17 stunning underwater photos that will take you on a virtual diving tour this World Oceans Day

Coral reefs in the Philippines are the second largest in Southeast Asia, and 98% of Philippine reefs are deemed to be at risk.

According to World Wildlife, "Whale sharks are highly valued on international markets. Demand for their meat, fins and oil remains a threat to the species, particularly by unregulated fisheries. They are victims of bycatch, the accidental capture of non-target species in fishing gear. And whale shark tourism presents a threat to the species as it can interrupt their feeding and sharks can be injured by boat propellers."

According to National Geographic, "The leaping and spinning likely serve several purposes, including the removal of irksome remoras, fish that latch on to eat parasites."

But biologists also believe the jumping and spinning is used for communication. Different moves might signal "Let's go" or "I find you attractive," according to National Geographic.

According to Live Science, "The pair forms a symbiotic relationship. The anemone provides protection and leftovers for the clownfish, while the clownfish brings food to the anemone and preens its host, removing parasites."

According to Oceana, "Barracudas are naturally inquisitive. Because they hunt mainly by sight, barracudas sometimes attempt to steal fish from spear fishers or approach divers, mistaking the glint of a diving knife as a shiny fish. Despite this behavior, barracudas rarely attack humans unprovoked."

Shoals and schools of fish are two different things. According to Jstor Daily, "A shoal is a looser group, sometimes consisting of different species that hang out together (often temporarily) but are not organized. Schools are highly structured with coordinated movements and a common direction."

The seven sea turtle species are leatherback, loggerhead, green turtle, flatback, hawksbill, Kemp's ridley, and olive ridley.

They are currently listed as a vulnerable species.

The lagoon is home to dozens of Japanese and American ships and aircraft that sank during World War II.

However, they are now an invasive species of fish in the Atlantic Ocean. According to Ocean Service, "Scientists fear that lionfish will kill off helpful species such as algae-eating parrotfish, allowing seaweed to overtake the reefs."

According to Oceana, "The lemon shark is targeted by commercial and recreational fisheries throughout its range and is listed as Near Threatened by the IUCN Red List. The shark's fins and meat are highly sought after to be sold on international markets. The thickness of the lemon shark's skin also makes it ideal for the production of leather."

According to National Geographic, "They spend the majority of their time inactive, partially buried in sand, often moving only with the sway of the tide."

According to National Geographic, "There are some 2,000 species of sea star living in all the world's oceans, from tropical habitats to the cold seafloor. The five-arm varieties are the most common, hence their name, but species with 10, 20, and even 40 arms exist."

Mandarin fish grow to just 6 centimeters in length. Rather than scales, they are coated in mucus.

While octopuses are not believed to be under threat, they are sensitive to pollutants, according to the National Wildlife Federation.

Though reefs around the world have suffered bleaching due to rising ocean temperatures, those in the Red Sea have managed to survive. Scientists are currently studying these reefs in hopes that it can help save those dying due to climate change.

Tiger sharks are found worldwide and are listed as near threatened.

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