Deep Sea Fishes
In the Sea
Sea Pictures and Wallpapers
Pictures of the Sea
Other Sea Information
Deep Sea Diving
Deep Sea Research
Naval Sea Systems
Sea Level Rise
Oceans and Seas
The Aral Sea
The Caspian Sea
Coral Reef and Sea Plants
Coral reefs are one of the best and busiest ecosystems that the earth has. Many types of creatures are found and build their lives around these reefs from the tiniest crustaceans to large creatures such as sharks and turtles, which use the reefs as a feeding ground.
Coral reefs can have different sizes, shapes, and colors. Coral reefs are found in shallow waters of the ocean. Hawaii and Australia are famous for their coral reefs. Some animals that live in coral reefs are starfish, sea urchins, sea anemones, marine fish, clams, sea crabs, and seahorses.
Coral reefs are the most luxuriant and complex of all benthic communities. The largest coral reef in the world, the Great Barrier Reef, stretches more than 2,000 km, from New Guinea southward along the east coast of Australia. Corals are colonial animals, and individual coral animals are called polyps. A coral polyp is very similar to a tiny sea anemone, but extracts calcium carbonate from the water and forms a calcareous skeletal cup. Large numbers of these polyps grow together in colonies of delicately branched forms or rounded masses. Most shallow-water coral colonies also have symbiotic algae living in their skeletons. The algae get protection from the coral and, in turn, provide nutrients for the coral polyps. These shallow reef-building corals require warm, clear, shallow, clean water and a firm substrate to which they can attach. Because the water temperature must not go below 18 degrees C and the optimum temperature is 23 degrees C to 25 degrees C, their growth is restricted to tropical waters between 30 N latitude and 30 S latitude and away from cold water currents. Water at depths greater than 50-100 m is too cold for significant secretion of calcium carbonate. Also, reefs usually are not found where sediments limit water transparency. Until recent legislation banned trawling in deep-sea coral beds off the coast of Norway, the existence of deep-sea corals was known only to a handful of scientists and a large number of fishermen. Along the American east coast several deep-water corals, such as the octocoral Primnoa resedaeformis and gorgonian Paragorgia arborea, are common inhabitants of the upper and middle slope faunas in the canyons south of Georges Bank. Deep-water coral colonies can be found in a variety of shapes and forms, from branched trees to conical mounds. Like shallow corals, they require a hard surface to settle on and grow.
Given that the existence of these remarkable species has been known for more than a century, it is striking that almost nothing is known about their biology, population status, the role they play in enhancing local species diversity, and their role as habitat for deep water fishes, including those recently targeted by fishermen. The rarity of encounters with octocorals during recent submersible dives across the shelf of the northeast U.S. suggests that distribution of these species has significantly declined in the past three decades. These slow-growing species may live for centuries, yet be destroyed in seconds by human activities such as trawling and dredging. Trawling with rolling gear has allowed even larger and heavier gear into their rugged canyon homes.
Sea Corals - Symbiosis
The most important part in the building of a coral reef is the symbiotic relationships with zooxanthellae. There are also many natural polymers found within the species that occupy these realms. The most commonly found polymers are protein and cellulose, and cellulose is by far the most abundant.
There are creatures called sea cucumbers, obviously because they look like cucumbers, but are really living animals. They have strong muscles that contain protein.
Sea cucumbers also have a slime trail that they secret. The slime trail is made up of mucopolysaccharides. To better understand this I will break this word down. Muco means mucus, or in other words slime. Polysaccharide is a natural polymer; in fact it is the building block for many things. It is also known as a type of sugar.
Polysaccharide can be broken down into glucose molecules, which can be found in virtually all of the food we eat!
Another creature that lives around coral reefs and also secretes a mucopolysaccharide is a nudibranch. The nudibranch uses this secretion to find prey or possibly attract a mate. They are also known to contain Glucosaminoglycans (GAGS) that is used in medical applications for treating joint, ligament and tendon conditions. Chondroiten, a Glucocaminoglycan substance, is thought to have uses in treating arthritis.
Among the many creatures living within coral reefs are plants. These plants provide photosynthetic operations. This just means that they use sunlight to make oxygen, which has to be really interesting since they are under the water. They also contain cellulose. Cellulose is not the only polymer found in plant cell walls. There are other materials, but they have not been researched completely enough to explain all of their potential uses.
The group of organisms called Sea anemones is similar to the jellyfish only these creatures don't move around as much. They mostly stay in one place, such as a coral reef, but they do have the ability to move. Sea anemones, such as Metridium senile have layers of mesoglea that are a source of collagen, a type of protein. Plus their inside core is made up entirely of protein.
