Can we save the Great Barrier Reef?

A recent helicopter flyover suggested Australia's Great Barrier Reef is 90 percent bleached, damaged by tourists and a rough El Niño year.

It's been a rough year for reefs, and the Great Barrier Reef near Australia is no exception.

The coral reefs need attention in the next few decades, and the longer the reefs go untreated, the less effective – and more expensive – such work is likely to be.

"They’re not going to disappear tomorrow, but the more we lose the harder it is to restore it," Chris Langdon, a marine biologist at the University of Miami, tells The Christian Science Monitor. "Actions now will be less drastic than what could be required later." 

A helicopter trip by Australia's National Coral Bleaching Taskforce in late March showed more than 90 percent of coral were bleaching, including the Great Barrier Reef. 

“We could see extensive bleaching even among the most robust ‘massive’ corals,” said James Kerry, project manager of the National Coral Bleaching Taskforce, in a press release. “The fact that these hardy species have also turned white shows just how severe summer conditions have become." 

Coral turns pale or "bleaches" when dealing with stress, whether from rough handling by tourists or just too-warm water. This year, El Niño's naturally occurring Pacific warming pattern has hurt the weak and damaged coral further.

"This is shaping up to be one of the worst years for bleaching in a long time," Prof. Langdon says. 

The Great Barrier Reef, one of Earth’s great natural wonders, is part of the "coral triangle," what scientists call the environment best suited for coral to thrive and flourish. Although most bleached coral does not die at once, the extensive bleaching in what has been the world's healthiest reefs concerns scientists.

Scientists from Australia's marine science agency reported on Sunday that the government's current reef-saving plan will not reach its 2050 targets and that the current plan to slow pollution from the mainland is insufficient, the Guardian reported. They recommend changing the use of fertilizer, as it flows from the crops into the ocean.

Carbon dioxide pollution can doubly weaken coral reefs already stressed by warm water. Coral reefs – creatures that were widely believed to be plants until the 18th century – must consume calcium to build and rebuild their vast structures, the Monitor's Eva Botkin-Kowacki reported in February.

When the acidity of the ocean water changes, as it does when high volumes of carbon dioxide dissolve into it, the coral’s ability to consume nutrients changes – this time, for the worse. Coral provides a bellwether for ocean health generally.

"This is a warning sign," Langdon says. "It’s maybe one of the more delicate ecosystems out there."

The coral's health is connected to that of the ocean ecosystem generally. An estimated 25 percent of the ocean's fish spend some part of their lives in a coral reef, so the consequences of a damaged reef can ripple throughout the ocean ecosystem, including everyone who relies on sea creatures for food and employment.

Marine biologists have advocated creating marine protected areas where fishing is prohibited, and both President Barack Obama and former President George W. Bush have done so. Because they eat algae, coral's natural competitor, flourishing fish benefit coral indirectly. 

The end of El Nino will naturally reduce the stress on the coral reefs, but another major stressor is pollution. Although carbon dioxide is an ongoing global project, Denmark and China have successfully impacted local reefs by changing the agricultural and cropping use of land, the Guardian reported. In a study published in March, Langdon suggests more of these multi-variable, regional approaches help.

"The idea is reducing all the forms of stress on the reef that we have control over," Langdon says.