What effect do hurricanes have on coral reefs?



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What effect do hurricanes have on coral reefs?

In meteorology, a tropical cyclone is a stormy system, or type of cyclone, originating in tropical or subtropical waters of the planet and characterized by a hot-core low pressure center or vortex and numerous storm fronts (squall lines), typically arranged in spiraling and rotating around a well-defined center, which produce strong winds and heavy rainfall in the areas affected by their passage.

On the other hand, an Atlantic hurricane is a tropical cyclone that forms in the Atlantic Ocean, usually in the Northern Hemisphere, in summer or autumn, with sustained winds for one minute at 119 km / h (64 knots / 32.9 m / s).

When referring to hurricanes, "Atlantic" generally refers to the entire Atlantic basin which includes the North Atlantic Ocean, the Caribbean Sea and the Gulf of Mexico. Most tropical storms and hurricanes occur between 1 June and 30 November.

The US National Hurricane Center monitors the basin and publishes reports, observing and warning of tropical weather systems forming in the Atlantic Basin. The study: Hurricane impacts on a coral reef soundscape, published on the PloS one, said about this specific topic: "Soundscape ecology is an emerging field in both terrestrial and aquatic ecosystems, and provides a powerful approach for assessing habitat quality and the ecological response of sound-producing species to natural and anthropogenic perturbations.

Little is known of how underwater soundscapes respond during and after severe episodic disturbances, such as hurricanes. This study addresses the impacts of Hurricane Irma on the coral reef soundscape at two spur-and-groove fore-reef sites within the Florida Keys USA, using passive acoustic data collected before and during the storm at Western Dry Rocks (WDR) and before, during and after the storm at Eastern Sambo (ESB).

As the storm passed, the cumulative acoustic exposure near the seabed at these sites was comparable to a small vessel operating continuously overhead for 1-2 weeks. Before the storm, sound pressure levels (SPLs ) showed a distinct pattern of low frequency diel variation and increased high frequency sound during crepuscular periods.

The low frequency band was partitioned in two groups representative of soniferous reef fish, whereas the high frequency band represented snapping shrimp sound production. Daily daytime patterns in low-frequency sound production largely persisted in the weeks following the hurricane.

Crepuscular sound production by snapping shrimp was maintained post-hurricane with only a small shift (~ 1.5dB) in the level of daytime vs nighttime sound production for this high frequency band. This study suggests that on short time scales, temporal patterns in the coral reef soundscape were relatively resilient to acoustic energy exposure during the storm, as well as changes in the benthic habitat and environmental conditions resulting from hurricane damage. "