ERDDAP > info > bcodmo_dataset_1010997_v1

Grid DAP Data	Sub- set	Table DAP Data	Make A Graph	W M S	Source Data Files	Acces- sible	Title	Sum- mary	FGDC, ISO, Metadata	Back- ground Info	RSS	E mail	Institution	Dataset ID
		data	graph		files	public	[Rare corals in the Caribbean: Small coral density from quadrats] - Density of small corals from quadrats on shallow reefs of St. John, USVI, 1994-2024 (RUI: Pattern and process in five decades of change on Caribbean reefs)		M	background			BCO-DMO	bcodmo_dataset_1010997_v1

The Dataset's Variables and Attributes

Row Type	Variable Name	Attribute Name	Data Type	Value
attribute	NC_GLOBAL	cdm_data_type	String	Other
attribute	NC_GLOBAL	Conventions	String	COARDS, CF-1.6, ACDD-1.3
attribute	NC_GLOBAL	creator_email	String	info at bco-dmo.org
attribute	NC_GLOBAL	creator_name	String	BCO-DMO
attribute	NC_GLOBAL	creator_url	String	https://www.bco-dmo.org/
attribute	NC_GLOBAL	doi	String	10.26008/1912/bco-dmo.1010997.1
attribute	NC_GLOBAL	infoUrl	String	https://osprey.bco-dmo.org/dataset/1010997
attribute	NC_GLOBAL	institution	String	BCO-DMO
attribute	NC_GLOBAL	license	String	The data may be used and redistributed for free but is not intended for legal use, since it may contain inaccuracies. Neither the data Contributor, ERD, NOAA, nor the United States Government, nor any of their employees or contractors, makes any warranty, express or implied, including warranties of merchantability and fitness for a particular purpose, or assumes any legal liability for the accuracy, completeness, or usefulness, of this information.
attribute	NC_GLOBAL	sourceUrl	String	(local files)
attribute	NC_GLOBAL	summary	String	Density of small (≤4 cm) brain coral (Diploria and Pseudodiploria) and Porites colonies from quadrats on shallow reefs of St. John, US Virgin Islands, 1994-2024. This dataset supports the results of the publication "Encroaching rarity of Caribbean reef corals" (Edmunds et al., 2026) and is part of the study described below. Study description: Declining coral cover is causing coral colonies to occur farther apart and at lower densities, thus challenging their persistence. Here we test for population declines of Caribbean brain (Diploria labyrinthiformis, Pseudodiploria strigosa, and P. clivosa) and pillar (Dendrogyra cylindrus) corals on the reefs of St. John, US Virgin Islands, and use hectare-scale sampling with geolocation of corals to evaluate the implications of low densities. Sampling over four decades using photoquadrats demonstrated declines in population size, but surveys of 4.63 hectares of reef in 2024 revealed lower density estimates, even though 1,323 colonies were found. Many colonies occurred closer together than chance alone would predict, with mean nearest neighbor distances of 0.8–11.4 m for brain corals and ~74 m for pillar coral. Brain corals also formed clusters in high-density hot spots. Nonetheless, ≤7% of brain corals were close enough together to support 30% fertilization, and 33% of brain colonies were far enough apart that fertilization was 0%. Populations of these species in St. John may be facing further population declines through Allee effects, with the risk acute for Dendrogyra. These results underscore the need to augment monitoring of coral reefs with spatially explicit sampling of corals on a hectare scale. See the Related Datasets section for other datasets from this study.
attribute	NC_GLOBAL	title	String	[Rare corals in the Caribbean: Small coral density from quadrats] - Density of small corals from quadrats on shallow reefs of St. John, USVI, 1994-2024 (RUI: Pattern and process in five decades of change on Caribbean reefs)
variable	Site		String
attribute	Site	long_name	String	Site
attribute	Site	units	String	unitless
variable	Year		int
attribute	Year	actual_range	int	1994, 2024
attribute	Year	long_name	String	Year
attribute	Year	units	String	Year
variable	Quadrat		int
attribute	Quadrat	actual_range	int	1, 40
attribute	Quadrat	long_name	String	Quadrat
attribute	Quadrat	units	String	Number
variable	Diploria		int
attribute	Diploria	actual_range	int	0, 4
attribute	Diploria	long_name	String	Diploria
attribute	Diploria	units	String	Number
variable	Porites		int
attribute	Porites	actual_range	int	0, 17
attribute	Porites	long_name	String	Porites
attribute	Porites	units	String	Number

The information in the table above is also available in other file formats (.csv, .htmlTable, .itx, .json, .jsonlCSV1, .jsonlCSV, .jsonlKVP, .mat, .nc, .nccsv, .tsv, .xhtml) via a RESTful web service.