Resilience of Coral

Threats to Coral
Coral reefs have grown on Earth for tens of thousands of years but more recently,  human activity and environmental changes have hindered their prosperity. Currently, one-quarter of coral reefs around the world are considered to be damaged to the extent that they cannot be restored. Another two-thirds of coral is under serious threat. There are a variety of reasons that coral faces such adversity including climate change, harmful fishing habits, thoughtless tourism, pollution, erosion, and coral mining.

Coral require lower water temperatures to survive. Thus, as the global temperature continues to rise so do the levels of coral bleaching. It is predicted that coral bleaching will remain an issue and will increase in frequency and severity in the coming years. For coral reefs that are already stressed, coral bleaching often results in the deterioration of those ecosystems. It doesn’t help that pollutants from industrial waste, sewage, and runoff invade a coral’s habitat promoting algae growth. The overgrowth of algae limits the amount of sunlight available to the coral resulting in the coral’s death. Erosion can also limit a coral’s exposure to sunlight. Sediment from the coastlines and rivers finds its way to the ocean where it rests on coral blocking the sunlight. This problem is intensified when deforestation and construction occurs and increases the amount of erosion in a smaller period of time.

Tourism can also have a negative impact on coral reefs if proper precautions are not taken. Boating, diving, snorkeling, and fishing can harm coral reefs. When people dive and snorkel they often touch reefs, stir up sediment, and collect pieces of the coral as souvenirs. Coral mining also occurs for construction materials such as ingredients for concrete mixtures. When it comes to fishing, people are often reckless. Using cyanide fishing, dynamite fishing, and bottom trawling methods are extremely destructive to coral reefs. Even when using the proper fishing techniques, it is important to avoid overfishing. Overfishing creates an imbalance in the coral reef communities. The negative impacts of overfishing can ripple past the boundaries of the coral reef as well.

Courageous Coral
Despite these setbacks, some coral are surviving and thriving. Select coral are now living in unclear waters, near the shore, even close to human populations. These coral are surviving because they have adapted and are now able to withstand levels of heat that would result in coral bleaching elsewhere. Marine ecologists from the School of Ocean Sciences at Bangor University have also noticed symbiotic microorganisms that help to support these coral in their fight for survival. This study has professionals working around the world. As of January 2018, Professor John Turner has been leading work in the Chagos Islands of the Indian Ocean while Dr. Gareth Williams works with reefs in remote sections of the Pacific Ocean. These experts are now looking for opportunities to further develop these microorganisms through bioengineering. It is possible that these advances could produce coral that is able to survive and thrive in even higher temperatures. It is hoped that these developments will provide an opportunity to save other coral reefs too. Specific types of coral also display higher levels of resiliency. For instance, brain coral is more resilient than finger coral as they have enhanced stress tolerances and are able to rebound from coral bleaching events.

There are a plethora of initiatives taking action to save coral. After facing large impacts from major coral bleaching events in 1998 and 2016, Kenyan residents of the Wasini Island are taking action by replanting damages coral reefs. These coral are grown and in nurseries where they are give the support needed to be resilient once transported to their natural habitat. These transplanted coral reefs have grown exponentially faster than originally predicted, growing more than 1.5 inches per year. They have also limited the amount of destructive fishing that occurs by restricting access to areas where coral live and enforcing a ban on blast fishing. Coral Vita is another organization using coral transplanting as a solution to support threatened reefs, but they are taking a global perspective with hopes to create a global network of land-based coral farms.  

Resilient coral usually have a strong connection to a healthy reef. These reefs may be self-seeding as they make efforts to expand. Additionally, herbivorous fish are an integral part of a coral’s health. Herbivorous fish graze on the algae that suffocates coral which allows sunlight to reach the coral. These coral may also provide a home to these sea creatures so these coral-fish relationships are truly symbiotic.

Your Support Matters
Coral reefs only cover one percent of the planet though they are home to 25 percent of marine species. Due to the importance of coral reefs, people around the globe are making efforts to support these beautiful ecosystems. A Maui community took initiative to protect algae eating fish that help to control the growth of algae on coral reefs. They created the Kahekili Herbivore Fisheries Management Area to help protect these algae-eating fish, who ultimately help coral avoid suffocation. The current results are showing new coral growth across the reef and fish population numbers are up. Coffee farmers in Puerto Rico are now transporting their farms from bare hillsides to forests to reduce the amount of agricultural runoff that negatively impacts coral reefs. By shifting to shade grown java, these groups are using the roots of trees, shrubbery, and the like to filter the runoff before it reaches the waters. These choices aim to promote a healthy immunity for coral which enhances their resiliency.

You can make a difference too! One of the easiest ways to support the betterment of coral is to avoid harming coral. When coral is left alone by humans it is capable of recovering from traumatic stress events more effectively. If you want to be a more active advocate for coral reefs, donate to organizations that are making efforts to protect and plant new coral growth. Make an effort to limit the amount of pollution you produce. This includes cutting back on lawn care products that could infiltrate runoff and ultimately end up in our oceans suffocating coral reefs. You can also contact your government representatives to voice your concerns for coral and request that they support movements that protect the valuable habitats.

SOURCES: World Wide Fund for Nature; Science Daily; Reef Resilience Network; U.S. Department of Commerce; The Nature Conservancy; News Deeply; Coral Vita