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Out of Control Cancer The harmony of communications between all the microscopic cells of a human body keeps the old system humming along. If some of the cells stop hearing the music and start replicating too quickly, they can go into a feeding frenzy, eating everything they can get their little membranes around. And the symphony that was the individual being consumes itself from the inside out. In medical terms this is called cancer. Most cancer cells start out as valuable members of the community before they loose the beat. Normally, when the balance gets upset and one type of cell starts getting too numerous and starts attacking other cells, the cops show up. In the cellular community these are called macrophages (big eaters). They devour the cells causing the problem and keep things in control. Cancer happens when the control networks break down. Even the police system can go haywire, as in Leukemia when Macrophages start eating all cells, good and bad alike. There are several reasons why some members of living systems lose control. Human cells, for example, become cancers from stress, chemicals, smoking, radiation, and even disease organisms. Coral reefs get cancers, too, and one of the most interesting of coral reef cancer stories is that of the crown of thorns starfish.
By most people's standards, the crown of thorns, Acanthaster planci, are ugly. They have 16 to 18 arms and are covered all over with long, venomous spines. A big one can be half a meter in diameter. An electron microscopic picture of the tips of their spines show a molecularly sharp crystal point. The spines are so sharp they slide through skin, and most gloves, without any real pressure; just glide in. Then the venom - a nerve toxin - gives an instant lesson on why one should leave these starfish alone.
Crown of thorns starfish are found on coral reefs in the tropics ranging from the Red Sea, throughout the Indian and Pacific Oceans, and all the way to the Pacific coast of Panama. They eat coral. Not the coral skeletons, just the delicate tissues of the coral polyps. Since coral flesh is just a thin film on the outside of the coral skeleton, and since the polyps can withdraw down into protective little cups, coral is not very easy to make a meal out of.
A hungry starfish climbs up on a coral and pulls its stomach out of its mouth with its tube feet. The starfish has thousands of these flexible tube feet, each ending with a little suction cup. The feet pass the stomach from one to the next until the big yellow stomach is spread out over the coral. Then the stomach slooshes the live coral with digestive juices. The cells of the stomach scoff up the bits of dissolving coral. When the starfish has cleaned the coral right back to the white calcium carbonate skeleton, it sucks in its stomach and walks off, using those tube feet. Normally, there are not very many Acanthaster on a coral reef. Maybe one every kilometer of reef or less. Many reefs don't seem to have any at all and, of course, the starfish is absent entirely from Atlantic coral reefs. Usually, Acanthaster live near coral reef passes. Maybe they help keep the passes open by trimming corals. Maybe they just like the current. Back before the sixties, not many people had ever seen or heard of the crown of thorns starfish. The diving biologists of the forties and fifties surveyed many miles of coral reefs and even very experienced diver/biologists had never even seen one. Then, in 1962, reports of a strange bloom of these creatures surfaced from Green Island, just of Cairns in Queensland Australia. The Queensland government asked Dr. Robert Endean, an Australian marine biologist who specialized in venomous sea creatures, to check it out. He returned from the field with tales of millions upon millions of starfish devouring the coral reefs around Green Island and other reefs on the Great Barrier Reef. He urged instant action. The government buried his report. He went to the press. The government said Endean was exaggerating, there was no problem, not really. Bob, furious, escalated the controversy but in the end, his report stayed buried until, years later, I managed to get the US State Department to request the report under a scientific trade agreement. The starfish did not care one way or the other. As a specialist in coral reefs and echinoderms (starfish included) I discovered another infestation in Guam in 1968. It had been in progress for perhaps three years when I arrived at the University of Guam. The biologists recognized the reefs were in trouble, but were not sure what the problem was. I knew what was wrong the instant I saw the crown of thorns there on the reefs of Guam. Lots of them. Thousands. Hundreds of thousands. Stripping the living coral from the intertidal zone to the depth limits of coral growth at the rate of one kilometer of shoreline a month. There were two fonts, moving out from an epicenter at Tumon Bay. Ahead of the front the coral was alive. Behind the coral skeletons were bare, slowly being covered with a gray algae. The colorful coral reef fish moved ahead of the bands of starfish, trying to remain in their adaptive habitats, uncomfortable in the dead coral environment. The stripped reefs looked desolate, colorless, compared to the unharmed reefs.
