
- The same passage separately names the Sunderbans Tiger Reserve, indicating Sunderbans are presented as a mangrove area rather than a coral-reef area.
- Lists the major coral reef formations in India (Lakshadweep, Andaman & Nicobar, Gulf of Mannar) without mentioning the Sunderbans.
- By omission, indicates coral reefs are associated with other regions rather than the Sunderbans (which are known in the passages as mangrove areas).
States coral reefs occur in shallow, clean, clear, warm tropical waters — a general environmental rule for reef presence.
Compare this rule with basic facts about the Sunderbans (latitude, water temperature, and whether waters are clear/muddy) to judge likelihood of reefs there.
Gives the latitudinal and substrate pattern: reefs mainly between 30°N and 30°S on mud‑free coastlines and restricted to upper ~25–30 m.
Use the Sunderbans' latitude and the fact that it is a muddy delta to assess if conditions (mud‑free coastline, shallow clear water) are met.
Lists Indian reef locations (Andamans, Nicobar, Lakshadweep, Gulf areas) as examples of where reefs do occur in India.
Check whether Sunderbans appears among known Indian reef areas or instead resembles cited reef vs non‑reef regions.
Identifies four major Indian coral reef areas for conservation (Gulf of Mannar, Gulf of Kutch, Lakshadweep, Andaman & Nicobar).
A student can note that major reef zones are specific and see if Sunderbans is included or omitted from authoritative lists.
Explains corals need mud‑free, warm shallow waters and mentions Bay of Bengal island chains (Andaman & Nicobar) as reef locations.
Contrast the Sunderbans' coastal/deltaic, sediment‑laden character with the described mud‑free reef settings to evaluate plausibility.
- [THE VERDICT]: Sitter. Directly covered in Shankar IAS (Ch 4) and NCERT Class IX Geography. If you missed this, your static base is shaky.
- [THE CONCEPTUAL TRIGGER]: Marine Ecosystem Distribution. Specifically, the 'Exclusion Principle'—knowing where ecosystems *cannot* exist is as important as knowing where they do.
- [THE HORIZONTAL EXPANSION]: Memorize the 'Big 4' Reefs: A&N (Fringing), Lakshadweep (Atoll), Gulf of Mannar, Gulf of Kutch. Contrast with 'Minor Reefs' (Netrani, Malvan, Angria Bank). Map the 'No-Go Zones': Mouths of Ganga, Amazon, etc., due to freshwater/silt.
- [THE STRATEGIC METACOGNITION]: Do not memorize lists in isolation. Overlay your 'River System Map' on your 'Coral Map'. Where massive rivers (Ganga-Brahmaputra) meet the sea, turbidity kills corals. This logic eliminates Sunderbans instantly.
References classify reef types and explicitly note fringing reefs occur in the Andamans, linking reef morphology to location.
Classification of reef types is frequently tested in physical geography and environment sections; it connects coastal geomorphology with ecosystem distribution. Master by memorising definitions with example locations (e.g., fringing — Andamans) and practising map-based questions.
- Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 4: Aquatic Ecosystem > 4.9.3. Classification and their location > p. 51
- CONTEMPORARY INDIA-I ,Geography, Class IX . NCERT(Revised ed 2025) > Chapter 2: Physical Features of India > Corals > p. 14
References enumerate the principal Indian reef areas and include Andaman & Nicobar among them.
High-yield for UPSC environment and geography: useful for questions on biodiversity hotspots, conservation priorities and coastal ecology. Learn the standard list (Gulf of Mannar, Gulf of Kutch/Rann of Kachchh, Lakshadweep, Andaman & Nicobar) and their locations/management status.
- Geography of India ,Majid Husain, (McGrawHill 9th ed.) > Chapter 5: Natural Vegetation and National Parks > Mangroves in India-2019 > p. 53
- Environment and Ecology, Majid Hussain (Access publishing 3rd ed.) > Chapter 4: BIODIVERSITY > corAl reefs. > p. 54
Evidence notes Nicobar islands are mainly of coral origin and contrasts overall island origins (Bay of Bengal islands largely tectonic/volcanic vs Arabian Sea islands mainly coral).
