Caribbean Coral Reefs Flattened

Written by on June 14, 2009 in Marine Life
Flattened coral reefs in the Caribbean - UEA

Flattened coral reefs in the Caribbean - UEA

A disturbing new study by the University of East Anglia (UEA) and the Simon Fraser University proves the last 40 years to have been devastating for the vast majority of coral reefs in the Caribbean.   

The UEA has published  a study in which it documents the collapse of the reef structure in the Caribbean, which has serious implications for biodiversity and coastal defences the reefs provide support for a variety of marine life as well as buffer coastal regions from strong waves and storms. 

Coral reefs make up one percent of the world’s oceans and house nearly 25 percent of life in the ocean.  They are vulnerable to a variety of stressors.  A one degree rise in temperature can damage coral, it will expel its symbiotic algae resulting in coral bleaching.  If the stress is prolonged, the algae will not return, and the coral will die.  Several other factors can cause bleaching or other damage; hurricanes and predators, as well as pollution and overfishing.

Crater caused by blast fishers  -  (c) Wolcott Henry 2005/Marine Photobank

Crater caused by blast fishers - (c) Wolcott Henry 2005/Marine Photobank

500 surveys across 200 reefs in the Caribbean conducted between 1969 and 2008 found that 75 per cent of the reefs are now largely flat and uniform, having lost their complex structure, compared with 20 per cent in the 1970s.

This flattening occurred first in the late 1970s, when a widespread disease killed a large number of corals and lately as a consequence of human-induced climate change increasing sea surface temperatures, fishing methods, pollution and even sediment runoff from farms, construction and deforestation.
 
“For many organisms, the complex structure of reefs provides refuge from predators. This drastic loss of architectural complexity is clearly driving substantial declines in biodiversity, which will in turn affect coastal fishing communities” said Lorenzo Alvarez-Filip, lead researcher of UEA’s School of Biological Sciences. 

 

Coral degradation - Sand dredged from offshore and deposited on land to replenish a beach washed back to sea and covered these reefs in Palm Beach, FL  -  Photo by Steve Spring Palm Beach County Reef Rescue/Marine Photobank

Coral degradation - Sand dredged from offshore and deposited on land to replenish a beach washed back to sea and covered these reefs in Palm Beach, FL - Photo by Steve Spring Palm Beach County Reef Rescue/Marine Photobank

“The loss of structure also vastly reduces the Caribbean’s natural coastal defences, significantly increasing the risk of coastal erosion and flooding.”
 
Reefs grow best in clear waters that are poor in nutrients.  They can grow up to 3.9 inches (10 centimeters) per year in the following optimal conditions:
 ○ Ample light
 ○ Clear water
 ○ Temperatures between 73.4 degrees Fahrenheit and 84.2 degrees Fahrenheit (23 degrees Celsius and 29 degrees Celsius)

 

A well-developed reef can take thousands of years to form.  [source: NOAA].

 

Scientists and policy-makers concerned with maintaining reef ecosystems and the security and well-being of Caribbean coastal communities are already working on reversing the declines in the reef architecture.

The study was published on June 10 in Proceedings of the Royal Society B:  ‘Flattening of Caribbean coral reefs: region-wide declines in architectural complexity’  by L Alvarez-Filip (UEA), N Dulvy (Simon Fraser University), J Gill (UEA), I M Côté (Simon Fraser University) and A Watkinson (UEA)

Copyright ©  2009 by Marine Science Today, a publication of OceanLines LLC

About the Author

About the Author: Celia is Director of Business Operations for OceanLines LLC and is a frequent contributor to both OceanLines and Marine Science Today. She is a certified diver and her favorite topic is marine biology, especially stories about whales. .

Subscribe

If you enjoyed this article, subscribe now to receive more just like it.

Subscribe via RSS Feed Find MST on Instagram Connect with MST on Google Plus

Comments are closed.

Top