Starfish Threatens Great Barrier Reef

A few weeks ago I mentioned how millions of tiny crustaceans were eating up a Japanese island. The cause was a rise in ocean temperature that increased the plankton in the water.

Scientists in the Great Barrier Reef have found another change in an ocean ecosystem that is likely the cause of human activities. This time its an increase in the population of the crown-of-thorns starfish in the Great Barrier Reef which is affecting the health of the coral.

This starfish, which can grow to 40 cm in diameter,

“devours coral reefs by climbing and extruding their stomach over them in order to excrete a digestive enzyme which transforms the reef into consumable, liquefied tissue. Though the reason behind this current starfish outbreak is not entirely clear, it is believed that it could be linked to agricultural runoff, which increases algal blooms that nourish the starfish larvae.” - TreeHugger

So the ecosystem around these beautiful creatures is changing with a decrease in the starfish’s natural predators, water salinity, temperature and impact from human activities. The starfish haven’t changed but have increased in number throwing the delicate ocean ecosystem out of balance. The researchers noted there was hope for the coral and the best way to handle the “outbreak” was to decrease human activities that impact the habitat.

Via TreeHugger

Image: Jon Hanson