USAID/USGS/Honduras Hurricane Mitch Program: Coral Reef Health in the Bay Islands of Honduras
|
Don Hickey shooting video footage of a healthy reef in Roat‡n Marine Reserve, Honduras.
|
Our fifth and probably final visit to the Bay Islands of Honduras occurred from November 9 to 21. Don Hickey
and Chris Reich spent 12 days visiting three of the four Bay Islands (Roat‡n, Cayos Cochinos, and Guanaja).
The final site visit was scheduled because the USAID/USGS Hurricane Mitch Program came to a close on
December 31. The program was created to provide information in support of hazard mitigation and reconstruction
after Hurricane Mitcha Category 5 hurricane and one of the most destructive ever recorded in the Western
Hemispherestruck Central America in 1998. Our part of the program focuses on coral-reef health in the Bay
Islands. The results from all projects in the program will be placed on a clearinghouse Web site maintained by the
EROS data center (Sioux Falls, SD). The Web site contains information on projects that range from landslide
hazards and mapping (LIDAR surveys), stream gauging, and flood-hazard mapping to impacts on such coastal
environments as mangroves, seagrasses, and coral reefs.
Cayos Cochinos, which is located on the continental shelf approximately 9 miles (14.5 km) off the north coast
of Honduras, is not a popular destination for tourists. Roat‡n and Guanaja, which are surrounded by deep water
about 35 mi (56 km) north of Honduras, are popular with international tourists interested in scuba diving. The
coral reefs around Cayos Cochinos are heavily impacted by what is taking place on the mainland. Runoff carries
freshwater, sediment, pollution, and contamination to this region. Mainland runoff is generally not a problem for
Roat‡n and Guanaja.
Honduras received its share of hurricane activity during the 2001 season, though nothing to compare with
Hurricane Mitch. Hurricane Ir’s (early October) skirted the northern fringes of the Bay Islands, producing some
rain and moderate winds out of the north but otherwise causing no widespread damage. Hurricane Michelle
(late October), however, dropped copious amounts of rainfall on the mainland and throughout the Bay Islands.
It also caused extensive land erosion to the sand islands around Cayos Cochinos and may have caused some
physical damage (breakage) to branching corals, as was documented at our sites. Mainland river discharge
carried garbage, large tree stumps, and logs out to the islands. Rainfall during both hurricanes was recorded
at our two sites (Roat‡n and Cayos Cochinos), where the recording instruments are housed in 5 m of water
(see graph below). Salinity, temperature, and photosynthetically active radiation (PAR) are recorded at 10-minute
intervals. It is apparent from the data that this region is well into its rainy season and that there is sufficient
oceanic mixing to get freshwater spikes at 5-m water depths out on the reef crest.
Salinity data (upper data set, red) and photosynthetically active radiation (PAR) data (lower data set, blue)
at Pelican Point in Cayos Cochinos, Honduras, showing onset of rainy season punctuated by Hurricanes Ir’s
and Michelle (a tropical storm while over Honduras). Instrument is located in a water depth of 5 m. PAR
decreases with higher influx of freshwater, which is linked to cloud cover and degradation in water quality.
There was also some growth on the PAR sensor that led to a slow decline in the PAR value.
[larger version 45KB]
|
Other accomplishments and observations:
Water quality (that is, visibility) was poor at all three sites (Roat‡n, Cayos Cochinos, and Guanaja),
most likely as a result of all the rain they have been receiving.
Corals throughout the Bay Islands were infected with black-band disease in 1999, but since then very
little black-band disease has been observed.
Coral reefs at Roat‡n (see underwater photograph) appear to be the healthiest (low occurrence of
diseases, moderate algal cover, higher percentage of coral cover, and highest biodiversity).
Encrusting sponges and tunicates were still present at all sites.
Bleaching events are observed periodically, but they have not decimated these reefs as in other
regions around the Caribbean.
Overfishing has historically been a problem for the Bay Islands, but now both Cayos Cochinos and
Roat‡n have designated marine reserves that prohibit most fishing.
|
Impromptu discussion with Lighthouse Christian Academy school children on the island of Guanaja, Honduras.
Don Hickey explains to the children why we study reefs, why they are important, and what happened to the reefs
during Hurricane Mitch, while they take turns watching video footage shot earlier in the trip.
|
Underwater still photography and digital video recordings were utilized in documenting the status
of the coral-reef ecosystem at a particular period of time. Time-series archives of specific reefs will assist us
in documenting the decline or improvement of those reefs affected by anthropogenic stresses and (or)
natural environmental perturbations.
On the last full day of our field trip, we were invited to a local school on Guanaja to explain to the students what
it was we were doing and why (see photograph). The students, ages 6 to 12, listened patiently to explanations of
how corals grow, the differences between healthy and failing reefs, the biodiversity associated with coral reefs,
and the impacts and recovery process due to such extreme weather conditions as hurricanes. During the
PowerPoint presentation, the students also had an opportunity to view an underwater video of the local coral-reef
environment recorded earlier in the week. Finally, the students were allowed to ask questions. It is amazing
sometimes what the curious minds of children ponder.
|
|
Dec. 2001 / Jan. 2002
in this issue:
cover story: Honduras Coral Reefs
Black Carbon
Miami Canal Surveys
Cape Cod Lakes
African Dust Lecture
Rock Stories
Falmouth, MA Public Schools
WHFC Web Site
Coral Reefs
Sea-Level Rise & Coastal Disasters
Chesapeake Bay
Water Quality
Restoring Louisiana's Coastal Ecosystems
ArcGIS 8.1
Marine Technology
Two New Postdocs
Student & Visiting Scientist
Data Management
WHFC Visitors
Cape Cod Marathon
Dec./Jan. Publications List
|