Bleached coral should rattle the whole world
Coral-reef damage in Lakshadweep offers us stark visual evidence—if any is needed—of climate change as a threat. Sadly, we’re nowhere close to bending the carbon-emissions curve
Avisit to Lakshadweep islands off the west coast of India is not complete without a dunk in its waters for a view of its spectacular coral reefs. So goes their reputation as a holiday spot. Snorkellers, however, need to be fore-warned. They now risk emerging with faces made pale by the sight of bleached coral—evidence of colourful clumps of undersea life at risk of being lost forever. As reported, researchers at the ICAR-Central Marine Fisheries Research Institute have found that marine heatwaves since October 2023 have resulted in widespread bleaching of coral reefs in the Lakshadweep Sea. The fourth instance on record till date, this is the most severe. As the world warms up, gigantic clusters of polyp growth elsewhere that once throbbed with marine life have already gone past that stage of stress and turned fully skeletal. To conserve the natural beauty that Lakshadweep hides under its aqua-marine tides, we must choke off carbon fumes. That’s a tall order, but at least what we are witnessing makes it harder to deny that the planet is at threat. The frequency of freaky weather, images of shrunken polar caps and sense of warmer seasons cannot compare with the ecological disaster that we’re watching unfold underwater as proof of climate change.
Since most of the heat that’s trapped by the ‘greenhouse effect’ of our fume-filled atmosphere is absorbed by oceans, marine life faces the brunt of the early stages of global warming. The polyps we find in coral reefs are complex life forms. Most of these live in a deep symbiotic relationship with tiny algae that cling around as nutrient suppliers. The algae’s role involves photosynthesis, for which key microscopic inputs are provided by corals. The dazzling colours that snorkellers love are signals of mutually assured health. While cooperation is the usual state of affairs, excessive heat can disrupt photosynthesis and take this alliance apart, with corals shedding their algae cover in a bid for survival that actually leaves them even worse starved, without nutritional partners. As a coral starves, it turns skeletal, which gives it a ‘bleached’ white look. Coral reefs are sturdy, though. They can recover after long stretches of bleaching if heat conditions reverse and the algae get back into polyp tissue for photosynthesis. Lakshadweep’s heat readings suggest a rising risk of large-scale coral bleaching, with other species that thrive in coral habitats also at threat. While these islands can retain the beauty of their beaches as the mercury gauge worsens, the same cannot be said of their underwater treasures.
Coral-reef degradation finds itself in the news only when there’s an event. The Great Barrier Reef off the coast of Australia, which has been tracked for two decades plus, has recorded four mass-bleaching events in the last seven years, and its algae losses look set to accelerate. On current climate trends, Lakshadweep’s reefs are doomed to share that fate. Beyond letting out sigh-bubbles of despair, there’s nothing that snorkellers faced with heart-break can do about it. With or without goggles, we can see right before our eyes why humanity has been such a malevolent force on the planet. We had hoped to keep the world from getting no warmer than 1.5° Celsius above its pre-industrial average. For that, we’d pledged to bend the curve of carbon emissions. Sadly, there’s no sign so far of that happening. Outright denial is still around, most glaringly in America. Could skeletal evidence under the sea rattle everyone into acting faster?