10/14/2024
Have you ever wondered what happens on a coral reef during a hurricane? Hurricanes are a natural part of the seasonal cycle. The passage of a hurricane can sometimes be a great benefit to coral reefs...except when it isn’t.
Coral reefs serve as buffers for coastal areas around the world such as Dry Tortugas and the Florida Keys. They absorb up to 97% of wave energy which can reduce erosion and provide critical protection from storms and floods.
The peak of hurricane season aligns with the spawning season for some types of coral. Hurricanes can help to disperse coral larvae farther and wider than would happen without the storm. This can help to promote genetic diversity and the growth of new reef colonies. This could be beneficial if that particular type of coral is disease-adapted or better adapted to warmer ocean temperatures. Coral larvae is not the only thing that can be spread over greater distances during a hurricane, however. Diseases, such as stony coral tissue loss disease, are also dispersed wider with the passage of a storm.
Some corals, like the staghorn coral pictured here, are able to reproduce by a process known as fragmentation, when pieces of the coral structure break off and settle in a new location. In this way, hurricanes can help to establish new colonies. Massive storms, however, can cause extreme devastation and cause entire colonies to wash away.
Storms can bring large upwellings of cooler water from deeper areas of the ocean which can help to reduce the thermal stress on corals that often happens in the summer months. However, large amounts of freshwater can disturb corals, as can the silt that settles on a reef after the storm passes.
As you can see the effects are complicated! We won't immediately know what the impact of Hurricane Milton is on the reef at Dry Tortugas until possibly some months after the storm.
NPS Photo by the Submerged Resources Center
