The increase in ocean temperature due to climate change, changes in water chemistry – increased acidification – and infectious diseases are the main causes of the deterioration of coral reefs. All these factors together or separately cause the death of the polyps or corals that build and inhabit the calcium carbonate structures characteristic of these rich marine ecosystems, abundant in the Indian and Pacific oceans. Under adverse conditions, zooxanthellae, a type of algae that live in symbiosis with the so-called photosynthetic coral polyps, break their relationship with these organisms – or die – and trigger the so-called bleaching of the corals, which progressively pale to death. For a few years, scientists in different parts of the world have been studying how to recover the reefs affected by this process.
The most efficient method to date resembles restocking on dry land ; Experts raise polyps or anthozoans in pools set up for this purpose or in oceanariums and then house them in intact calcareous structures. Unlike in plants, a seed cannot be germinated here; Small pieces of healthy animals have to be cut to adhere by means of plastic belts to cement blocks installed at the bottom or to thick vertical ropes where they regenerate.
The process can be done in situ, where the colonies will live, or in specific environments for their growth before transporting them . Coral farms are located in shallow areas with a marine current, so that the water provides them with the nutrients they need to develop. You have to wait a few months until the specimens grow to be able to move them. They are normally transported in plastic containers, with a pump that oxygenates the water so that organisms are not stressed during the journey. Once transplanted, experts do regular follow-ups and evaluations to make sure they adapt well to the environment. Typically, a metal or plastic plate is installed at the base of the calcareous structure to identify the new corals and monitor their condition and size for a year.
