What does the crown-of-thorns starfish primarily feed on?

The crown-of-thorns starfish is a large starfish that preys upon hard, or stony, coral polyps. The crown-of-thorns starfish receives its name from venomous thorn-like spines that cover its upper surface, resembling the biblical crown of thorns. It is one of the largest starfish in the world.

It has a very wide Indo-Pacific distribution. It is perhaps most common in Australia, but can occur at tropical and subtropical latitudes from the Red Sea and the east African coast across the Indian Ocean, and across the Pacific Ocean to the west coast of Central America. It occurs where coral reefs or hard coral communities occur in the region.

The body form of the crown-of-thorns starfish is fundamentally the same as that of a typical starfish, with a central disk and radiating arms. Adults normally range in size from 25 to 35 cm (9.8 to 13.8 in).

The adult crown-of-thorns is a predator that usually preys on reef coral polyps. It climbs onto a section of living coral colony using the large number of tube feet on its oral surface and flexible body. It fits closely to the surface of the coral and then extrudes its stomach out through its mouth over the surface to virtually its own diameter. Their stomach secretes digestive enzymes that allow the starfish to absorb nutrients from the liquefied coral tissue. This leaves a white scar of coral skeleton which is rapidly infested algae. An individual starfish can consume up to 6 square metres (65 sq ft) of living coral reef per year.