Coral at risk as Red Sea epidemic decimates sea urchins.

An epidemic spreading through the Red Sea has killed off an entire species of sea urchin in the Gulf of Aqaba, imperilling the region's uniquely resilient coral reefs. The probable culprit is a disease-causing ciliate parasite that brings with it a fast death. Sea urchins play an important role in maintaining balance by feeding on algae that would otherwise block sunshine and smother the reefs. The researchers suggest creating an isolated population of the remaining sea urchins that could hopefully be reintroduced later on.