Press Release September 28, 2005

Critical Bleaching Event Impacts Caribbean Corals

Mass Mortality of Corals Possible

Robert Ginsberg, University of Miami Rosentheil School of Marine and Atmospheric Research

Photo of normal coral tentacle showing single-celled algae in the tissue. These algae are expelled during coral bleaching events, leaving the animal white in appearance.

The Caribbean's beautiful coral reefs are now experiencing a very serious coral bleaching event. This is very bad news. The coral reef ecosystem plays a significant role in maintaining the atmosphere of our planet as well as sustaining the livelihoods of millions of people in the Caribbean.

Corals bleach in response to stress. These animals derive their color from single celled algae that live inside the animals' tissue. The algae act as tiny solar panels, collecting and converting sunlight into energy the coral can use to power its reef building activity.

When the corals are subject to stress from excessive heat, water pollution or both, these algae are expelled. This leaves the corals white in appearance. The corals can live for a few weeks in this "bleached" state. If the stress to the corals is removed, (water cools, pollutants removed) then the animals might recover. If not…they die.

The weekend of September 23rd, 24th and 25,th Dr. Edwin Hernández Delgado of the University of Puerto Rico's Coral Reef Research Group and CORALations, a non profit conservation organization took on the heart-wrenching task of documenting severe bleaching on the Island of Culebra.

This is a record-breaking total of 63 species for a single bleaching event in the Caribbean. Some corals are already dead. Some species of corals that are bleaching have never before been seen to bleach, including 8 species of beautiful sea rods, a flexible coral.

Our last severe bleaching event occurred in another hot summer, 1998 just before hurricane Georges. Most of Culebra's reefs recovered to their pre-bleaching state of health. However, the concern today is that we may be witnessing a massive die-off. Reports from Vieques, Barbados and many other Caribbean islands are grim. Bleaching- associated mortality has already been documented in the more contaminated waters off of the east coast of Puerto Rico by Dr. Hernández and his colleague, Prof. Carlos Toledo, in collaboration with divers from Department of Natural and Environmental Resources. The corals of the Netherlands Antilles, where waters have remained cooler, are to date unaffected.

You may have heard talk of warmer sea surface temperatures being responsible for the size and strength of catastrophic hurricanes this year. Since April, NE Caribbean islands have seen higher than normal sea surface temperatures…sustained. This has had a dampening effect on the trade winds which circulate and mix the surface waters, and usually aid in keeping the sea a bit cooler in the summer. In turn, the warmer sea surface temperatures further dampen the trade winds. This has lead to a feedback loop of doldrum-like conditions proving lethal for corals in our region. The Caribbean sits like a bowl of soup in the sun, getting hotter and hotter. A posting to NOAA's coral reef electronic list serve on the 22nd of September by Scott Stripling, from the U.S. Weather Service, indicated that "these stagnant mixing conditions [in the Caribbean] are likely to persist through October, at the least."

CORALations Artist Rendering: Caribbean Basin September 2005

What can we do besides pray? We can give our reefs a well deserved break. Stop the mud from land clearing and construction projects from pouring into our coastal waters. This is "fertilizing" aggressive algae and toxic cyanobacteria over-growing and infecting corals already stressed by the bleaching. Demand adequate waste water treatment and put an end to the discharge of toxic industrial waste and rum slop on our reefs daily. After years of this abuse, it appears government agencies are unable or unwilling to stop it. In U.S. territories graced with coral reefs, the implementation of the 30-year-old Clean Water Act is our conservation opportunity. It is up to the people to take action and do everything they can locally to give our reefs a break. There may be no second chance on this one.


Articles on Coral Bleaching:

About CORALations | About Coral Reefs | Ocean Conservation Youth Corps
 Sea Turtles |
Coral Reef Restoration

CORALations, Inc.
P.O. Box 750
Culebra, PR 00775
787-556-6234 / Fax 530-618-4605
1-877-77-CORAL 1-877-77(2-6725)