Crown Of Thorns
Crown of Thorns Starfish are one of the biggest threats to the Great Barrier Reef, along with climate change, bleaching, illegal fishing and water quality. The Crown of Thorns starfish have been responsible for 40% of coral cover loss on the great barrier reef since 1985.
Crown of Thorns are not invasive or introduced, they are naturally found on the Great Barrier Reef. If they reach outbreak proportions, however, the animals have the potential to greatly alter the structure and biological diversity of the reef ecosystem. The animals are corallivores, meaning that they feed primarily on live coral tissue.
A healthy reef is not just about healthy coral. Healthy coral supports a vast array of marine species which all closely interact to keep the entire reef ecosystem healthy and thriving. Although Crown of Thorns are naturally found on the Great Barrier Reef, problems have arisen in recent decades due to human interference with the natural system and processes, allowing populations to reach outbreak proportions.
Crown of thorns starfish are highly successful reproducers and the biggest problems in recent years have been removal of their natural predators due to overfishing, along with increased nutrient loads from a land-based run-off and poor land management practices. One single individual can have up to 65,000,000 babies and their young thrive on excess nutrient loads in the ecosystem. This, combined with a lack of natural predators means that the populations of Crown of Thorns starfish have been able to proliferate to very large numbers and have become difficult to control in certain areas.
The great news is that the Great Barrier Reef Marine Park is one of the best managed protected areas in the world and there is a great deal of research, science and management being undertaken to better understand and control this reef threat. Luckily, Lady Musgrave is far enough from the mainland to escape any water quality issues from runoff, and the fact that we operate within a protected, “no-take” green zone means that the area is somewhat protected from overfishing.
We at Lady Musgrave Experience keep an eye on the reef for potential Crown of Thorns outbreaks. We love involving our guests in this important monitoring and conservation activity. Our citizen science programs have in the past identified when the crown of thorns have increased above naturally occurring numbers. By reporting this information directly to the marine park management authorities, we are able to manage and reduce the threats with early intervention and a proactive and fast response. You can learn more about Crown of Thorns Starfish and get involved in such monitoring and control by signing up for our Marine Biologist for a Day experience.