[Coral-List] Yet another coral syndrome outbreak in Puerto Rico

[Hernandez Edwin]

Dear coral-listers.

This short message is a follow-up message to the one
just posted by Ernesto Weil (UPR-M). We have been
expanding our long-term coral reef monitoring program
in the eastern coast of Puerto Rico to several remote
reef sites. The last 2 additions include Los Corchos
Reef and Culebrita Island. These are located east of
Culebra Island, at approximately 30-35 km off eastern
Puerto Rico. These are the easternmost structural
coral reef habitats in Puerto Rico. Los Corchos Reef
supports the largest known living stands of Acropora
cervicornis in the eastern Puerto Rican shelf. Coral
cover still reaches values of 70-80%.

On September 23, 2004 we documented an astonishing
amount of dying Acropora cervicornis colonies by a
band-type of syndrome. A preliminary assessment of
recently fixed transects suggests that approximately
>80% of the colonies were showing active infections.
All of the infected colonies were also part of 3-Spot
damselfish (Stegastes planifrons) territories. This
reef is showing evident signs of overfishing (=
decline in major fish functional groups). There was
also a large amount of recently dead entire colonies.

In addition, there was a large amount of recently
fragmented A. cervicornis colonies (not cuantified) in
depths shallower than 5 m. In Culebrita Island we also
documented on September 24, 2004 a few recently
fragmented colonies of A. palmata. This fragmentation
was caused by the tropical storm Jeanne (Sept. 14-15,
2004) with estimated breaking waves of 4 to 5 m. No
diseases or syndromes were documented on A. palmata
fragments, but most of the A. cervicornis (not
cuantified) were showing signs of rapid and recent
mortality.

Tissue samples were collected from several standing
colonies for molecular microbiology analysis.

Finally, we have also observed the presence of the
yellow-blotch syndrome in the Montastraea annularis
species complex in our fixed transects all around
Culebra Island. We have not quantified that data yet.
But certainly, yellow-blotch, white pox (A. palmata),
and this unknown rapid-moving band-like syndrome (A.
cervicornis) have been around in Culebra for several
months now, but seem to be getting stronger recently.

Just a final thought. During the last 18 months we
have been taking a closer look to A. cervicornis
populations and disease/syndrome effects (=mortality)
have been associated with severe runoff events and to
algal blooms following such events. The actual
widespread event occurred after 21+ inches of rain as
a result of tropical storm Jeanne that has caused a
major runoff event and a impressive phytoplankton
bloom that has reduced vissibility in some offshore
areas from >30 m to about 15 m, and in inshore areas
(<1 km) from about 20 m to 0.5 m. Somehow these events
are inducing significant physiological stress in coral
that are causing major localized mortality events.
This seems to contradict the current thinking that
corals are diseased and killed by regionally-dispersed
factors. Are these syndromes really "diseases" or a
physiological response to changes in the
coral-associated microbe community! Any thoughts are
welcome!

Saludos!

Edwin


Edwin A. Hernandez, PhD
University of Puerto Rico
Department of Biology
Coral Reef Research Group
PO Box 23360
San Juan, PR 00931-3360
Tel. 787-764-0000, x-4880
Fax 787-764-3875
e-mail: coral_giac at yahoo.com


		
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