Coral-eating crown of thorns starfish have become a danger to Australia’s world heritage-listed Great Barrier Reef. A major outbreak of the creatures are feeding on the reef. Researchers from the reef’s Marine Park Authority found the starfish in plague proportions at the southern edge of the Great Barrier Reef last month. The starfish is native to the reef.
The predatory starfish uses digestive enzymes to feed on the corals after spreading its stomach over them. According to Hugh Sweatman, a senior research scientist at the Australian Institute of Marine Science, each starfish eats about its body diameter a night. He said that a lot of coral will be lost if something isn’t done. The starfish also have poisonous barbs that are harmful to humans.
The Great Barrier Reef, covering 348,000 square kilometers, is the most magnificent and extensive coral reef ecosystem in the world. The reef has already suffered from two consecutive years of major coral bleaching. In 2016, the worst-ever coral bleaching on record killed two-thirds of a 700km stretch of reef.
The damage from the starfish has prompted the government to begin culling the marine animals. Most of the culling efforts are focused well south of the most-visited sections of the Great Barrier Reef. Unfortunately, the area is remote and hostile, making it difficult for authorities to control the spread of the coral-killing starfish.
The cause of the latest outbreak is still a mystery to scientists and the Marine Park Authority.
There have been four major outbreaks of the crown of thorns starfish in the Great Barrier Reef since the 1960s. The outbreaks are usually triggered by extra nutrients in the water. For that reason, outbreaks are usually further north and closer to the coast. Each time, the reef has recovered from the damage.
Officials are hopeful that the reef will recover this time as well. The Authority’s director of education, stewardship and partnerships, Fred Nucifora, said the coral species primarily present in that area are the faster growing staghorn and plate corals. The reef also has a healthy population of fish, which will aid the regeneration of the reef.