Danajon Bank
The Danajon Bank is the only double barrier reef in the Philippines, which is a very rare geological formation, which is located in the Camotes Sea. It comprises two sets of large coral reefs that formed offshore on a submarine ridge due to a combination of favorable tidal currents and coral growth in the area. Overview. One of only six double barrier reefs in the world, Danajon Bank runs for 156 kilometers [97 miles] in the Central Visayas, between the following islands: Bohol, Cebu, and Leyte. There are only 3 major passages through this double reef — the NorthWest  Pass, the Middle Pass, & the NorthEast Pass. The Danajon Bank's overall area is 272 square kilometers [105 square miles], with an aggregate coastline of 699 kilometers [434 miles], which includes 40 islands. The Danajon Bank makes up over 1% of the total coral reef area of the Republic of the Philippines, which is estimated at about 27,000 square kilometers [10,424 square miles]. Conservation efforts. Due to overfishing, the Danajon Bank has a declining population of fish, and many upper-level predators have ceased to hunt along the reef. To counteract this, 34 Marine Protected Areas have been established. From  2003 to 2010 USAID funded the FISH Project, a conservation project aimed at managing fisheries in the Philippines, including those on the Danajon Bank. Dynamite fishing is the preferred method of fishing there, and the fish catch has considerably dwindled due to the absence of the fish and the destruction of the various coral reef habitats. Species. Species such as flathead fish, anemonefish, parrotfish, angels, wrasses, blue-edged sole, and messmate pipefish are present in the ecosystem of the Danajon Bank. Large sea fans and sponges live in the areas with deeper water, as does branch coral. The reef is  also home to three endangered coral species such as the mushroom coral, bubble coral, and elegance coral. Seahorses live in the reef, and have become a popular attraction for environmentalists seeking to observe the animal in its natural habitat. It is home to a vast array of commercially valuable reef fishes, shellfish, crustaceans, and invertebrates such as sea cucumbers and sea urchins. Its extensive seagrass beds are nursery and feeding grounds for various species of rabbitfish ("siganid"s) and sea horses, while its mangroves are spawning habitats for crustaceans, shrimps, and various fishes. Almost all sea grasses that occur in the  Republic of the Philippines are well represented in this double barrier reef.