Understanding island formation types helps answer physiography and geomorphology questions, and explains associated ecosystems (e.g., coral reefs). Study comparative features of coral, volcanic and tectonic islands and map examples to tackle descriptive and analytical questions.
- Geography of India ,Majid Husain, (McGrawHill 9th ed.) > Chapter 2: Physiography > Islands of the Bay of Bengal > p. 68
- Geography of India ,Majid Husain, (McGrawHill 9th ed.) > Chapter 2: Physiography > THE INDIAN ISLANDS > p. 66
References enumerate principal Indian reef regions and explicitly include Gulf of Kutch/Gulf of Kachchh among them.
High-yield factual knowledge for map-based and short-answer questions; connects to biodiversity, conservation policy and regional geography. Master by memorising the core reef regions and associating them with coastal states and protection efforts.
- Geography of India ,Majid Husain, (McGrawHill 9th ed.) > Chapter 5: Natural Vegetation and National Parks > Mangroves in India-2019 > p. 53
- Environment and Ecology, Majid Hussain (Access publishing 3rd ed.) > Chapter 4: BIODIVERSITY > corAl reefs. > p. 54
Evidence classifies reef types and specifically identifies 'patch reefs' occurring in the Gulf of Kachchh.
Frequently tested concept linking reef morphology to location and processes; helps answer questions on distribution, formation and hazards. Learn definitions, distinguishing features and typical locations for each type.
- Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 4: Aquatic Ecosystem > 4.9.3. Classification and their location > p. 51
- Certificate Physical and Human Geography , GC Leong (Oxford University press 3rd ed.) > Chapter 11: Islands and Coral Reefs > Types of Goral Reef > p. 99
References describe coral preference for shallow, warm, clear, low-sediment waters — conditions noted for seas around Gulf of Kachchh.
Conceptually key for questions on distribution, vulnerability (bleaching, sedimentation) and coastal management. Understand environmental limits and threats to connect physical geography with ecology and policy questions.
- Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 4: Aquatic Ecosystem > 4.9.1. Features > p. 50
- CONTEMPORARY INDIA-I ,Geography, Class IX . NCERT(Revised ed 2025) > Chapter 2: Physical Features of India > Corals > p. 14
- Environment and Ecology, Majid Hussain (Access publishing 3rd ed.) > Chapter 3: MAJOR BIOMES > Classifcation of marine ecosystems > p. 32
The question asks whether Gulf of Mannar has coral reefs; several references list Gulf of Mannar among India’s principal reef areas.
High-yield for UPSC geography: distributions of major reef systems are commonly asked and linked to conservation policy questions. Master the list (Gulf of Mannar, Gulf of Kachchh, Lakshadweep, Andaman & Nicobar) to answer questions on marine biodiversity, protected areas, and coastal management.
- Geography of India ,Majid Husain, (McGrawHill 9th ed.) > Chapter 5: Natural Vegetation and National Parks > Mangroves in India-2019 > p. 53
- Environment and Ecology, Majid Hussain (Access publishing 3rd ed.) > Chapter 4: BIODIVERSITY > corAl reefs. > p. 54
Angria Bank. Since the 'Big 4' locations are now common knowledge, look for 'Angria Bank' (a submerged plateau off Vijaydurg, Maharashtra) or 'Netrani Island' (Karnataka). These are the emerging/minor coral hotspots likely to appear in future options.
The 'Muddy Water' Heuristic. Corals are solar-powered (zooxanthellae need light). The Sunderbans is the world's largest delta, churning out millions of tons of silt. Silt = No Light = No Corals. Eliminate Option 4 (Sunderbans) -> Answer is A.
Disaster Management & Bio-Shields. Link these locations to their protective roles: Mangroves (Sunderbans) buffer against Cyclones/Tsunamis; Coral Reefs (Lakshadweep) prevent coastal erosion. This is a standard Mains GS-3 angle.