Virgin Islands National Park: Coral Reef: Population Dynamics: Scleractinian corals

These data are evidence of the the long-term dynamics of shallow coral reefs along
the south coast of St. John from as early as 1987. These data describe coral reef
community structure as percent cover based on the analysis of color photographs. All
of these data originate from color images of photoquadrats recorded annually
(usually in the summer) from as early as 1987. The data falls into three groups. The
two groups that are contained in this data package are (1) Tektite & Yawzi and
(2) Random sites. The juvenile coral density is packaged separately. Tektite – this is at 14 m depth on the eastern side of Great Lameshur Bay and is
the original site of the Tektite man-in-the sea project in 1969; this project marked
the birth of the Virgin Islands Ecological Research Station (later the Virgin
Islands Environmental Resource Station) that hosts the field component of the
project. The reef in this location consists of a single buttress that has remained
dominated by Montastraea anularis since the start of the research (1987). These
surveys consist of 30 photoquadrats (1 x 1 m) distributed along three, 10 m
transects. Yawzi – this is at 9 m depth and is on the western side of Great Lameshur Bay and
has been recorded photographically since 1987. This reef also started the study
period dominated by Montastraea annularis, but has degraded much more rapidly that
the Tektite site. These surveys consist of 30 photoquadrats (1 x 1 m) distributed
along three, 10 m transects. Random sites – were added in 1992 to address the concern that the original sites
(Yawzi and Tektite) were selected on “good” areas of reef and, therefore, could only
decline in condition. The Random sites were selected using random coordinates in
1992, and consist of 6 sites (at 7-9 m depth) scattered between Cabritte Point and
White Point. All lie a little shoreward of Yawzi and Tektite, and have always been
characterized by low coral cover (< 10% cover). The surveys consist of 18-40
photoquadrats (0.5 x 0.5 m; with sample size determined by the exposures on a 35 mm
cassette versus digital techniques) that are placed at random points along a
transect.