While the interference of humans is a large part of why various coral reefs are slowly dying, it turns out that the Great Barrier Reef may be in danger from another problem: a hungry starfish.
The Hungry Starfish
While the idea may seem somewhat comical, deadly starfish are a major issue due to their feeding on piece of the world’s largest reef system. Already threatened by the rising ocean temperatures, this is just another piece of a major problem that may lead to the demise of this vibrant environment.
The problem species is known as the Crown-of-thorns starfish, a native species that is growing so quickly that they are posing a serious threat to the health of the reef. The species is so prevalent that they have been detected on 37 separate sections of the southerly Swain reef – located more than 60 miles away from the shore.
The New York Times talked with Fred Nucifora, a spokesman for the Great Barrier Reef Marine Park Authority, who said that “whenever coral in any location in the Great Barrier Reef is threatened or stressed, it is of concern.”
The death of the reef would be catastrophic. As one of the planet’s largest living structures – even big enough to be visible from space – it is home to thousands of species including turtles, whales, and sharks. The impact of the coral reef dying would also be felt in Australia, which relies on the area for around 70000 jobs and billions of dollars in tourism revenue each year.
Each species has its niche, and this hungry starfish normally fills its role by eating the fast-growing coral species and allowing the slower-growing cousins to flourish. However, considering the massive spike in Crown-of-thorns starfish population levels, the coral are now being killed faster than they can reproduce.
The marine park authority has been doing their best to control the situation, culling more than 600000 starfish from the northern and central reef areas since 2012, according to Nucifora.
The New York Times reports that one study between 1985 and 2012 found that the reef had lost an average of 50 percent of its coral. The deadly starfish was responsible for almost half of that decline, with the other damage caused due to bleaching and tropical cyclones.
We don’t currently know why the population of the Crown-of-thorns starfish is growing so rapidly. There are multiple theories, with one hypothesis suggesting that currents in the area are delivering nutrient-rich water from the deep sea up to where the starfish live in the reef, which would assist starfish larvae growth.
The recent outbreak is especially concerning consider the rise in frequency of coral bleaching, a disastrous event that has happened multiple times in recent history due to global warming. It’s normal for coral reefs to undergo a cycle of death and renewal, but the current problem is that there isn’t enough time for the reef to recover between death events. If we’d like to preserve the thousands of species and thousands of jobs that rely on the Great Barrier Reef, we’ll need to take quick action to address both the damage of the starfish and global warming.