Climate change has caused significant damage to coral reefs. These reefs are extremely important as they provide food and shelter for a large diversity of fish. Some fish species are endemic to specific reefs, making their entire existence threatened when a reef is threatened. A recent study from researchers at the University of Lancaster may have found some good news about coral reef damage.
Climate change can cause the ocean’s temperature to increase as well as become more acidic. Both of these factors can threaten a coral reef’s wellbeing, and result in coral bleaching. Coral bleaching happens when the corals expel the living algae from inside their tissues, forcing the corals to turn white. As the algae are essential for coral survival, corals and coral reefs can become more susceptible to disease and starvation without the algae. This is why coral bleaching tends to be such a catastrophic event, as it forces fish to find new shelters, and. permanently changes the local ecosystem. This can also negatively impact local fishermen who use the reefs for their livelihoods.
In a 2022 paper published in One Earth, the team looked at 20 years of coral reef data from Seychelles to track the nutrient values in the area. They analyzed the nutrient contents of 43 different tropical fish species from the area. Combining their results with nutrient data from before and after the bleaching, the team found very similar levels of iron, selenium, and zinc in the fish. This suggested that these fragile ecosystems were more resilient to climate change than expected.
The researchers found that the bleaching event caused the deaths of 99 % of the coral in the reef. But in later years, the team saw that macroalgae, like Sargassum seaweeds, now dominated the landscape. As these seaweeds contained high amounts of minerals, the researchers believed that the seaweeds were key to helping to keep a healthy amount of nutrients available for fish. According to team leader Dr. James Robinson: “We found that some micronutrient-rich reef species become more abundant after coral bleaching, enabling fisheries to supply nutritious food despite climate change impacts.”
Outlook Coral Reefs Drive food
As many people globally rely on coral reefs not only for their livelihood but for food as well, the nutrition of these reefs is important. Co-author Dr. Christina Hicks explained: “Fish are now recognized as crucial to alleviating malnutrition, particularly in the tropics where diets can lack up to 50% of the micronutrients needed for healthy growth.” This study offers an optimistic thought to climate change, suggesting that coral reefs may be able to adapt to the warming temperatures. This good news not only impacts those who live around reefs, but the global seafood and tourism industry, showing coral reefs have a greater impact on our society.
Kenna Castleberry is a staff writer at the Debrief and the Science Communicator at JILA (a partnership between the University of Colorado Boulder and NIST). She focuses on deep tech, the metaverse, and quantum technology. You can find more of her work at her website: https://kennacastleberry.com/