Coral Reefs in Honduras: Status after Hurricane Mitch [En Español]

In response to the devastation wrought by Hurricane Mitch in Honduras, the USGS performed a study to determine the impact the storm had on the coral reef systems of Cayos Cochinos and Roatán, Honduras.

Figure 1. Satellite image of Hurricane Mitch on October 27, 1998 showing a very well developed central eye. Mitch was positioned just to the northeast of Guanaja, Honduras. Image provided by NOAA.

Reef corals from around the world were severely affected from bleaching by the large El Niño event in 1997-1998. Mass bleaching events occur when prolonged high sea-surface temperatures stress corals, causing the expulsion of symbiotic zooxanthellae (plant-like organisms living within the coral tissue). Extended periods of bleaching may lead to an increase in coral mortality. It is estimated that ~16% of the world's corals were destroyed from this single bleaching event in 1998 (Wilkinson, 2000). Unfortunately, coral reef environments along the north coast of Honduras were about to face additional problems. On October 25, 1998, Hurricane Mitch (Figure 1) had formed into the fourth strongest Atlantic hurricane on record; a category 5 hurricane with 180+ mph wind speed and estimated wave heights of 50 feet. Mitch turned out to be the deadliest hurricane since the great hurricane of 1780.

Figure 2. Index map (top) showing location of Cayos Cochinos and Roatán, Honduras and path of Hurricane Mitch. Aerial photograph of Cayos Cochinos (bottom) showing location of monitoring stations (red dots) and distribution of fringing coral reefs. Click on the image for a larger version.

Mitch lost energy and became a category 4 hurricane on October 27 as it began to interact with the mountainous terrain on the Honduras mainland. Mitch passed over Roatán, Guanaja, and Cayos Cochinos on October 27 & 28 (Figure 2) with 130-mph winds and caused severe damage to buildings and onshore habitats. Mitch dropped over 6 ft of rain on the mainland causing severe flooding, landslides, and mudflows. In its wake, Mitch left about 11,000 people dead and 2 million people homeless throughout the countries of Honduras, Nicaragua, El Salvador, and Guatemala. In response to this devastation, funding for the project was provided through the U.S. Agency for International Development (USAID), from a supplemental Congressional budget allocation to provide assistance to Mitch-affected countries. USAID also earmarked funds for use by the U.S. Geological Survey (USGS) to establish a network of early detection systems (stream gauges, maps of landslide-prone areas, etc.), collection of water-quality information, and assessment of post-Mitch damage to coastal resources such as coral reefs, seagrass beds, and mangrove forests. This study focuses on the impact of Mitch on the coral reef systems of Cayos Cochinos and Roatán, Honduras.