Corals are marine invertebrates within the class Anthozoa of the phylum Cnidaria. They typically form compact colonies of many identical individual polyps. Coral species include the important reef builders that inhabit tropical oceans and secrete calcium carbonate to form a hard skeleton.
A coral reef is an underwater ecosystem characterized by reef-building corals. Reefs are formed of colonies of coral polyps held together by calcium carbonate. Most coral reefs are built from stony corals, whose polyps cluster in groups.
The Coral Sea is a marginal sea of the South Pacific off the northeast coast of Australia, and classified as an interim Australian bioregion. The Coral Sea extends 2,000 kilometres (1,200 mi) down the Australian northeast coast. Most of it is protected by the French Natural Park of the Coral Sea and the Australian Coral Sea Marine Park. The sea was the location for the Battle of the Coral Sea, a major confrontation during World War II between the navies of the Empire of Japan, and the United States and Australia.
The grey reef shark is a species of requiem shark, in the family Carcharhinidae. One of the most common reef sharks in the Indo-Pacific, it is found as far east as Easter Island and as far west as South Africa. This species is most often seen in shallow water near the drop-offs of coral reefs. It has the typical "reef shark" shape, with a broad, round snout and large eyes. It can be distinguished from similar species by the plain or white-tipped first dorsal fin, the dark tips on the other fins, the broad, black rear margin on the tail fin, and the lack of a ridge between the dorsal fins. Most individuals are less than 1.88 m (6.2 ft) long.
Coral bleaching is the process when corals become white due to various stressors, such as changes in temperature, light, or nutrients. Bleaching occurs when coral polyps expel the zooxanthellae that live inside their tissue, causing the coral to turn white. The zooxanthellae are photosynthetic, and as the water temperature rises, they begin to produce reactive oxygen species. This is toxic to the coral, so the coral expels the zooxanthellae. Since the zooxanthellae produce the majority of coral colouration, the coral tissue becomes transparent, revealing the coral skeleton made of calcium carbonate. Most bleached corals appear bright white, but some are blue, yellow, or pink due to pigment proteins in the coral.
A marine reserve is a type of marine protected area (MPA). An MPA is a section of the ocean where a government has placed limits on human activity. A marine reserve is a marine protected area in which removing or destroying natural or cultural resources is prohibited, marine reserves may also be "no-take MPAs,” which strictly forbid all extractive activities, such as fishing and kelp harvesting.. As of 2007 less than 1% of the world's oceans had been set aside in marine reserves. Benefits include increases in the diversity, density, biomass, body size and reproductive potential of fishery and other species within their boundaries.
The Florida Keys National Marine Sanctuary is a U.S. National Marine Sanctuary in the Florida Keys. It includes the Florida Reef, the only barrier coral reef in North America and the third-largest coral barrier reef in the world. It also has extensive mangrove forest and seagrass fields. The Florida Keys National Marine Sanctuary, designated in 1990, is the ninth national marine sanctuary to be established in a system that comprises 13 sanctuaries and two marine national monuments. The Florida Keys National Marine Sanctuary protects approximately 2,900 square nautical miles of coastal and ocean waters from the estuarine waters of south Florida along the Florida Keys archipelago, encompassing more than 1,700 islands, out to the Dry Tortugas National Park, reaching into the Atlantic Ocean, Florida Bay and the Gulf of Mexico.
Pulley Ridge is a mesophotic coral reef system off the shores of the continental United States. The reef rests on sunken barrier islands and lies 100 miles west of the Tortugas Ecological Reserve and stretches north about 60 miles at depths ranging from 60 to 80 meters. Pulley Ridge was originally discovered in 1950 during a dredging operation conducted by an academic group from Texas. While well known to fishermen, this remarkable habitat remained undiscovered by scientists until 1999 when the U.S. Geological Survey (USGS) and graduate students from the University of South Florida happened upon it. This reef system, like other mesophotic ecosystems, is inhabited by photosynthesizing corals and algae that are adapted to low-light environments. It is habitat for numerous species of bottom fish including Epinephelus morio spawning area.
The Belize Barrier Reef is a series of coral reefs straddling the coast of Belize, roughly 300 metres (980 ft) offshore in the north and 40 kilometres (25 mi) in the south within the country limits. The Belize Barrier Reef is a 300-kilometre (190 mi) long section of the 900-kilometre (560 mi) Mesoamerican Barrier Reef System, which is continuous from Cancún on the north-eastern tip of the Yucatán Peninsula through the Riviera Maya and down to Honduras, making it the second largest coral reef system in the world after the Great Barrier Reef in Australia. It is Belize's top tourist destination, popular for scuba diving and snorkeling and attracting almost half of its 260,000 visitors. It is also vital to the country's fishing industry.
A coral island is a type of island formed from coral detritus and associated organic material. It occurs in tropical and sub-tropical areas, typically as part of a coral reef which has grown to cover a far larger area under the sea.