So why? What causes a normally uncommon coral reef predator to become so abundant and over-strip it's environmental limits? Why did these starfish become a cancer of the reef?I studied the problem for 6 months and began a control effort to stop the coral destruction. The results of my study were published in the July issue of Science. You can download a reprint of this study by clicking on the following link: I organized a crown-of-thorns survey of the north Pacific from Hawaii to Palau, and the Northern Marianas Islands to Kapingimarangi. The expedition was supported by the U.S. Department of the Interior and managed by Westighouse Ocean Research Laboratories. I headed a team of 63 diver/scientists that were divided into groups of 10 and sent out to survey conditions in as many locations as possible. It was the largest single survey of the condition of coral reefs ever organized. I published details on how the Acanthaster survey was organized in Oceans Magazine. You can download the PDF file of this article with the following link: Chesher, R.H. 1970. Acanthaster: Killer of the Reef. Oceans Magazine 3(5):10-17 The final report of the survey was published by the National Technical Information Service and was instrumental in obtaining millions of dollars for future research and control efforts. You can download a PDF copy of this rare report by clicking on the following link; The survey teams found other infestations of crown of thorns starfish in different stages of development in many island areas - usually in close proximity to villages or urban areas. There was no "common denominator" to clarify the cause of the population blooms. Instead, the picture that emerged was that blooms are likely to occur where the reefs are stressed. And the reefs of the world are stressed by many different causes. What sorts of things stress reefs? Increased water temperature can cause coral to eject their symbiotic algae - a process known as coral bleaching. If the temperature stays too high too long the corals die and are quickly covered with blue-green algae. The Crown of Thorns starfish spawn during the hottest months of the year and if the larvae settle on a recently bleached reef they will have a very high survival rate. People blast reefs with dynamite and, as in Guam, damage the coral by dredging. The adult crown of thorns, and even their swimming larvae, are attracted to the metabolites released by damaged corals. When the adults are attracted to the damaged coral metabolites they will find plenty of partners for enhanced spawning success and of course the larvae they create will have an excellent chance of survival. People also break coral when walking on reefs, to catch octopus, crabs, and collect shells for tourists or get coral rocks for building material. Reefs are over-fished. At least two species of large fish eat the crown of thorns. They are gone from most reefs near people. People poison the reefs with various chemicals to kill or stun fish. Agricultural chemicals applied to island gardens or used to control mosquitoes wind up in the sea, and in the corals. This weakens the corals. When the crown of thorns eats the coral they accumulate these chemicals in their own tissues (it does not seem to harm them, the larvae actually survive better with DDT in the water). The predators of the crown of thorns, including triton shells and a beautiful little shrimp, may die or encounter breeding problems from the concentrated poisons in the starfish's flesh. Increased concentrations of carbon dioxide in the sea water reduces calcium deposition, slowing coral growth. All of these stresses create an opportunity for the Crown of Thorns to become a cancer of the reef. And then there is the triton. The beautiful triton. Dr. Bob Endean said, right away, he thought the cause of the starfish explosion was because the triton were over-collected. Other biologists, including me, thought this unlikely. But now, after investigating the infestations for over 30 years, I think Bob was right after all. Or partly right. Certainly the tritons are a major predator on the starfish. And they are over-collected, even endangered or locally extinct, in most areas of the Pacific. Many critics of the idea that triton predation is significant point out one triton can only eat one big Crown of Thorns every day or so and there are thousands of starfish during an infestation. But the critics forget the normal population of Crown of Thorns starfish is just one or two individuals per kilometer of reef. Tritons could easily be a major factor in controlling the starfish in normal conditions. Plus during spawning, the Crown of Thorns assemble and spawn together. This attracts any tritons in the vicinity and when a triton attacks a Crown of Thorns any nearby starfish take off at high speed (they can almost outrun a Triton). This would have a major impact on the spawning success of the starfish.
As with any cancer, there may be many contributing causes of the infestations. But the plight of the triton is symmetrically balanced with the escalation of starfish numbers. Everybody loves the triton. Or at least they love its shell. People make horns, bookends, door stops, or just decorations of these glorious shells. They sell for as much as $100 for a nice one, sometimes more. Virtually every single island diver, man, woman or child, grabs every single triton they see. A multitude of recreational and professional skin and SCUBA divers grab every one, regardless of size, sometimes just happening across one, sometimes avidly seeking them out. Tritons normally come out to feed at night. Just as the Crown of Thorns normally feeds at night. These days, many island spear fishers also go out at night and underwater flashlights are found in the smallest island village stores. Tritons are not hard to see at night, either. Even small tritons stand out sharply against the background of a coral reef. Glorious colors and graceful shape. In Florida, at a "Shell Factory" I found thousands of tritons from all over the Pacific. From tiny little ones only as long as my thumb to big ones the size of my forearm. The biggest tritons make the most eggs. Big ones are quite rare now. I have interviewed older divers in many islands of the Pacific and they all agree that the triton population has gone down to practically nothing. You can still find them in shell shops and in markets, getting fewer, smaller and more expensive each year. The reason I think the triton is especially important in this whole crown of thorns problem is because the triton/starfish relationship is easy to understand, easy to sympathize with, and - in theory - easy to do something about. After all, nobody NEEDS to kill tritons. The only reason we kill them is because they are beautiful and we like to have their shells for decorations. On the other hand, they are key species and killing them endangers the whole coral reef ecosystem. The people who live on the islands rely on the coral reef ecosystem for fish and other protein. The small amount of money a few individuals might make selling a triton they found will in no way compensate for the loss of protein for the whole community following a crown of thorns attack. American Samoa spent nearly half a million dollars just fighting the starfish. Every sale of every triton ever collected from their reefs did not total that much money. So, logically, you would think it would be easy enough to do something about this aspect of the problem. You would think the island governments would leap to the rescue of the triton, banning collection and sales. In Australia, the government did just that. But it still permits importation of tritons from other countries, like the Pacific islands, and there are plenty of tritons in gift shops just inland of the Great Barrier Reef. There is no way to know if they came from the Great Barrier Reef or Fiji, is there? In Fiji, tritons are protected. But almost every gift shop has a few and you can find them for sale in the public market. Nobody has ever been fined or even had their triton confiscated in Fiji. Nobody. Not ever. New Caledonia is the only country in the South Pacific where tritons are a protected species and killing, transporting, handling, disturbing, buying or selling Tritons - alive or dead - is forbidden. Tonga will not protect its tritons because, "People like them. It's tradition." Nobody would enforce a ban anyway.
CITES. Biologist Ann Paulson and I managed to get Australia to propose listing Tritons on the Convention against International Traffic of Endangered Species (CITES). Japan objected, and Australia withdrew it's suggestion. Scientists have spent millions of dollars investigating the Crown of Thorns. The vast amount of scientific research on the crown of thorns over the past 30 years has been very interesting. Scientists are now spending more millions investigating coral bleaching, and a host of coral diseases that flourish in the wake of human abuse of the coral reefs. As science learns more about the control systems regulating the population explosions of the crown of thorns, the consensus is finally showing in many synergistic combinations, human abuse of the coral reef ecosystem is behind the problem. Or at least making it worse. A conclusion reached in 1968 and gradually gaining acceptance. In 1962 the Queensland government did it's best to sand bag the whole problem. I suspect the politicians realized something right away. Something marine biologists have still not thought of, even though it's pretty obvious. The control system that is out of wack is larger than the control web in the oceans. The problem is not the triton, it is the society that collects the triton, killing them because people adore their beauty. Focus on that. How do you reconfigure that control system? Going back to the cancer analogy, we know smoking contributes to human stress. We know it results in cancer as well as a host of other diseases. Nobody NEEDS to smoke. But people like it, and even kids do it even if it is against the law. See the parallel? Here is the problem to solve. Here is the control system out of wack. Scientists can study the details of coral reef demise for the next 30 years, spending millions to confirm and reconfirm the obvious. So? How will that solve the problem? It won't. Starfish as cancers of the reef are going to continue. So what do we do about it?Option 1. Nothing. Let it happen. It's nature. Just like any cancer they happen, kill the organism or ecosystem and eventually, possibly, one day the reefs will recover. Or maybe they won't recover because humanity is going to continue to stress the reefs and as the populations of these cancerous reef creatures increase the chances of the coral reefs ever reaching their former magnificence diminishes. Option 2. Remove the cancers when they are discovered. Medical doctors don't study the progress and demise of their cancer patients. They remove the cancer and improve the health of their patient to prevent the cancer from happening again. Doctors don't ascribe to the "let nature take it's course" especially when nature's course has been deflected by bad behavior. It's easy enough to remove the cancerous starfish from the reef. I developed the technique with my volunteer control team in Guam back in 1968. It has been improved by discovering vinegar will kill the starfish without causing any collateral damage. Get some multiple shot veterinary syringes (like the Automatic Drenching Vaccination Dose Gun Syringe 20mL Livestock Veterinary syringe on Amazon $25) and some enema bag kits with silicon hoses (about $10 on Amazon). Attach the silicone hose to the syringe, fill the bag with white cleaning vinegar, and inject the starfish twice on the disk at the base of the arms with 20cc (two shots). In 24 hours it will be dead. One diver can inject about 300 starfish in an hour or two in a major infestation. So with 4 volunteers a large infestation can be eliminated in a day or two. The vinegar changes the pH of the Acanthaster's body fluid and after it is dead the pickled starfish can decompose or be eaten by crabs or fish without harming them. There is no adverse effects on the surrounding corals. Just the opposite because the corals are still there. It's best to start at the advancing edge of the infestation to prevent further damage to the corals then work backwards to eliminate the following starfish. The area should be checked daily for at least a week to catch any starfish that might be migrating in from wherever the swarm originated. Control efforts should be done before the spawning season if possible. Ideally from March to September when the starfish gonads are not ripe. Some researchers warn that injecting them during the spawning season might trigger them to spawn. But even it it did - and there is no evidence that it does happen - that is like saying "leave them alone to spawn naturally". That's illogical because when they spawn naturally they choose the right weather, the right time, and assemble to assure a successful spawn. That would, of course, result in a lot more starfish than if they were induced to spawn when they were scattered and being injected. I've watched them spawn and they like to take their time. Political Control HazardsThe vinegar tactic was developed by a Queensland researcher and by a researcher in New Caledonia. The New Cal researcher works at IRD (Institute for Research and Development) and he tested the system in Vanuatu with volunteer local divers. He also helped set up an Acanthaster reporting website where the diving community can post alerts of infestations - what reefs they are attacking, how many per 20 minute swim - the date of observation. All good stuff. We - and others - posted sightings of a massive infestation at Ilot Mato on the IRD website and - because some really magnificent corals were being destroyed - I contacted the IRD researcher and asked when they might be mounting a culling expedition. But he was in France and wasn't sure when they might be able to do anything. We wanted to set up a program so recreational divers could help cull the starfish and organize culling expeditions to major infestations - starting with Ilot Mato. My veterinarian fiend offered to supply the repeating syringes at very low cost at his clinic. Since many of the most important coral reefs are nature reserves killing the starfish in a nature reserve would require special permission from the natural resources department. My friend knew the president of the department well and she said it would not be a problem but the permission could only be given to an organization, not an individual. He got together with some other divers and set up a New Caledonia Pleasure Boating Association but the Natural Resources Department could only provide the exemption after getting an OK from the New Caledonia Congress. They also contacted IRD who contacted the French Expert on Crown of Thorns who had developed the culling technique. He responded with a warning. It was illegal, under the New Caledonia environmental code and the Fisheries Act, to use any chemical in the marine environment that caused harm to any marine organism. The law was set up to prevent people from using poisons to kill fish and it's a very important law. Violation incurred a fine of thousands of dollars and confiscation of the fisherman's boat. So before the Congress could give permission to a public organization to cull the starfish in the parks - or anywhere in New Caledonia - the Fisheries Department would have to make an exemption to the law to allow the use of Vinegar to cull the starfish. Fisheries refused to allow any exceptions and said it would require an act of Congress and they would not ask for it. And there was a number of people at IRD and in the Natural Resources Department that maintained that the Acanthaster infestations were a natural event and should not be stopped. Finally after about 3 months of meetings and confusion the association was given authorization to proceed but with certain restrictions. 1. Any culling expedition had to have at least one IRD senior scientist observer. 2. The association had to provide at least 3 weeks advance notice of the date of the culling dive. 3. Any participants had to undergo training by IRD on how to do the injections. Of course nobody could possibly know what the weather would be like for diving out in the lagoon in shallow coral reef areas three weeks in advance. And "volunteers" would never get organized three weeks in advance anyway. Plus the IRD staff had a very busy schedule and could not be sure of going for a dive three weeks in advance. The result, massive coral mortality at Ilot Mato, one of New Caledonia's most well developed and beautiful coral reef ecosystems. The infestation reached it's peak in 2020, during COVID, and boats were not allowed out into the lagoon during the epidemic. Check out the before and after images of the damage caused by the Acanthaster. Since then the IRD continues to survey infestations, counting starfish, taking photos, posting on Facebook and writing reports. They are, accoring to the researchers, forbidden to undertake any control actions. There is an obvious solution to the problem. If IRD won't cull the starfish and citizens are not allowed to do it the only organization that could easily control the infestations without even spending time or money that isn't already allocated is the Lagoon Protection Brigade of the Provence Sud.
According to the Provence Sud web page, "The South Province takes action on a daily basis to preserve the richness of our lagoon. With a regulatory framework, human surveillance on the ground, an operational centre in the event of a disaster and environmental monitoring by independent scientific experts, the Province is doing everything it can to look after this universal asset." When IRD sends a report of an infestation to the South Province the Protection du Lagon Brigade has the boats and personelle already out there in the lagoon, perfectly capable of removing the Acantaster Cancers and doing what they are mandated to do; protect the lagoon. Not happening. Why not?
https://tellusconsultants.com/Thread/ACANTH.HTM |
Crown of thorns starfish
are one of the oceans most efficient coral predators. 
