Overview
- The study, published in Science Advances Wednesday, found bleached coral fragments regained symbiotic algae and full color in about seven weeks after sustained physical contact with healthy, genetically identical fragments.
- High-resolution imaging showed the recovery began within days as the corals’ tissues fused and formed a ‘nutrient highway’ that moved photosynthetic algae from the healthy to the bleached fragment.
- Experiments established strict limits: contact was required (three days to start recovery, five days for full recovery), a gap of a few millimeters produced no effect, and pairings of different genets triggered hostile stinging-cell responses that blocked transfer.
- Scientists say the exact contact method is unlikely to be used across whole reefs, so the team is now working on extracting and culturing the beneficial algae to reintroduce them at scale, but practical reef-level tests remain unproven.
- The finding arrives as ocean heat and a strong El Niño drive widespread bleaching, and it changes how scientists view some bleached corals by showing they can be rescued in controlled ways that may inform future restoration and help protect coastal fishing and tourism livelihoods.