How Can Studying Mucus Protect Coral Reefs

Corals are an association between animals and plants that deposit a skeleton and build reefs. Coral reefs are now in danger because the marine environment around them is degrading, causing corals to get ill more often. Scientists have used fragments of healthy coral colonies or planted baby corals to help restore reefs that are in bad shape. But for these efforts to succeed, it is vital for the scientists to select healthy corals for planting. Corals use a substance called melanin to trap bacteria that grows in their tissues. We discovered that the enzyme phenoloxidase, which is responsible for making melanin, can be found in the snotty covering of corals, called mucus. We can take samples of this mucus to measure phenoloxidase without harming the corals. By doing so, we can detect whether a coral colony is responding to the presence of harmful bacteria even before it shows any signs of illness.