Marine Conservation - Live From Mexico - Part 3
By Rose Little - Wildlife & Welfare Researcher volunteering with Global Vision International (GVI) in Puerto Morelos, Mexico
Corals In The Reef
When disaster struck the Amazon rainforest, fire ripped through the landscape and the media told us all “the lungs of the earth are burning”. Although there is no doubt that this was a terrible event and a direct effect of the climate crisis, it brings into light the severe human error of ignoring our marine environment. The coral reef systems around the world provide our planet with two thirds of the oxygen we breathe. They also have the amazing ability to sequester millions of tonnes of carbon dioxide.
Coral reefs cover less than 1% of the ocean floor however they are essential for the survival of our planet. 25% of marine life relies on coral reefs for reproduction, hunting and sanctuary. Alongside this the coral reefs, sea grasses and mangroves play an important role to protect the land from coastal erosion and extreme weather events. In essence without a healthy marine system our home will not survive the anthropogenic destruction.
An example of sick and healthy coral together.
The reef systems are dying. They are under threat from rising ocean temperature, ocean acidification, coral diseases, damage from boats, anchors and divers. No matter how far away you live from the sea your everyday actions are impacting the oceans. Driving to work releases greenhouse gases that are warming our planet. Burning fossil fuels to warm our houses is increasing the acidity of the ocean through the absorption of carbon dioxide. Littering is leading to the formation of plastic islands (discussed in last week’s blog). Our everyday actions are creating chain reactions that are disrupting the balance of our marine and terrestrial ecosystems. We all need to start making huge changes in our lifestyles if we want to protect our ocean.
Our ocean helps to control global temperatures and absorbs vast quantities of carbon dioxide. As the temperature and carbon dioxide levels increase the ocean temperature is rising rapidly and becoming more acidic. This is stressing corals and leading to an increased prevalence of coral bleaching events.
Corals are small animals which live symbiotically with zooxanthellae algae. The algae give the corals their colour and provide them with essential food by converting the sunlight’s energy into usable energy (glucose). When corals get stressed by ocean acidification and warmer temperatures, they release the zooxanthellae algae and so lose their primary food source. However, as the ocean temperature continues to rise the corals are bleaching more severely and more frequently. Corals are starving to death. Corals can survive bleaching events if favourable conditions return and they will reabsorb the algae and thrive. It is therefore not too late to change our lifestyles, combat climate change and save the reefs.
Here at GVI we partake in CoralWatch surveys. CoralWatch was set up by the University of Queensland to collect data on coral bleaching. They collate data from all over the world through citizen science programs in around 80 countries. They look at the prevalence and severity of bleaching events and which corals are affected more. With a torch and the CoralWatch slate we randomly select 20 corals in a dive and assess the colour of the organism. We select the darkest and lightest sections of the coral and report the information to CoralWatch. With this information the University of Queensland can gain a better understanding of coral bleaching and climate change and affect the decisions of policy makers.
Rose monitoring juvenile fish who are indicators of reef health.
Alongside bleaching there are many diseases which affect corals. Here in the Caribbean, there is one that is of the greatest concern. Stony Coral Tissue Loss Disease (SCTLD) is tearing through the reef at an alarming rate. SCTLD first appeared in Florida in 2014. The disease has now spread across the Caribbean destroying over 20 species of stony coral, killing them within weeks or months of becoming infected. Characteristics of SCTLD are that sick colonies present with multiple lesions and die quickly. It is a poorly studied disease, and the causal agent is unknown. The disease is thought to have spread by water movement however its spread is against prevailing currents. It is therefore possible that SCTLD is spread through ballast water, biofilms and dive gear. Divers are advised to disinfect their gear especially if moving around.
Stony Coral Tissue Loss Disease.
GVI are collecting data for AGRRA monitoring SCTLD, other coral diseases and bleaching. We are monitoring the prevalence of diseases and bleaching events in the Mesoamerican barrier reef recording the species that are being affected the most. It is important to understand the prevalence of each disease on the reef so that AGRRA can affect the decisions of policy makers and perform important research on finding a cure for SCTLD and other coral diseases. Unfortunately, we have yet to gain a true understanding of our marine environment and so little is known about coral health.
Many organisations are also trying to protect the reef through microfragmentation projects. Our partners at GVI, CRIAP, are one such organisation. With our assistance the coral laboratory grows healthy coral populations to replant on the reef. They also monitor and collect spawn from coral spawning events. Microfragmentation and coral reef restoration projects are vital to marine conservation as the reef continues to die at an alarming rate. By having a healthy, genetically diverse coral population in coral laboratories we have a chance of restoring coral reefs. In some coral laboratories scientists are studying the effect of increased temperatures and acidity on corals, developing more resistant corals. Recent studies have found stony corals contain a mixture of biominerals and proteins which resemble human bones. This might aid them to withstand the effects of climate change.
Everyone has a responsibility to protect the marine environments by ensuring they disinfect all equipment if moving oceans to prevent the spread of disease, to not wear sunscreen in the water to prevent the release of oxybenzone chemicals in the water and to reduce their carbon footprint to battle climate change. Despite the doom and gloom that surrounds coral reef health, there is hope.
Please click the link below to visit our Environmental Calendar. Each month we focus on a new environmental topic and look in to how we can all help to improve the world we live in.
