Endangered Coral Reefs

Corals are animals (not plants!) that belong to the phylum Cnidaria which is a scientific classification based on characteristics of the animals within the group. Other cnidarians include jellyfish and sea anemones. There are soft corals and stony corals; the stony corals have a calcium carbonate (limestone) skeleton while the soft corals are mostly soft tissue polyps. As a coral dies or "bleaches," the calcium carbonate skeleton may become exposed.

Corals are not plants, but they do get some energy from photosynthesis via symbiotic algae that the corals host within their cells. You can think of a symbiotic relationship as a partnership; the coral hosts the algae as a place to live while the algae provides energy to the coral.

Corals group together to form colonies which result in their calcium carbonate structures forming the foundation for large coral reefs. Often referred to as "rainforests of the sea," coral reefs create one of the most biologically diverse underwater habitats in the world as they are home to thousands of species of fish, crabs, shrimp, snails, worms, clams, and of course the actual corals themselves. The coral reef structures provide plenty of cover which allows animals to seek shelter from predation. All of these animals living within the coral reef attracts predators and the result is a food chain within the coral reef community.

Endangered coral reef habitats are home to a very large percentage of marine animals even though the habitats themselves only cover an extremely small portion of the ocean floor. This is why these reefs desperately need public awareness and support.

Scientists estimate that coral reef habitats only cover approximately 0.2% of the ocean floor. That is less than one percent! Of this extremely small cover area of coral reefs, scientists also estimate that over 25% of monitored coral reefs have been destroyed.

Can you believe that such as tiny fraction of the ocean is home to over a million species of fish, invertebrates, and algae? This extremely high biodiversity is why coral reefs rival the rainforests.

In addition to the approximately 25% of coral reef habitat that has been lost, scientists have predicted that about 1/3 of current coral reef habitat may be lost over the next couple decades due directly to human activities.

Since the beginning of the industrial revolution and the use of fossil fuels, the earth's atmosphere has seen dramatic increases in carbon dioxide levels.

Carbon dioxide that enters the atmosphere is also absorbed by the ocean (scientists suggest about 1.4 of the carbon dioxide in the atmosphere enters the ocean). In the ocean, carbon dioxide lowers the pH of seawater which results in increased acidity. Carbon dioxide also reacts with carbonate ions and water to form bicarbonate molecules. This severly reduces the ability to form calcium carbonate.

According to the NOAA, the ocean has become 30% more acidic since the beginning of the industrial revolution.

The difficulty in forming calcium carbonate in an acidic environment results is reduced populations of animals that have calcium carbonate components such as the shells of many sea creatures and the calcium carbonate skeleton of corals. Reduced coral growth means a reduction in coral reefs.

Combined with other factors, this means that not only are coral reefs being destroyed but now they are having an even more difficult time growing back. Increased destruction and reduced growth in coral reefs is a recipe for disaster.

Blast fishing is an extremely destructive method of fishing in which fishermen use explosives, such as dynamite, to kill large amounts of fish at a time. This makes it very easy for the fishermen to collect all of the dead fish instead of having to actually capture them.

They just toss in an explosive, wait a couple seconds, then collect all of the fish.

Not only does this kill all of the fish, but it destroys the coral reef habitat in the process. This means that the other fish that weren't involved in the blast no longer have a home. It can take several years for a single blast site to recover. The coral reefs simply cannot repair themselves quickly enough to keep up with coral reef destruction occuring every single day.

A single blast may only take a few seconds, but it will take years for the habitat to recover (if it even can recover).

The saltwater aquarium trade is a worldwide hobby consisting of both private and commercial aquariums that rely on fresh stocks of fish and invertebrates collected from the ocean. Some fishermen, but not all, use a very deadly form of fishing known as cyanide fishing, or cyanide stunning.

Cyanide fishing is a method in which a diver brings a bottle of cyanide poison down to the reef where he/she sprays the fish with the cyanide chemicals which stuns the fish. The stunned fish make for a very easy capture since they can't rapidly swim away and hide from the diver.

The cyanide used to stun the fish for easy collection kills the surrounding coral reef affected by the spray. Not only does cyanide fishing kill the coral reefs, but it also kills some of the fish which means divers must spray a larger amount of fish than what needs to be collected as a means to offset their "losses."

Besides coral reef death by cyanide, live stock is depleted from coral reefs by collection for the aquarium trade. Corals simply cannot grow fast enough to offset the losses.

Take a look some photos of coral reef communities below and ask yourself the following questions:

If endangered coral reefs continue to decline then, as a human, would you feel OK if you knew that these communities were wiped out as a result of human activity?

Wouldn't you want to do everything you can to prevent this from happening?

*Note: all of the images below are courtesy of AllPosters.com