Deep reef corals are among the most fascinating coral formations and can be found – although more sporadically than in the fore reef zone – in a variety of species and formations ranging from depths of 50-70 feet to more than 100-200 feet where abrupt dives usually lead down to the ocean floor.
The structure of the deep fore reef, as well as the corals and biosphere found in this area are quite fascinating. Marked by a slope that gets steeper and steeper with every advancing seaward step, this zone of the coral reef features decreasing sunlight and temperature, as well as fewer waves and more complex currents, which are the main ingredients that make it ripe for a diverse ecosystem.
The Deep Fore Reef
The deep reef is located beyond the reef crest and fore reef, and features a continually increasing slope that leads towards the depths of the ocean/sea in which the coral is situated.
Healthier coral populations are found here, when compared to the ones found in shallower fore reefs and lagoons. This is, in most cases, due to the calmer waters present here and the fact that the corals are less disturbed by external influences.
Water pressure and other changed conditions, such as the increased presence of sediments and decreased temperature has led deep fore reef corals to be somewhat different, usually flatter and more spread out in order to maintain their stability and maximize sunlight exposure. Also, although most species are different from those found in shallow areas, many coral colonies can thrive both in the deeper and shallower fore reef zones.
Uneven sediments that form a single general slope can be found here that make the presence of corals increasingly sparse as the slope and depth of the reef continues to descend. Compared to the shallow water sediment normally found in most coral reefs, these sediments have the specific quality of smaller grain sizes.
Deep Water vs. Deep Reef Corals
It’s important to note the significant difference between deep water and reef corals. Although deep water corals are very similar in appearance to regular coral reefs you’d find on the deeper slopes of the fore reef, they are actually very different, both when it comes to their structure and the ways in which they interact with their environment.
Unlike deep reef corals, deep water species thrive in areas with little or no sunlight simply because they have evolved not to use sunlight at all for the purpose of getting their energy. Instead, they have developed a curious type of metabolism that allows them to survive by trapping tiny organisms and feeding on them almost as carnivore fish would.
Deep water coral formations have been found in numerous areas throughout the world, sometimes as deep as 6000 feet under sea level, and scientists continue to uncover new species through submarine explorations in all the oceans on the planet, found both as individual polyps and larger coral colonies.
Corals, animals and plant life still thrive both in the deep reef zone and further down, even though conditions are significantly harsher and access to sunlight and higher temperatures may be restricted.