I am sure that in this day and age most educated people around the globe know or have least heard of the terrible depletion of the worlds Coral Reefs and the reasons that the leading marine scientists blame for the problems!
Global warming gets all the blame for everything nowadays but in reality it should not! Many issues are to blame for the problem of Coral Death and man himself does have a part to play but also cannot be totally to blame!
Some of the causes are the work of man such as: Illegal dumping of Chemical and Toxic Waste being dumped at sea! Agricultural Pesticides and Fertilizer being washed from the farms into the Rivers and to the Oceans! Untreated Sewage being dumped directly into the Rivers and Oceans! Household Garbage including Cleaning Chemicals and Plastics being dumped on the shores! Oil Spills from Maritime Disasters and many more Human Interactions all contribute to the general degradation of the water quality which in turn affect the all creatures which live in the Oceans including some of the more fragile species, the Corals!
Man is always easy to blame but we cannot hold him completely guilty as there is another component which can create and cause immense amounts of destruction and that is Mother Nature Herself! She can be blamed for Typhoons, Cyclones or Hurricanes, it depends where you live as to what name you choose to call these horrific storms, She can smash a coral reef to pieces in a very short time by slamming flotsam such as fallen trees and other objects directly onto the reefs! Yes, she is mean when she wants to be (just like my sister) but still has an evil trick up her sleeve because when all the weather is quiet and peaceful, lurking in the depths are some of the most efficient coral killers in the Ocean, The Crown of Thorns Sea Stars!
Most people will have never seen or heard anything about the Crown of Thorns as it is seldom seen except by Scuba Divers and Fishermen but it is a very great threat to many kinds of coral species! In Australia, on the Great Barrier Reef they discovered this problem many years ago and to date they still have not found the reason for the sudden outbreaks of them and more so they have not found any efficient method of dealing with the problem!
The Crown of Thorns is a multi-legged Sea Star which grows to the size of a dinner plate, can be different colors from Green to Purple and it feeds on the corals by turning its stomach inside out in order to dissolve and devour the helpless coral polyps! So far so good but the description so far sounds like any simple Star Fish but the Crown of Thorns as the name suggests still has a Wicked Defense Strategy as each of its spines is like a Hypodermic Needle loaded with a very Toxic Venom and when man comes in contact with this pain is immediate and the wounds can take a long time to heal as I found out some years ago when our group of divers were collecting a group of Crown of Thorns from a shallow reef! We all had sacks to collect them in but one diver turned around and the current caught his sack and it hit me on the calf muscle and I was stung several times, Ouch said I, or something to that effect, to cut a long story short, one puncture wound would not stop weeping fluid for about 2 months and about 10 thousand peso’s later, after a further month the wound healed but has left a nice depression in my leg to remind me of that day!
The different ways to deal with them start with the simplest method which is to collect them in sacks , baskets or string them in Tuna Fishing Line like a Necklace and get them out of the water as this is the way to kill them as they are 80% water, on land they dehydrate and die! Sodium Bi sulfate can be injected into them under water and this will kill them but a specialized injection system is required! Whichever method is to be used, the diver should be extremely careful and try not to get injured by the stings! If you do get stung we have found out from experience that if you squeeze the wound straight away under water until you get as much of the venom as possible out of your body then on land soak the wound in hot water there is a good chance that you will not be very badly hurt! Some people have chopped them up and left them in the water but unfortunately the have a special power which gives them the ability to grow a complete new creature from each piece, just like the Terminator! There are natural predators to deal with these creatures but the Triton Shell which eats them is also a great delicacy for fishermen and the large Groupers and Wrasse have been nearly fished out in many areas!
Unfortunately, when a plague of Crown of Thorns appear they should be removed from the water as quickly as possible but if the government gets involved there is a maze of paperwork to get through before any funds can be issued in order to stop the problem so its usually up to the private sector to attack the problem first! Some years ago, there was a huge outbreak near Glan at the tip of Sarangani Bay, in order to stop the problem, the Rotary Club of Metro Dadiangas along with a Sister Club from overseas raised funds to pay the local fishermen 1 x KG of rice for every 20 Crown of Thorns they removed! For every 5 KG of rice they also got 1 can of fish! At the end of the project, 126,000 Crown of Thorns had been removed and the plague was at an end! To get the local fishermen to remove them is the cheapest and most efficient way to deal with these creatures that we have discovered to date!
Now, on every dive, some divers carry a sack or a piece of Tuna Line in case they see any Crown of Thorns on their dive, if they see any then they remove them! There numbers can be controlled as long as you stay on top of the problem, its no use to plan ahead if there is a plague in your area, you must act immediately as each on can eat around 1 square meter of coral per week so you can imagine what kind of damage to a reef 500 can cause if left unchecked! If you could eat them then they would not be a problem but to date I have not discovered any one who can find any use for them!
When we remove them from the water they are just left to dry out in the sun and then buried but they can be dug into the ground as a fertilizer! As long as there are plenty of them then we will keep on catching them! It is nice to think that one day we will have won the battle with the Crown of Thorns but to be honest, I think that such an idea is just a dream and they will always be around! Lets hope not!
(Note) Many Crown of Thorns WERE killed during the taking of the Pictures!