| Summary: | This data package is formatted as a Darwin Core Archive (DwC-A, event core). For more information on Darwin Core see https://www.tdwg.org/standards/dwc/. This Level 2 data package was derived from the Level 1 data package found here: https://pasta.lternet.edu/package/metadata/eml/edi/357/2, which was derived from the Level 0 data package found here: https://pasta.lternet.edu/package/metadata/eml/edi/291/2. The abstract below was extracted from the Level 0 data package and is included for context: 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. This project focuses on the long-term community dynamics of shallow coral reefs on the south shore of St. John. The project began in 1987 and consists of permanently marked areas that are photographed annually for the analysis of benthic community structure and areas that are censused annually for the density of juvenile corals. All of the work takes place on reefs at less than 14 m depth, and virtually all of the study sites fall between Cabritte Point to the east, and White Point to the west. The project is independent of, but complimentary to, the larger-scale reef monitoring program conducted by the Virgin Islands National Park. The project described here is an independent academic effort led by Dr. Peter Edmunds from California State University, Northridge. The objective of this study is to describe coral reef community dynamics in great detail from a small area to first, elucidate the patterns of change in key components of the benthic coral reefs, and second, to test for processes that drive the changes observed. The core of the project relies on high resolution digital images that have been recorded at least annually since December 1987, and are available here as a invaluable photographic archive for further analysis and to corroborate existing numerical descriptions. In addition to the photographs, the density of juvenile corals has been recorded at multiple sites since 1994.
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