Plague update from St. John, USVI
jeffmiller at islands.vi
Fri May 24 16:41:30 EDT 2002
We were very interested to read Dr. Edwin Hernandezs report of the increase
in frequency of white plague around Culebra, Puerto Rico, recently posted to
the coral list. This is just a quick note to describe what we've been
seeing with our monthly monitoring of plague on a reef here in St. John, US
Virgin Islands that differs somewhat from the observations in Culebra.
Plague has been present every month since we began monitoring Tektite Reef
in December 1997, and this months monitoring showed less disease than
previous months. (The study site, Tektite Reef, has >50% percent cover by
scleractinian corals with 90% of hard corals being composed of Montastraea
annularis.) Plague occurs most commonly on Montastraea annularis, but
during our May 2002 monitoring we saw it on Agaricia agaricites, Porites
porites, Colpophyllia natans. Over the course of our entire study it has
affected 15 different species.
The May 24, 2002 sampling was our 48th month, and the number of "spots" or
areas of plague on colonies was below average, ranking #21 among all months
sampled. For this year, February had fewer disease occurrences and March
and April had more than this month.
With respect to the total area of all spots covered by disease (we measure
the longest length, and perpendicular axis), again, May was below average
(ranking 19th among all months sampled) and for 2002, there was more area
covered by plague in February and March.
Over the study period, weve seen no correlation of disease with water
temperature or time of year. And although we cant predict disease trends,
this monthly monitoring shows plague is a chronic problem, and continues to
kill coral throughout the year.
Those interested in more information can contact me directly at
William_J_Miller at nps.gov or jeffmiller at islands.vi.
All the best,
Jeff Miller, Fisheries Biologist
National Park Service
Virgin Islands National Park
1300 Cruz Bay Creek
St. John, VI 00830
PH: 340-693-8950 ext: 227
More information about the Coral-list-old