Coral reefs are one of the most beautiful sights underwater. The dazzling coral reefs are under threat due to the rising temperature of the seas and oceans, which in turn is the result of the global warming phenomenon. Approximately half of the world’s coral reefs have been lost in the past 30 years. It’s only after this great catastrophe that scientists are trying to make sure that we do not lose any more of this wonderful underwater ecosystem. Coral reefs do not just support marine species, they also support almost half billion people globally. Let’s take a look at the reasons why coral reefs are in danger of being wiped out:
What is bleaching
Corals are found in tropical waters, and are invertebrates. Calcium carbonate is secreted by corals in order to build a protective skeleton, which grows and has a kind of symbiotic relationship with the algae which lives in its tissues. The colourful algae provide the coral with energy and give it its vibrant color.
Corals are suffering due to greater temperature fluctuation of the seas, very low tides, acidification, over-fishing, pollution, agricultural runoff and coastal development. The warm temperatures worldwide are causing them to expel the algae which reside in them, robbing them of their color and energy. Corals are extremely sensitive to temperature and a change of only 1-2 degrees Celsius forces corals to expel algae which makes their white skeletons visible. This process is called ‘bleaching’.
Bleaching is extremely harmful for the coral reefs, as algae behave as their farms, provide them with energy, without which the corals starve and eventually die.
In 1998, the first bleaching event took place, in which 16% corals died. El Nino has also contributed to warming the waters of the Pacific, which led to more bleaching in 2015-2016. The third beaching event is happening right now.
Worldwide phenomenon
Coral reefs around the world have been damaged, from the renowned Great Barrier Reef of Australia to the reefs in the Maldives, Hawaii, Florida and Japan. The Maldivian reefs, which are a great tourist attraction, have suffered tremendously, with 73% of the reefs being damaged by bleaching in March-May 2016.
Even worse was the situation in the Kiritimati coral reefs of the Republic of Kiribati, in the Pacific ocean. Due to the warm water temperatures in 2015-2016, which lasted for a period of 10 months, a mind-boggling 90% of the corals were killed.
Scientists are predicting another heat wave in the ocean, which means that many more coral reefs are going to be affected in the western and eastern parts of the Indian Ocean, as well as South Pacific Ocean.
Drastic Intervention required
Bleached reefs can recover if the temperature of the water cools down, but if the temperature stays high for months together, it will cause the coral to die. This will lead to the reef to be weakened, destroying the habitat of fish and unprotected coastlines (from storms).
The severity of the situation cannot be ignored, as it isn’t something which will occur in the future, but it is happening right now. The world is losing corals very quickly, and 90% of corals would die by 2050. What is required is drastic intervention.
This is only possible when all the people and governments work together to reduce global temperature. If the temperature stays warm, corals are in danger of extinction. Thermal or heat stress has to be reduced in order to allow the corals to recover and heal themselves.
Protective measures that can be effective
Introducing fish which thrive on algae is one protective measure which can be implemented easily and can be very effective. The fish eat the expelled algae which cover the corals, allowing new larvae to go inside the coral and grow. Fish urine provides nutrients to the corals, helping them to recover.
Fossil fuels release greenhouse gases into the atmosphere and cause global warming, reducing their use is imperative right now. All of us have to contribute by reducing our usage or else, a very important underwater ecosystem will be lost forever. And the gloriously beautiful coral reefs, which we flocked to see, will turn into gray graveyards, and become another symbol of the damage done by humans.