Sixteen years after the Deepwater Horizon oil spill harmed large coral areas in the Gulf of Mexico, researchers are creating methods to support recovery of these ecosystems. NOAA Fisheries reports that a recent project used lab-grown corals, advanced diving methods and custom tools to place corals on the deep seafloor. The 2010 rig explosion led to an oil release that affected mesophotic and deep benthic zones with little sunlight. These middle-light ocean areas hold coral communities that support fish and other sea life. Restoration focuses on rebuilding these habitats because work at such depths is harder than in shallow reefs. Scientists learned to gather mesophotic corals and keep them in labs, studying their growth and reproduction to produce new colonies for return to the sea. In 2021, live corals including Swiftia exserta were collected and brought to federal labs where they spawned, aiding study of reproduction and larval stages. By 2026, teams outplanted lab-reared corals during a mission on the NOAA Ship Nancy Foster. Corals such as Swiftia exserta, Muricea pendula and Thesea nivea were placed on concrete domes designed to aid growth and provide shelter for small marine animals. A new device called the coral torpedo allowed precise delivery of specimens to divers at depth, improving on earlier large platforms. Technical divers used closed-circuit rebreathers for extended time underwater at sites hundreds of feet down, with decompression stops and medical oversight on return. The mission outplanted 26 mesophotic corals at about 66 metres and relocated 16 fragments, reaching 72.5 metres while collecting samples and mapping seafloor. This marked the first outplanting of lab-reared mesophotic corals by rebreather divers. Monitoring will continue to assess survival and growth. The effort forms part of the Deepwater Horizon Mesophotic and Deep Benthic Communities Restoration project led by NOAA and the Department of the Interior.
