Bleached Waters

Jack Scott
4 min readJan 21, 2021

A beautiful underwater ecosystem inhabiting much of the sea life is very quickly dying. All coral reefs could potentially be extinct as soon as 20 to 30 years from now.

https://www.youtube.com/watch?v=QltN3FjwTu0

What are Corals?

To the eye, corals may look as if they are very simple animals. Yes, animals not plants. Corals are made up of thousands of very small animals called polyps.

Polyps have a circular mouth that is surrounded by tentacles that combine and stretch across the animal. Inside the polyps are micro-algae plants that go through photosynthesis. Which is then used as food for the animal.

The micro-algae photosynthesizes during the day. And at night when the animal is asleep, the polyps expand and their tentacles come out. At the end of the tentacle, there are stinging cells that catch anything that swims or floats by.

There are different types of species just like any other animal. The shapes and sizes of the animals depend on the type of species of the coral. Some may just look like a rock, while others can have extravagant shapes and colors.

Healthy Coral at The Great Barrier Reef

Bleaching?

When coral bleaches it isn’t because there is a disease that will come and go. Back in the 1980s when bleaching was first discovered it was first thought to be just a disease or too much exposure to light.

Scientists were trying to figure what was going on, and later found out what was happening to the coral. As the temperature was raised by 3.6 degrees Fahrenheit the coral then bleached. And this pointed right towards climate change. As the ocean gets warmer, more and more coral will begin to bleach.

The ocean is like the coral's body temperature. As the heat of the water rises the coral does something in response to the rising temperature. The coral bleaches as a stress response to the spiking temperature.

Due to this the small organisms that live in the coral are unable to photosynthesize. Since that is the coral’s food source, it is not getting fed. When the small organisms aren’t doing their job, the host makes those organisms leave the animal's body. When the small organisms are out of the host, it leaves the coral with a transparent, bleached white look.

When a coral has a white color it means it has no food and is essentially starving. Because of this, the animal's white skeleton shows. But, when the coral is very white it is still alive. It is just not letting anything grow on it. The coral will most likely not grow or reproduce, so as time goes on it will usually die.

When coral dies it will start to have a fuzzy look to it. The fuzzy look is actually micro-algae, which will just keep spreading. This is an indication that the coral has died.

Bleached Coral in the Great Barrier Reef

Effects of Dying Coral Now and in the Future

Coral and the animals work together and benefit from each other. An example of this is an anemone and a clownfish. The clownfish provides food and the anemone provides shelter. The coral doesn’t exist without the organisms around them and some organisms don’t exist without coral.

The effect of coral reefs dying doesn’t just affect sea life, but also human lives. Coral provides food, construction materials, and medicine. It provides more than half of the new cancer drug research according to Colombia University. Coral also maintains the water quality in the ocean. In some countries, coral attracts many people. Which a lot of times can be that country’s main source of income. Coral also inhabits many fish that people in remote areas live off of.

It is predicted that coral may be wiped out in 20–30 years. Since the first mass bleaching in the 1980s, there was another global mass bleaching in 2010. And five years from that, in 2015, there was another bleaching that happened.

Over the last 40 years, 50% of the coral has died and 30% of The Great Barrier Reef died in 2016. 50% of the Caribbean coral are also dead. These numbers will continue to grow as the ocean continues to heat up due to greenhouse gases and fossil fuels that are being absorbed into the ocean.

Sources

“The World’s Coral Reefs Could Be Gone in 30 Years • Our Infinite Earth.” Our Infinite Earth, 7 Nov. 2018, ourinfiniteearth.com/worlds-coral-reefs-gone-30-years/.

Welch, Laura Parker and Craig. “Coral Reefs Could Be Gone in 30 Years.” National Geographic News, 23 June 2017, www.nationalgeographic.com/news/2017/06/coral-reef-bleaching-global-warming-unesco-sites/#close.

Netflix Documentary Chasing Coral

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