The lophelia coral is a true stony coral that lives in the deep sea rather than on shallow, tropical coral reefs. Like all corals, this species is closely related to anemones, jellyfishes, and other animals in the Phylum Cnidaria. Unlike shallow-water corals, lophelia corals and other deep-water corals do not get their food from symbiotic algae living inside their cells. Instead, they are filter feeders and obtain all of their energy by picking individual plankton from the water that flows along deep-sea currents.
Wherever it lives, the lophelia coral builds structure that provides habitat for many kinds of invertebrates and fishes. Some lophelia coral reefs can be enormous, stretching for several miles and rising to at least 100 feet (30 m) above the seafloor. Lophelia coral reefs of this size may be tens of thousands of years old. Individual living lophelia colonies are extremely slow growing and are known to live for more than 1000 years. This species is commonly found down to depths of approximately 3300 feet (1000 m), but it has been observed or collected from depths of nearly 10,000 feet (3000 m).
Like all stony corals, the lophelia coral builds a skeleton of calcium carbonate – a compound that will become increasingly more rare as the ocean acidifies (a phenomenon caused by the ocean’s absorption of acidic carbon dioxide from the atmosphere). As deep waters are naturally more acidic than shallow waters, deep-water corals are particularly vulnerable to this problem. Unless people cut carbon dioxide emissions, scientists predict the waters in which deep-water corals live may eventually become acidic enough to literally dissolve their skeletons. Acidification not only risks the survival of this and other corals but also the high numbers of other species that rely on coral reef structure as their primary habitat.
Even more worrisome than ocean acidification for the lophelia coral, in particular, are destructive fishing practices, most notably bottom trawling. This practice of dragging large, heavy fishing nets along the seafloor destroys deep-sea coral reefs by scraping corals right off of the bottom and flattening the three-dimensional habitat. With an extremely slow growing species like the lophelia coral, destruction of even a small area of reef, by a single boat, may require thousands of years to recover. Given the amount of bottom trawling that occurs throughout this species’ range, it may be at risk of endangerment. Scientists believe that bottom trawling has destroyed one third to one half of all lophelia coral reefs in Norway, one of the regions with the highest historic density of this species. As a result, Norway has closed several large areas to this practice. Without continuing precautions in regions where lophelia corals thrive, some ancient, deep-water coral reefs may be lost.
Engage Youth with Sailors for the Sea
Oceana joined forces with Sailors for the Sea, an ocean conservation organization dedicated to educating and engaging the world’s boating community. Sailors for the Sea developed the KELP (Kids Environmental Lesson Plans) program to create the next generation of ocean stewards. Click here or below to download hands-on marine science activities for kids.