The Crown-of-Thorns Starfish (COTS), known scientifically as Acanthaster planci, is a formidable presence in marine ecosystems. As the world’s second-largest starfish, COTS are not just notable for their size but also for their impact on coral reefs. Covered in venomous spikes, these starfish are causing widespread damage to reef systems, particularly in iconic environments like the Great Barrier Reef. This article explores why COTS are such a concern and the strategies being employed to mitigate their harm.
A Toxic Menace
Crown-of-Thorns Starfish are covered in sharp, venomous spines that pose a threat to both humans and marine life. The neurotoxin in their spikes can cause severe stinging pain and potential liver damage in humans, and the impact on marine creatures can be equally devastating. The real danger, however, lies in their feeding habits.
COTS are voracious predators of coral polyps—the tiny, living organisms that form the structure of coral reefs. When COTS populations surge, they can decimate large areas of coral, turning vibrant and complex reef systems into barren expanses. This feeding behaviour poses a serious threat to the health and sustainability of coral reefs.
The Great Barrier Reef: A Case in Point
The Great Barrier Reef, the largest coral reef system on the planet, has been particularly hard hit by Crown-of-Thorns Starfish outbreaks. The extensive loss of coral due to these starfish has significant repercussions for the reef’s biodiversity and overall health. Coral reefs are not only vital for marine life but also play a crucial role in supporting human economies through tourism and fisheries.
The damage inflicted by COTS extends beyond the loss of coral. As the reef structure deteriorates, it disrupts habitats for countless marine species, leading to a decline in biodiversity. This, in turn, affects the entire marine food web and ecosystem stability.
Targeted Control Measures
Addressing the Crown-of-Thorns Starfish problem requires a targeted approach. In the Great Barrier Reef, a specialised control program is in place to manage COTS populations. Trained divers are employed to locate and treat these starfish with either bile salt (derived from the liver of oxen) or vinegar. These substances are effective in neutralising the starfish’s venom and causing their death without causing harm to the surrounding coral or marine life. (GreatBarrierReefFoundation,2024)
This targeted control program is designed to mitigate the impact of COTS while preserving the delicate balance of the reef ecosystem. By focusing on individual starfish and using environmentally safe chemicals, the program aims to reduce the number of COTS and allow the coral reef to recover more effectively.
Broader Implications and Ongoing Efforts
While targeted control programs have shown promise, the broader issue of reef health remains complex. COTS outbreaks are just one of many stressors affecting coral reefs, including climate change, ocean acidification, and pollution. Addressing these challenges requires a multifaceted approach that combines local conservation efforts with global climate action.
Research into the causes of COTS outbreaks is ongoing, as understanding these factors is crucial for developing more effective management strategies. Additionally, public awareness and community involvement play a vital role in supporting reef conservation initiatives.
Conclusion
The Crown-of-Thorns Starfish poses a significant threat to coral reefs, particularly in regions like the Great Barrier Reef. Their impact on coral health and reef biodiversity highlights the urgent need for targeted intervention and comprehensive conservation strategies. By addressing the COTS problem and other environmental pressures, we can work towards preserving these vital marine ecosystems. The health of coral reefs—and the myriad species they support—depends on our collective efforts to safeguard our oceans for future generations.