Mentioning the word, corals, brings about warm, clear tropical seas and reefs with beautiful colorful fish to the mind. The one aspect, however, is just one of the types of coral; there are deep water and soft corals found in the cold waters of the seas.
Corals are classified as marine invertebrates that live in compact colonies of identical individual polyps. They are sessile animals, attaching themselves permanently to the ocean floor. We cannot identify corals by body parts, faces, like other living organisms.
Corals are formed through a partnership called symbiosis, which is beneficial to plant and animal life in the ocean. We consider corals as animals since they don’t make their food as plants do. Polyps secrete calcium carbonate that attaches to dead skeletons of polyps or rocks.
A polyp has an opening on one end to feed. When food has been fully utilized, the polyp in the same mouth expels the waste products. There are tentacles around the mouth that are used for feeding-capturing small animals, defense mechanisms, and clearing of debris.
What are Aquatic Corals Made of?
Corals use nematocysts, which sting tentacles to capture their food. They are found around the tentacles and the outer tissues. The nematocysts are capable of producing toxins that are powerful to bring down their intended prey. Depending on the size of the coral, the prey size could be small fish or microscopic animals. In this article, you will obtain a better understanding of the elements that create a coral!
Zooxanthellae
The coral is a type of algae that is planted and resides within the coral tissues. They have a symbiotic relationship with the corals. The corals provide the algae with a conducive environment for photosynthesis, and in return, the algae give oxygen and a medium to dispose of waste produced by the corals.
Zooxanthellae give glycerol, glucose, and amino acids (photosynthesis products), which the corals use to make carbohydrates, fats, proteins, and the production calcium carbonate. The corals use 90% of what is produced by the photosynthesis process.
Also, zooxanthellae can be credited with the beautiful colors on the stony corals. In stressful circumstances, polyps produce their algal cells that make the coral take a stark white appearance called coral bleaching. Corals can die if they stay long periods without zooxanthellae.
Reef-building corals behave like plants because of the symbiotic relationship with these algae. They require clear water for sunlight penetration. Light is crucial in aquatic survival.
How Stony Coral is Formed
The secretion of calcium carbonate by polyps leads to the formation of reefs, though stony corals have but a few polyps. As reefs grow, they become structural habitats for sea organisms, both vertebrates, and invertebrates. Polyps can contract into their body when they are physically stressed living with no part exposed above their skeletons. Otherwise, it’s in their nature to extend out, when they are feeding.
There are varieties of coral shapes and sizes that can be attributed to the species. Some are soft, rounded, and hard pointed shapes.
How do Coral Reefs Grow?
Coral larvae attach themselves to rocks that are submerged and start secreting skeletons from under their skin. The body can provide protection and also a substrate where new polyps can attach themselves. This process consumes more energy, which is supplemented by the zooxanthellae. The species determine the rate at which corals will grow depending on the water salinity, temperature, food, and turbulence.
Staghorn and branching corals grow the fastest in a year adding around 20cm, while massive corals are the slowest with an addition of 5-25 millimeters a year. Corals reefs do well in warm, clear, shallow waters with temperatures of 70-85 0 F, corals, however, need salty waters to grow.
How do Corals Reproduce?
Through asexual reproduction, new polyps bud off to form new colonies or to expand. Coral species are broadcast spawners that release numerous sperms and eggs into the water to distribute their offspring over a broader area. The sperms and eggs join forming planulae, which are produced in thousands to counter the risk of many hazards.
The production of the sperm and eggs occurs around the same time as the male and female corals don’t move into reproductive contact. The distances between colonies are wide, so the release must be broadly timed and precise. Some corals are hermaphrodites, meaning they produce eggs and sperms at the same time.
Spawning in the long-term is determined by day length, temperature, or rate of temperature change. The short-term spawning is based on the lunar cues, and spawn is related to the sunset time. The matter swims to the surface towards the light, where currents transport it for two to three weeks. The coral then moves downwards to favorable conditions where they metamorphose into polyps to form colonies that increase in size.
Value of Coral Reefs
Coral reefs are the most economically valuable and biologically diverse ecosystems on earth. Coral ecosystems:
- Protect coastlines from erosion and storms
- Source of food to millions
- Source of recreation for economies
- Provide spawning, habitat, and nursery for fish species
- Source of new medicines
- Marine biodiversity.
Coastal Protection
Coral reefs are rough and have complex structures that break the force of incoming waves; it buffers shorelines from waves, storms, and currents, helping in the prevention of erosion, loss of life and damage to property. Coastal lines protected by coral reefs are a source of sand for natural sand replenishing.
Biodiversity
Coral reefs are a habitat, breeding, nursery, and feeding grounds for the different organisms. There are numerous varieties of species living in coral reefs than any other ecosystem on earth. Coral reefs support more than 4000 species of fish and more than 800hard coral species.
Tourism and Recreation
Scuba divers dive deep into the water to visit coral reefs to enjoy the variety of sea life. Local and international tourists visit beaches protected by coral reefs. Billions of dollars are gained from the tourists that frequent the coasts to enjoy the sand and sunshine.
Medicine
Some creatures found in the coral reefs have produced promising medicines in the field of cancer, arthritis, ulcers, asthma, heart disease, viruses, and other diseases. Also, they have become new sources of nutrients, cosmetics, and enzymes. The remedies from the coral reefs have made it gain a name in the 21st century as the medicine cabinet.
Fisheries
Research has shown that fish that grow in the coral reefs feed billions of people worldwide. Many in America and South East Asia depend on the fisheries from these areas with coral reefs. Over $ 100 million is generated from fisheries in the US alone due to coral reefs.
Natural Threats to Coral Reefs
Coral reefs are unique and powerful when they stay over sometimes; however, climatic conditions cause tremendous damages to the reefs. Cyclones and hurricanes can flatten or break apart large coral heads. Algae can overgrow on slow-growing coral reefs. Tidal emersions also affect exposed coral heads. Damages caused during the day are dire due to the ultraviolet radiation that can dry out and overheat the coral reefs. Weather patterns like the Elnino can cause devastating physiological effects on coral reefs. Predation is another factor to be wary of since corals are vulnerable. Persistent stresses to corals either caused by natural causes or human can lead to the death of corals.
Human activities are known to destroy the existence of many living and nonliving organisms and the extinction of many species. Pollution is one of the many ways a human can remove the population of corals. Sewage treatment, coastal development, agriculture, and deforestation are but a few examples of how human activities can directly or indirectly cause pollution to coral life. Coral diseases can be due to biological or non-biological stresses that as; viruses, fungi, and bacteria or pollution, ultraviolet radiation, and increased sea temperatures. Coral disease frequency can be attributed to human interference, as scientists believe. Problems have become so severe to the ecosystems that have been there for generations. There are steps that you can follow to keep your corals safe and clean.
Final Thoughts
Corals reefs are the most economically valuable and biologically rich ecosystems on the planet. They provide jobs, protection, food, and income to billions of people in the world. Coral reefs are in danger of being extinct if care and measures are not taken to curb the abuse dealt with them.
With some government realizing that the coral reefs are in danger and set up bodies to protect the sea life is a unique achievement for the corals and for other nations to follow. The human race needs to wake up and try not to be the greatest enemy of coral growth. Setting up Marine Protected Areas is called for in this day and age for the coral reef life to survive. Coral reefs are a beauty to see and let’s embrace what nature has offered. Endangering the home for so many organisms is neither fair nor just.