Elkhorn coral is an important reef-building coral in the Caribbean. The species has a complex structure with many branches which resemble that of elk antlers; hence, the common name. The branching structure creates habitat and shelter for many other reef species. Elkhorn coral is known to grow quickly with an average growth rate of 5 to 10 cm per year. They can reproduce both sexually and asexually, though asexual reproduction is much more common and occurs through a process called fragmentation.
The Coral Triangle (CT) is a roughly triangular area in the tropical waters around the Philippines, Indonesia, Malaysia, Papua New Guinea, the Solomon Islands and Timor-Leste. This area contains at least 500 species of reef-building corals in each ecoregion. The Coral Triangle is located between the Pacific and Indian oceans and encompasses portions of two biogeographic regions: the Indonesian-Philippines Region, and the Far Southwestern Pacific Region. As one of eight major coral reef zones in the world, the Coral Triangle is recognized as a global centre of marine biodiversity and a global priority for conservation. Its biological resources make it a global hotspot of marine biodiversity. Known as the "Amazon of the seas", it covers 5.7 million square kilometres (2,200,000 sq mi) of ocean waters. It contains more than 76% of the world's shallow-water reef-building coral species, 37% of its reef fish species, 50% of its razor clam species, six out of seven of the world's sea turtle species, and the world's largest mangrove forest. In 2014, the Asian Development Bank (ADB) reported that the gross domestic product of the marine ecosystem in the Coral Triangle is roughly $1.2 trillion per year and provides food to over 120 million people. According to the Coral Triangle Knowledge Network, the region annually brings in about $3 billion in foreign exchange income from fisheries exports, and another $3 billion from coastal tourism revenues.
Kadmat Island, also known as Cardamom Island, is a coral island belonging to the Amindivi subgroup of islands of the Lakshadweep archipelago in India. Measuring 9.3 kilometres (5.8 mi) in length, the island has a lagoon with a width of 1.5 kilometres (0.93 mi) covering an area of 25 square kilometres (9.7 sq mi). The ecological feature of the island is of coral reef with seagrass, and marine turtles which nestle here. The Ministry of Environment and Forests (India) has notified the island as a marine protected area for ensuring conservation of the island's animal, plant, or other type of organism, and other resources.
Coral reef protection is the process of modifying human activities to avoid damage to healthy coral reefs and to help damaged reefs recover. The key strategies used in reef protection include defining measurable goals and introducing active management and community involvement to reduce stressors that damage reef health. One management technique is to create Marine Protected Areas (MPAs) that directly limit human activities such as fishing.
Human activities have significant impact on coral reefs. Coral reefs are dying around the world. Damaging activities include coral mining, pollution, overfishing, blast fishing, the digging of canals and access into islands and bays. Other threats include disease, destructive fishing practices and warming oceans. The ocean's role as a carbon dioxide sink, atmospheric changes, ultraviolet light, ocean acidification, viruses, impacts of dust storms carrying agents to far-flung reefs, pollutants, algal blooms are some of the factors that affect coral reefs. Evidently, coral reefs are threatened well beyond coastal areas. Climate change, such as global warming causes coral bleaching which can be fatal to the corals.
Goniastrea retiformis is a species of stony corals in the family Merulinidae. It is native to shallow water in the Indo-Pacific region.
Acropora multiacuta is a species of acroporid coral that was first described by F. Nemenzo in 1967. Found in marine, tropical shallow reefs in lagoons, on rocks or on the tops of reefs, it occurs at depths between 3 and 15 m. It is classed as a vulnerable species on the IUCN Red List, and it has a decreasing population. It is uncommon but found over a large area, including in two regions of Indonesia and the Great Barrier Reef, and is classified under CITES Appendix II.
The poleward migration of coral species refers to the phenomenon brought on by rising sea temperatures, wherein corals are colonising cooler climates in an attempt to circumvent coral bleaching, rising sea levels and ocean acidification. In the age of Anthropocene, the changing global climate has disrupted fundamental natural processes and brought about observable changes in the submarine sphere. Whilst coral reefs are bleaching in tropical areas like the Great Barrier Reef, even more striking, and perhaps more alarming; is the growth of tropical coral species in temperate regions, which has taken place over the past decade. Coral reefs are frequently compared to the "canaries in the coal mine," who were used by miners as an indicator of air quality. In much the same way, "coral reefs are sensitive to environmental changes that could damage other habitats in the future," meaning they will be the first to visually exhibit the true implications of global warming on the natural world.
The Coral reefs of Kiribati consists of 32 atolls and one raised coral island, Banaba, which is an isolated island between Nauru and the Gilbert Islands. The islands of Kiribati are dispersed over 3.5 million km2 (1.4 million sq mi) of the Pacific Ocean and straddle the equator and the 180th meridian, extending into the eastern and western hemispheres, as well as the northern and southern hemispheres. 21 of the 33 islands are inhabited. The groups of islands of Kiribati are:
