Scientists have discovered that a swarm of coral-eating starfish that has generated panic due to their seemingly relentless attack on the Great Barrier Reef may be killed off with a simple dosage of household vinegar.
Crown-of-thorns starfish, along with cyclones, are thought to be one of the two main causes of the Great Barrier Reef’s rapid loss of coral cover during the last 30 years.
When the conditions are favorable, such as when phytoplankton, their food source, becomes more abundant due to floods washing fertilizers and other contaminants from land into the water, the starfish can become plague-like.
A recent starfish outbreak has chewed through significant portions of the reef, pushing scientists to come up with novel measures to stop the disease.
Researchers at James Cook University have discovered that a single injection of vinegar kills the coral-eating starfish completely.
All starfish given 20ml of vinegar died within 48 hours, according to university experiments. The study will now move on to sea trials.
Currently, to kill a starfish, divers must inject 10 to 12ml of ox bile into it. Unlike vinegar, which is readily accessible in the grocery, ox bile is expensive, requires many licenses, and must be combined to the proper concentration.
However, the breakthrough isn’t a vinegary silver bullet; there’s still no other way to deliver the vinegar except by injecting starfish one by one.
The lead author of the JCU report, Lisa Bostrom-Einarsson, said more research was needed to guarantee the vinegar did not harm other sea creatures.
“There’s no reason to believe it won’t work or be unsafe,” she said, “but we have to be sure.”
“It is estimated that there are between four and twelve million starfish on the Great Barrier Reef alone, with each female producing approximately 65 million eggs in a single reproductive season.”
“With two full-time boat crews, they managed to kill roughly 350,000 people last year.” While culling them all that way would be impossible, we know that continuous efforts can conserve certain reefs.”
Crown-of-thorns eradication efforts are funded by the federal government, with 27 maritime tourism companies and two community groups certified to eradicate them.
However, according to the most recent report card on the Great Barrier Reef’s health, targets for reducing chemical runoff are not being met, making future outbreaks more likely.
How do you stop a crown-of-thorns starfish?
Given the dangers COTS bring, scientists and resource managers have devised a number of strategies to keep them under control during an outbreak. Taking starfish ashore and roasting them in the sun, burying them, injecting them with poisonous chemicals or compressed air, and constructing underwater fences to regulate their movement are some of the tactics used.
Divers and snorkelers should be extremely cautious in the water when dealing with a COTS outbreak. To safely combat breakouts and eradicate the species from the reef, local dive operators, resort workers, and tourists should attend training sessions and seminars focusing on COTS ecology.
Check out the global COTS database to learn more about potential occurrences and implications, especially if you live in the Indo-Pacific area. While it is impossible to prevent COTS outbreaks, targeted attempts to remove the species have proven to be effective in preventing the destruction of reefs by these hazardous sea stars.
What causes outbreaks of crown-of-thorns starfish?
In the scientific world, this subject has been explored and argued for a long time. It has become increasingly obvious as a result of this research that outbreaks are unlikely to be caused by a single source. Instead, it’s more likely that a number of elements work together to create the right conditions for an outbreak to start, including:
- the biological characteristics of crown-of-thorns starfish that allow colonies to grow and reproduce fast in the correct conditions
- reductions in the number of natural predators of crown-of-thorns starfish, which may improve the capacity of crown-of-thorns starfish populations to expand and reach epidemic levels.
- surplus nutrients from run-off or natural upwelling that give additional nourishment for crown-of-thorns starfish larvae to live and reproduce
- Ocean current patterns that disseminate crown-of-thorns starfish larvae in a way that favors outbreak development
- the availability of enough live coral as a food supply to sustain the outbreak’s population.
Does vinegar kill crown-of-thorns starfish?
A new weapon in the fight against coral-eating crown-of-thorns starfish is on the way, and it’s a condiment.
The Great Barrier Reef Marine Park Authority and James Cook University conducted field studies at Arlington Reef, off the coast of Cairns, and found that a dash of home vinegar supplied through injection is harmful to the voracious starfish.
The findings are good news for more than 30 people and businesses, mostly in the tourism industry, who have been given permission to cull starfish under the Authority’s control program to protect the Reef and their livelihoods.
“The persistent predator has been responsible for a huge percentage of coral fatalities over the last 50 years but it has an Achilles’ heel,” Dr Mary Bonin, project manager for the Marine Park Authority Crown-of-thorns starfish, stated.
“They die after 48 hours of being injected with white vinegar, which contains acetic acid, and begin to disintegrate.”
According to a thorough environmental impact study of the trial areas, the vinegar-laced starfish pose no hazard to other marine species.
In fact, fish species that eat dying crown-of-thorns starfish were discovered to like them just as much “Pickled” starfish is a term for a starfish that has been
“Dr. Bonin added, “We have footage of these species actively feeding on dead crown-of-thorns starfish that have been injected with vinegar.”
“And assessments conducted before and after the field trial show that there was no effect on fish populations.”
Vinegar is both less expensive and more accessible than bile salts, the most often employed substance to cull the starfish at the moment, and is readily available on grocery shelves for roughly $0.60 per litre.
A single, lethal 20 mL dosage of household vinegar, injected at the base of a starfish arm with a modified drench gun, costs around a penny.
“Due to quarantine controls and specialized import permission requirements, access to bile salts might be problematic in poor nations, as well as for business operators and the general public in other countries,” Dr Bonin stated.
“The chemical is also costly, and once combined in solution, it has a five-day shelf life, which can drive up expenses for small-scale control programs because unused solution may have to be thrown.”
Crown-of-thorns starfish Project Manager Steve Moon of the Association of Marine Park Tourism Operators said vinegar has the potential to be a valuable and cost-effective solution in Australia and abroad.
“He said that “any new invention in the struggle to lower crown-of-thorns numbers is always welcome.”
“The ability of tourism operators, isolated communities, and developing island nations to contribute more effectively to crown-of-thorns control will be substantially enhanced by the use of vinegar as an alternative control method.”
The Marine Park Authority has released revised instructions for control permit holders on how to utilize the vinegar solution.
“It’s a mix that, according to Dr. Bonin, “perhaps indicates a new stage in the effort to turn the tide on COTS infestations that are threatening the Reef.”
Our website has information on how to obtain a permit to conduct crown-of-thorns starfish control.
Physical Removal
Once the starfish has been retrieved from the water, the animals can be burned or buried on land. If COTS are buried in soil, they can be used as fertilizer or compost. Fill a big container with fresh water and submerge the COTS for at least 48 hours if you are at sea on a ship or boat. After a certain amount of time has passed, it is safe to dispose of the starfish in the open ocean, at least 50 miles off the coast. The low cost of this method for COTS removal is appealing, and the COTS can be composted or utilized as fertilizer. The removal of COTS requires a significant amount of physical effort, which can be risky.
Chemical Injection
Chemical injection is another COTS eradication strategy used by the Great Barrier Reef Marine Park Authority and other large organizations. Oxgall and Bile Salts No.3, as well as vinegar, are the most prevalent and environmentally friendly chemicals used today. In the past, more harmful chemicals such as bleach, copper sulphate, and sodium bisulphate were utilized. Chemicals are kept in a sealed container with a high-pressure hose connecting it to an injection cannon. At the base of the starfish arms, the poison is administered with a needle or a continuous injection device.
However, some chemicals are hazardous to the environment and other organisms, making this process more efficient than manual starfish harvesting. Chemical injections are often more expensive, and obtaining the necessary supplies can be challenging. If a chemical is injected wrongly into a starfish’s arms, the COTS can shed and regenerate them, preventing the chemical from spreading throughout the creature. The injection can sometimes cause the starfish to spawn, which isn’t ideal. COTS have a high reproductive success rate, with current research estimating that a giant female starfish can generate up to 60 million eggs in a single spawning season. Again, during COTS management methods, it is critical to avoid inducing spawning.
Mutilation
Finally, mutilating COTS (pulling them apart) has been used to eradicate the starfish, although this procedure is not encouraged and can potentially increase the problem. COTS have the ability to regenerate limbs that have been severed, making tearing them up pointless. As previously established, starfish can spawn when they are irritated or stressed. COTS can be gathered and placed in mesh bags that are submerged as an alternative. Because they can’t move, the starfish will eat up all of the oxygen at high densities. They usually perish within two to three days. This procedure is, once again, not recommended.
Are crown-of-thorns starfish invasive?
- Purple sea urchins (Strongylocentortus purpuratus) are native to the United States’ Pacific Coast. Natural predators of the purple sea urchin, such as sea otters and sea stars, have declined in numbers (Pearse 2006). The resulting population explosion of purple sea urchins has ravaged kelp forests, which are important homes for many marine animals (Pearse 2006).
- Europe and North Africa are home to the European Green Crab (Carcinus maenas). The crab, which is found in the Americas, Australia, and South Africa, preys on a wide range of creatures but is especially damaging to bivalves (Colnar & Landis 2007).
Do crown-of-thorns starfish cause coral bleaching?
Crown-of-thorns starfish outbreaks have wreaked havoc on the Great Barrier Reef’s several reefs since 1962. In the World Heritage Area, a fourth outbreak is now ongoing.
Crown-of-thorns starfish (also known as COTS) are coral-eating marine invertebrates. They’re found on reefs all around the Indo-Pacific, and when the conditions are right, they may spread like a plague, decimating hard coral communities.
After coral bleaching, crown-of-thorns starfish are a major driver of coral loss on the Great Barrier Reef, according to our research.
On the Reef, AIMS manages a large crown-of-thorns starfish monitoring program. Over a 15-year period, this long-term study found that epidemics start in the north and travel south, with ocean currents moving larvae between reefs.
The surveys also reveal that good reefs rebound after outbreaks, but it takes 10 to 20 years. However, reefs that are subjected to additional stresses, such as coral bleaching, cyclones, or poor water quality, take longer to recover, and the coral may not fully recover before the next round of breakouts.
What eats a crown-of-thorns starfish?
The gigantic triton snail, humphead Maori wrasse, starry puerfish, and titan trigger fish are all predators of adult crown-of-thorns starfish. Shrimp, crabs, and polychaete worms are all predators of immature starfish.
How long does a crown-of-thorns starfish live?
Although the wild life expectancy of crown-of-thorns starfish is unknown, they do age and reach the senile stage after 3-4 years. The majority of the specimens tested perished between the ages of 5 and 7.5 years. They can live for 8 to 15 years in captivity.
What happened to the crown-of-thorns?
The thornless remnants are housed in the treasury of Notre-Dame Cathedral in Paris, where they survived a horrific fire that devastated the roof and spire of the church in April 2019.
What do crown-of-thorns starfish look like?
The crown-of-thorns starfish (Acanthaster planci) has a central disk from which its arms emerge, similar to other starfish. They have many soft arms (more than the usual five) that are covered in spines, which distinguishes them from other creatures. Their arms are also prehensile, allowing them to grasp objects. Crown-of-thorns starfish can grow up to 10-14 in (25-35 cm) in length and have more than 20 limbs when fully grown. They’re also available in a range of colors, including bluish-purple, red, gray, and green.
How cute are they?
The COTS (a coral predator) is more interesting and appealing than cute. Their brilliant colors, such as purple, gray, and green, as well as their spiky body, are fascinating to observe.
How do they communicate?
The method these organisms communicate is mostly unknown. A recent study, however, may give some illumination, as it was discovered that they communicate with one another through chemical release. COTS from different places, such as COTS from the Indo-Pacific region (which are a coral reef pest) and COTS from Japan, have been found to release the same compounds. When they are attacked by a predator, they appear to emit various proteins, but there is still a lot more to discover about these fascinating aquatic critters.
How big is a crown-of-thorns starfish?
The average adult crown-of-thorns starfish is 10-14 inches long (25-35 cm). The long and pointed spines on the sides of the starfish’s arms and upper (aboral) surface resemble thistles, and can have up to 23 arms. They resemble a crown, which gives the animal its name. The spines are solid, pointed, and may easily puncture through fragile surfaces, growing up to 0.13 ft (4 cm) long.
How did it get its name?
The venomous thorn-like spines that cover the upper surface of the crown-of-thorns starfish (coral reef eater) give it its name. These resemble the biblical crown of thorns in appearance.
Would they make a good pet?
They cannot be kept as pets because they dwell in the waters and contribute to the balance of their ecosystems. Crown-of-thorns starfish are predators that eat a variety of corals. They can only live in the deepest parts of the ocean, where they may feed on vast amounts of corals.
Kidadl Recommendation: Only purchase pets from a reliable provider. It is important that you conduct your own research as a potential pet owner before deciding on your pet of choice. Being a pet owner is extremely rewarding, but it also necessitates a significant amount of time, effort, and money. Check to see if the pet you’ve chosen is legal in your state and/or nation. You must never capture wild animals or harm their habitat. Please double-check that the pet you’re thinking about buying isn’t an endangered species, isn’t on the CITES list, and hasn’t been captured in the wild for the pet trade.
Did you know…
One of the most interesting crown-of-thorns starfish facts for kids is that they feed on their prey, coral reef, by ejecting their stomachs from their bodies and covering the corals!
Crown-of-thorns starfish are nocturnal and can eat 53.8-140 square feet (5-13 square meters) of coral in a single year. COTS are the primary cause of reef damage in Australia’s Great Barrier Reef.
The poison of the crown-of-thorns starfish contains saponin, a chemical component that is deadly to both humans and fish. The sting of a crown-of-thorns starfish can produce numbness, tingling, nausea, and agony across the body.
On the Great Barrier Reef, AIMS has a large COTS checking operation. This long-term study found that epidemics start in the north and move south over 15 years, with the ocean transporting larvae between reefs.
Why is the crown-of-thorns starfish a problem?
Coral-eating crown-of-thorns starfish can be an issue. Under extreme circumstances, this sea star can have outbreaks that cause huge coral reef devastation, threatening the vital coral cover. Coral reefs are crucial for many undersea animals, and they also help to reduce the intensity of the waves that pound our coasts.
Can a crown-of-thorns starfish kill a human?
Although the venom of crown-of-thorns starfish (coral reef eater fish) cannot kill humans, their spines do contain neurotoxic and starfish poison, which is harmful to both humans and marine life.
We’ve painstakingly crafted a variety of interesting family-friendly animal facts for you to explore at Kidadl! Learn more about the ground beetle and the American dagger moth, two more arthropods.
You can even color one of our crown-of-thorns starfish coloring sheets at home to keep yourself occupied.