Global Warming Causes Coral Babies to Stay at Their Home Reef

As our climate changes and oceans warm, coral reefs are feeling the impacts. Now, researchers have discovered that the warmer temperatures are causing coral larvae to stay at "home" rather than venturing abroad on ocean currents. This could cause large reef systems to be less interconnected and potentially more vulnerable.

"We found that at higher temperatures more coral larvae will tend to stay on their birth reef," said Joana Figueiredo, one of the researchers, in a news release. "This is good news in an otherwise cloudy picture for isolated reefs, because in the future they will be able to retain more of their own larvae and recover faster from severe storms or bleaching events."

Warmer ocean temperatures are known to impact coral reefs in a variety of ways. They can stress the corals and cause them to release their zooxanthellae, which aid in photosynthesis. These bleaching events can result in giant swathes of corals dying off. In addition, the warmer temperatures can aid in the spread of coral diseases.

While corals may be able to recover more quickly from these problems due to larvae sticking nearby, this may also reduce the interconnectivity of reefs.

"The loss of connectivity can make reef systems such as the Great Barrier Reef more vulnerable," said Sean Connolly, one of the researchers, in a news release. "So interconnected reef systems that depend on the recruitment of coral larvae may take more time to recover after a disturbance, such as a cyclone, because fewer larvae will disperse from other reefs to the disturbed reef."

The findings reveal that global warming will cause the layout of reefs to change. As ocean water temperatures continue to rise, connectivity will be altered. This, in turn, could impact the health of reefs. The findings also highlight the importance of taking action to curtail climate change.

The findings are published in the journal Nature Climate Change.