Lakshadweep Coral Reefs Decline by Fifty Percent
Why in the News ?
A 24-year-long monitoring study has revealed that coral cover in the Lakshadweep archipelago has declined by nearly 50% since 1998 due to repeated marine heatwaves, worsened by climate change, and reduced recovery after each bleaching event.
Findings of Long-Term Coral Survey:
- Coral decline: Coral cover fell from 37.24% in 1998 to 19.6% in 2022, a nearly 50% reduction.
- Cause: Repeated marine heatwaves triggered by El Niño events (1998, 2010, 2016) are the main reason.
- Recovery lag: Although coral mortality decreased in each event, the rate of recovery also dropped.
- Critical gap: A six-year period without bleaching is needed for coral reefs to recover significantly.
- Predictive value: The study offers a predictive framework to identify vulnerable and recoverable reefs.
Influencing Factors and Local Conditions
- Study locations: Coral health was tracked at Agatti, Kadmat, and Kavaratti atolls.
- Environmental filtering: Wave exposure and depth were found to influence reef resilience.
- Reef response: These local factors determine how reefs respond to climate stress.
- Heatwave frequency: The number of marine heatwave events directly correlates with coral damage.
- Monitoring agency: Study was led by the Nature Conservation Foundation.
| About the Coral Reefs and ENSO Events: Coral bleaching: Caused by loss of symbiotic algae due to heat stress. ENSO impact: El Niño–Southern Oscillation (ENSO) drives ocean warming, leading to bleaching. Biodiversity role: Reefs are hotspots of marine biodiversity and support coastal communities. Recovery timeline: Coral reefs require multiple stable years for regeneration. Conservation need: Highlights urgency for climate mitigation and marine conservation efforts. |