Coral looks like a flower but can sting like a bee. Thousands of coral polyps live in a colony to form a coral reef. Reefs are like underwater versions of rain forests full of fantastic shapes and structures and life. The builders of the reefs, the coral polyps, have radial (rotational) symmetry. In this lesson, students will learn about radial symmetry and then have an opportunity to build symmetrical designs using pattern blocks. The lesson will take about an hour but the post viewing symmetry activities can continue as long as interest is sustained. Students will learn about coral reefs while listening to a narrator read a New England Aquarium book, Dive to the Coral Reefs. Students will discover scuba diving as a way of exploring the coral reefs. They will get a chance to "pretend" dive with a partner, check dive equipment before diving, and then explore the wonderful underwater world of the reefs!
Sea Coral Research
In recent years scientists have discovered deep-sea corals and/or coral reefs in Japan, Tasmania, New Zealand, Alaska, California, Nova Scotia, Maine, North Carolina, Florida, Colombia, Brazil, Norway, Sweden, UK, Ireland and Mauritania. Because research submarines and remotely operated vehicles suitable for studying the deep sea are few and expensive to operate, scientific investigation of these remarkable communities is in its very early stages. But it is increasingly clear that deep-sea corals usually inhabit places where natural disturbance is rare, and where growth and reproduction appear to be exceedingly slow. Deep-sea corals and sponges may live for centuries, making them and the myriad species that depend on them extremely slow to recover from disturbance.
Sea Coral Conservation
Unfortunately, just as scientists have begun to understand the diversity, importance and vulnerability of deep-sea coral forests and reefs, humans have developed technologies that profoundly disturb them. There is reason for concern about deep-sea oil and gas development, deep-sea mining and global warming, but, at present, the greatest human threat to coral and spongecommunities is commercial fishing, especially bottom trawling. Trawlers are vessels that drag large, heavily weighted nets across the seafloor to catch marine fishes and shrimps. Scientific studies around the world have shown that trawling is devastating to corals and sponges. As trawlers become more technologically sophisticated, and as fishes disappear from shallower areas, trawling is increasingly occurring at depths exceeding 1,000 meters.
It is not too late to save most of the world's deep-sea coral and sponge ecosystems. It is commendable that nations including Australia, New Zealand, Canada and Norway, which have already taken initial steps towards protecting some coral and sponge ecosystems under their jurisdiction. United Nations and appropriate international bodies should establish a moratorium on bottom trawling on the High Seas. Similarly, individual nations and states should ban bottom trawling to protect deep-sea ecosystems wherever coral forests and reefs are known to occur within their Exclusive Economic Zones. They should prohibit roller and rock hopper trawls and any similar technologies that allow fishermen to trawl on the rough bottoms where deep-sea coral and sponge communities are most likely to occur. They should support research and mapping of vulnerable deep-sea coral and sponge communities. It is expected of them to establish effective, representative networks of marine protected areas that include deep-sea coral and sponge communities.
Types of Corals
- Hard Corals
Hard corals are made of solid calcium carbonate or limestone and emerge very much like rocks. Each polyp secretes a solid exoskeleton made up of calcium carbonate. Hard coral polyps have a crumbly internal skeleton that stays in place after they die.
- Examples of Hard Corals
Hard corals, scientifically known as "scleractinians," can frequently be viewed in public aquariums. Brain coral is a type of hard coral and the many convolutions in its plane account for its name. Elkhorn coral and pillar coral are two important examples of hard corals.
- Soft Corals
Soft corals are also poised of some hard calcium carbonate, but it is blended with protein so it is less dense than hard corals. These corals are "rooted," but because they have no exoskeletons, they bend back and move forward with the currents, appearing to be more like plants blowing in the wind.
- Examples of Soft Corals
Soft corals, also called "gorgonians," and they are also used to add charm to aquariums. Few examples of soft corals are red sea fans and rods that bob and bow with the progress of the water.
A coral reef is an edge close to the surface of the water that is poised of colonies of polyps. The polyps secrete calcium carbonate that make up their external skeleton, and when one dies, another build on top of it.
Types of Coral reefs
- Patch Reefs
This type of reef occurs beside the continental shelf, or the fixed underwater land adjoining continents, where the water levels are low enough for the coral to grow.
- Fringing Reefs
These reefs will be found along rocky coastlines where the coral will start to extend outer parallel of the shoreline. Because the coral is made up of aquatic life, the coral will not expand on to shore and will maintain to move off shore and will drop once in deeper waters. This is known as the reef slope.
- About the Great Barrier reefs or Bank reefs
In some condition, coral reefs will be formed far from the shore of continents. In these cases, the coral reef is usually adjoining small islands or even the border of the continental shelf. Unlike other reefs, barrier reefs will not stick together with the mainland but will develop on all sides. The water between a barrier reef and the shore is known as a lagoon. bank reefs are like barrier reefs.
Type of coral in the Great Barrier Reef
Atolls are strange because they start as fringing reefs around oceanic volcanoes. The islands formed by oceanic volcanoes start to sink over long periods. As the island sinks, the fringing reef will go on rising. The island will become undersized, and the fringing reef will develop into a barrier reef. As the island sink, the barrier reef will become spherical in nature, with a huge, deep lagoon in the middle. As the island disappear below sea level, the corals will continue to construct upon one another, forming a rounded coral reef know as an atoll.