Coral reefs are more than “just a pretty face.”

Why should we care about coral reefs? If you don’t often interact with coral reefs, or even if you do, you might have trouble answering that question. You probably know that coal reefs are beautiful marine ecosystems. But they only really matter to people who want to visit them, right? Wrong. Not only do coral reefs support eco-tourism and recreational industries, but they are also important habitat for many fisheries. NOAA estimated that coral reef fisheries in the US are worth over $100 million. Coral reefs are some of the most diverse ecosystems on the planet. This makes them fascinating places to visit, but also adds to their value as many important drugs are developed from coral reef inhabitants. Overall, coral reefs provide an estimated $375 billion worth of “goods and services” to humans and a recent study reveals how coral reefs might also be important for our safety.

New study: Coral reefs reduce wave energy and coastal flood risks

Researchers in this study were interested in how coral reefs protected coastlines from wave energy, and compared this benefit to that of artificial shoreline protection structures like seawalls or breakwaters. They found that coral reefs reduce wave energy by an average of 97% and reduce wave height by 84% on average. Artificial breakwaters only reduce wave height by 30-70%. Additionally, the construction of artificial breakwaters ranges from $456-188,817 (median cost: $19,791 ) per meter while the cost of coral reef restoration was significantly lower (median project cost: $1,290 per meter). So, healthy coral reefs can reduce wave energy more than artificial structures and can be restored for lower costs.

What does this mean for people?

This study found that the amount of energy and wave height reduced by coral reefs increased as the intensity of the wave increased, such as during hurricanes. For example, waves during Hurricane Wilma in 2005 reached 13 meters in height, but the Meso-American reef reduced wave heights by 99%. This reduction is extremely important as an estimated 2.6 million people have been killed by coastal flooding, particularly storm surge, in the past 200 years.  Last year, almost all of the casualties and economic losses from Hurricane Sandy and Typhoon Haiyan were due to water and waves, not wind, according to the World Meteorological Organization.

The figure below depicts the 197 million people that could benefit from risk reduction by coral reefs, according to this study. Indonesian would have the largest number of people benefit from coral reef-associated risk reduction, followed by India, the Philippines, and China. The United States is listed as 7th on the list.

The number of people who may receive risk reduction benefits from reefs by country. http://www.nature.com/ncomms/2014/140513/ncomms4794/fig_tab/ncomms4794_F6.html

Coral reefs are very beautiful and fun to visit on vacation, but they also provide us with many goods and services that are important to tourism, fisheries, medicine, and even our safety. It is critical that we conserve and restore these ecosystems in order to continue receiving these benefits in the future.