Coral bleaching and how you can play your part in saving our reefs

Our crew and photographers have been keeping a watchful eye on the corals in the bay to monitor for any changes in the health of the reef. As coral bleaching events are becoming more frequent on coral reefs worldwide it is important that monitoring programs are occurring to help scientists understand exactly what is going on.

What is coral bleaching?

Most corals get their stunning colours from a marine algae that lives in their tissues known as zooxanthellae. The coral and the zooxanthellae live in a mutualistic relationship (each helps the other to survive) with the algae providing the coral with around 90% of its food by creating sugars through photosynthesis, giving them the energy to grow. In return, the zooxanthellae receive protection.

Coral bleaching is associated with a variety of stressors in their environment including, changes in salinity, pollutantants, increased sediment and runoff into the water, and potentially the most common being a rise in seawater temperature. These changes in condition create the corals to become stressed and expel the zooxanthellae out from their tissues. Most corals that become bleached will starve and become more susceptible to diseases and without the zooxanthellae the corals lose their colours, turning ghostly white.

Are all corals dead once they are bleached?

No, not all corals are dead if they are bleached. Corals can survive a bleaching event if conditions quickly return to a normal state. However, if unfavourable conditions are prolonged, the zooxanthellae is less likely to recolonize with the coral and will eventually lead to the death of the coral. The corals that do survive a bleaching will be more prone to diseases and their energy sources are depleted causing them to potentially not reproduce for over 2 years. Across the world we are witnessing these events more frequently with little to no time for these corals to recover.

Coral reefs are home to 25% of the world's marine life, often referred to as the rainforests of the sea. If bleaching events become a frequent occurrence and the corals do not have time to recover from a bleaching, it will have detrimental effects on the reefs ecosystems. Not only will it have a drastic effect on our oceans, but also food security for a large population of people worldwide.

Monitoring corals for signs of bleaching

As there is dramatic colour loss associated with bleaching events, it can show clear indications of the health of the corals. There aren't enough scientists in the world to monitor all our reef systems, the ningaloo alone stretches a whopping 260km, so that's where we come in to assist.

Along with many other citizen scientists across the globe, the crew go out and conduct random coral surveys collecting the location, time and temperature of the water. With the use of Coal Watch monitoring chats, crew visit a few patches of our reef frequently to monitor for any signs of coral bleaching. Without touching the coral, the slates are rotated until there is a colour match. The darkest and the lightest area of the coral along with the type of coral are recorded. This is repeated for at least 20 corals. The recorded data then is uploaded onto the coralwatch.org website. This data is used for scientific research and to aid in ongoing and future monitoring.

If you would like to learn more about coral watch and how you can assist in the health and monitoring of our coral reefs visit www.coralwatch.org

Here are some ways you can help from home:

Every little bit counts, even if you do not live near the ocean a little goes a long way! As climate change is thought to be one of the main threats causing coral bleaching, a great way to help our corals is to strive to reduce your emissions.

When you visit a coral reef, practise responsible snorkelling and diving. Take the time to anchor vessels in areas with a sandy bottom rather than on top of corals. Avoid touching corals and kicking them with your fins as they are delicate animals.

Apply reef safe sunscreen. In sunscreens there are certain ingredients that are harmful to our corals including Oxybenzone and Octinoxate. Swap these harmful sunscreens to a more reef safe product such as SunButter.. All crew on our boats use reef safe sunscreen which is also available for guests.

A simple way to help is to reduce your single use plastic. Plastics are quickly finding their ways into the ocean, causing harm