The Great Barrier Reef

By Alison M. Brown

Coral reefs are some of the ocean’s most spectacular attractions. Their vibrant, glistening colors are hard to miss, especially with the right kind of the sunlight. But coral reefs aren’t just aesthetically pleasing, they also provide unique habitats for 25 percent of all marine life and act as a primary source of food and income for over 500 million people.

Coral reefs currently face a number of risks, but the one posing the greatest threat to their long-term survival is climate change. Even though we’ve only experienced a global temperature increase of one degree Celsius, the impacts so far have been devastating. 

Ocean researchers estimate that approximately 75 percent of coral reefs are considered threatened or deceased because they are highly sensitive to changes in ocean chemistry. When we burn fossil fuels and gases like carbon are released into the atmosphere, our oceans absorb it, just like trees. Carbon emissions also impact global temperatures because they amplify a phenomenon called the greenhouse effect. Greenhouse gases in the atmosphere act as a blanket for the earth, keeping temperatures within a habitable range. But as we add more of these gases to the atmosphere, global temperatures rise, which leads to climate instability. 

Coral bleaching

The reason why reefs are so sensitive to these global changes is because of a symbiotic algae that lives on coral structures. The algae is known to scientists as zooxanthellae (zo-zan-THELL-ee) and provides corals with nutrition and their vibrant colors. When the ocean starts to warm, these highly sensitive algaes expel from the coral, causing their skeletal systems to become bleached and vulnerable. This phenomenon is called ‘coral bleaching’ and it’s currently happening to reefs all over the world.

Can other coral reefs survive?

While the future of the Great Barrier Reef is uncertain, not all hope is lost for other reefs around the world. Recent research from the country of Palau suggests there are some types of coral that can adapt quite easily to changes in ocean chemistry and warmer waters. Palau is hotbed of biodiversity which offers scientists a lot of clues for reef adaption strategies. This includes identifying specific traits that adaptive corals carry, which is similar to how researchers are looking for human traits that are resistant to cancer.

Another organization, the Coral Reef Alliance (CORAL), has also launched program called “Adaptive Reefscapes” that studies how corals can adapt to changing conditions. The program combines cutting-edge science that focuses on coral adaptation within well-connected and diverse networks of healthy reefs. The strategy has a strong focus on diversity, meaning the greater the ecological diversity of the reef, the greater its chance of adapting to a changing environment over time. 

While the future of the Great Barrier Reef is uncertain, not all hope is lost for other reefs around the world. Recent research from the country of Palau suggests there are some types of coral that can adapt quite easily to changes in ocean chemistry and warmer waters. Palau is hotbed of biodiversity which offers scientists a lot of clues for reef adaption strategies. This includes identifying specific traits that adaptive corals carry, which is similar to how researchers are looking for human traits that are resistant to cancer.

Another organization, the Coral Reef Alliance (CORAL), has also launched program called “Adaptive Reefscapes” that studies how corals can adapt to changing conditions. The program combines cutting-edge science that focuses on coral adaptation within well-connected and diverse networks of healthy reefs. The strategy has a strong focus on diversity, meaning the greater the ecological diversity of the reef, the greater its chance of adapting to a changing environment over time. 

This is important because these special corals can be used to help regrow reefs in other regions of decline. Researchers believe that with the help of local and international communities, we can support the long-term viability of these reefs for generations to come. Nature has an interesting way of being able to adapt to environmental changes, only time will tell if our reefs can adapt fast enough.