Researchers may be able to use "shocks" caused by weather changes to bring declining coral species back to life.

"We are unlikely to be able to keep many of the world's reefs in a pristine state, but with good management we may be able to maintain them in a coral-dominated condition and in some cases we may be able to bring back reefs from a degraded state," Dr. Nick Graham from the ARC Centre for Coral Reef Studies said in a James Cook University press release.

Seventy percent of the world's coral species are considered to be "degraded." If they are to be saved from the brink of extinction serious measures are necessary.

A research team found that factors such as heavy rainfall and "controlled grazing pressure" can actually help regrow sparse vegetation.

"Normally we think of these shocks as damaging to coral reefs - but research suggests they are just as damaging to the organisms that can replace coral. In other words they may act as a circuit-breaker that allows corals to regain control of a reef," Graham said.

Healthy coral reefs are usually fairly weather resistant, but can become overcome with sea weeds when damaged.

"Weed-dominated systems are pretty resilient too and, once established, it is very hard to restore the corals," Graham said. "However a weed-dominated reef can be damaged by big storms too. Cloudy weather and seasonal changes in water temperature can also cause the weeds to die back. This dieback of weeds opens a window through which corals can re-establish."

Graham believes reducing human impacts on the reefs, such as regulating water quality, could give the coral a chance to "bounce back,"

"When it comes to saving our coral reefs, prevention is always better than cure and early action is important to slow or reverse degradation," Professor David Bellwood from the Centre and JCU, said.