https://phys.org/news/2018-06-underwater-world-belize-reef.html

Second in size only to the Great Barrier Reef in Australia, the Caribbean reef was named to the prestigious World Heritage List in 1996, but placed on endangered status in 2009 because of Belize's plans to allow oil exploration nearby and the general lack of laws to protect the site.

The warning also encompassed the mangroves that help protect the reef and serve as a breeding ground for many of the hundreds of fish species that inhabit the area.