How did things get so bad? What is it that is threatening the reefs?
 
Next to the effects of global warming, discussed in my previous post, there are also more local activities that threaten the corals. These are some of them:
 
Unsustainable fishing
 
Overfishing is a big threat for the corals because overfishing affects the entire food web. Though corals live in a symbiotic relationship with a certain algae (zooxanthallae), there are other algae that need to be kept under control for the health of a coral colony, for example: seaweed. Many fish and other sea creatures eat the seaweed and this keeps a good balance for the corals. But when due to overfishing the fish that feed on these algae are in numbers too low to keep the balance, the corals become smothered by out of control growing weeds.
 
Blast or cyanide fishing use dynamite and poison, respectively, to trap and/or stun fish. Cyanide fishing is often used to capture the fish alive so they can be sold in pet shops and put in aquariums. Large fish can metabolise this substance but smaller animals, also corals, are unable to and are poisoned in this way. Blast fishing as you can imagine can destroy whole coral colonies in a split second.
Then there is also bottom trawling in which a weighted net is dragged along the sea floor to catch whatever it meets. This destroys about everything on its path.
 
A video on fishing using dynamite: https://www.youtube.com/watch?v=1Y_8x4TGm3A
 
But corals do not only suffer from the effects of the hunt for other species, they themselves are also taken from their habitat (in whole or pieces are broken off).
Corals are mined and turned into bricks or roadfil. Sand and limestone derived from corals can be turned into cement.
Heavily harvested are also the black and red corals. They are beautiful and therefore used for the creation of jewellery. Branched corals are often broken apart and sold in pieces or as a whole as souvenirs or as home decoration.
Since corals grow maybe an inch per year, a colony might have taken hundreds of years to grow. It will also take this amount of time (or more with the new adverse conditions of global warming) for the population to restore what is taken away.
 
Pollution
Beaches are often left littered by their visitors. Trash left on land and ships can be blown by the wind into the sea. Floating trash can get entangled in the reefs and start to block the corals from the sunlight they need.
Animals living in the reef areas can often not distinguish a floating plastic bag from a jellyfish and will eat the trash thinking it is food. Death and decline of the population that the corals need to keep their environment in a perfect balance are the result.
Sewages are discharged into the oceans. Other land based activities like farming, logging, road construction, animal husbandry and mining come with pesticides, fertilisers and sediments that run off from land into oceans. Also sunscreen gets mixed into the water. All this (and more) causes an abnormal high amount of nutrients, bacteria, chemicals and pathogens to enter the marine system. Too much nutrients disturb the natural balance and promote the growth of algae that can block the corals from sunlight. Too much sediments have the same effect.
 
Another impressive video. A fishing net weighing 11 tons caught in a reef: https://www.youtube.com/watch?annotation_id=annotation_436135601&feature=iv&src_vid=1Y_8x4TGm3A&v=ki3znMJCpGo
 
Destruction
Destruction by construction, by boat anchors or not well managed tourism is also a great factor for the decline of coral reefs.
Piers or other structures have been built right on top of coral reefs causing their destruction and eliminating their possibility for regeneration.
Boat anchors are dropped on the reefs, also greatly damaging them.  An easy solution for this is to install permanent mooring buoys which float on the water. This can be used by fisherman or tourists operators as a place to safely anchor their boats.
As mentioned in an earlier post, the corals also bring tourism, but when this is not well managed it can really harm the reefs. Snorklers and divers need to be careful not to grab or kick the corals because this can break them. Also need they be mindful not to stir up the sediment from the ocean floor not to cause the corals to become smothered.
 
Mangrove destruction
Not only the direct destruction of the reefs is a danger for them. Also the destruction of other habitats is really affecting the corals. Yes, everything really is connected!
The destruction of mangrove forests (for firewood, to make space for beaches or aquaculture farms) takes away a beautiful ecosystem that serves as a nursery where reef species like fishes can grow up. Also are the mangroves a filter of the amount of sediment that reaches the ocean. Without this filter more sediments reach the coral reefs.
 
Coral reefs not only need to be preserved for their beauty. Since they support about 25% of all marine life, they are a very important part in the food chain, they are very important in keeping the balance in the world. A little more about the role of the reefs you can read here: https://mspsteem.com/nature/@mirjamsvideos/why-are-corals-so-important-join-me-on-my-journey-to-go-restore-coral-reefs
 
We should protect all life in the ocean, not just the coral reefs. The ocean provides food and medicine, regulates the planet´s climate and hereby regulates life on earth. If you want to know more about the services our ocean provides, take a look here: http://oceanwealth.org/ecosystem-services/

I am making an effort to spare our environment and next to that for some reason, coral reef restoration has caught my interest. At the moment I am learning diving, taking an online course in Oceanography and I am comparing the organisations that work to restore the reefs. Like this, in some time, I will be qualified to follow a course in coral reef restoration at the organisation of my choice.

Thanks for reading my post! Already wishing you an amazing 2019!!

Sources:
https://coral.org/coral-reefs-101/reef-threats/
http://wwf.panda.org/our_work/oceans/coasts/coral_reefs/coral_threats/
https://oceanservice.noaa.gov/facts/acidification.html