Dataset: octocoral
Deployment: WS17317

Transect surveys of octocoral species abundance

View Data: For data, See Dataset Metadata Page: https://www.bco-dmo.org/dataset/751176

Principal Investigator:

Howard Lasker (State University of New York at Buffalo, SUNY Buffalo)

BCO-DMO Data Manager:

Mathew Biddle (Woods Hole Oceanographic Institution, WHOI BCO-DMO)

Project:

RAPID: Resilience of Caribbean octocorals following Hurricanes Irma and Maria (Octocorals and Hurricanes)

Current State:

Preliminary and in progress

Version:

Version Date:

2018-12-18

Expand/Collapse All

Description

This dataset contains octocoral colony heights measured during transect surveys at four sites on the south shore of St. John, US Virgin Islands in November 2017 following Hurricanes Irma and Maria.

Methods & Sampling

Dataset acquisition description

Survey design:
All sites were located at 6 to 9 meters depth.

Censuses at East Cabritte, Europa and Tektite were based on 50x10m areas that were arbitrarily selected and permanently marked with stainless steel eyebolts at the corners of the sites. A total of six transect lines, also marked with eyebolts, were laid out at 10 m intervals. All octocorals present in 1 x 1 m quadrats along the 10-meter long transects were scored. In 2014 ten quadrats were surveyed along each line. In 2015 and 2016 ten quadrats were scored along each transect line at Europa and Tektite and five randomly chosen quadrats were surveyed at East Cabritte. The transect identifier "transect_pos" has values 0, 10, 20, 30, 40 or 50 which represent position in meters within the 50x10 survey area corresponding to each of the 6 transects (e.g. 20 = 20m).

The census at Booby Rock was conducted in a single day in which 2 transects were randomly placed along a 50 m line that was arbitrarily placed on a constant depth contour. Only 4 1x1 m quadrats were surveyed along each transect. The transect identifier (transect_pos) for transects at Booby Rock refers to position along the 50 m line.

Sampling methods:
Identifications were based on traits visible in the field, and samples of representative colonies were collected for further analysis in cases in which field identification was uncertain. Sclerites from those samples were examined for species identification.

Colony heights were measured as the maximum distance from the base of the octocoral colony until the farthest tips of the branch (i.e. not necessarily perpendicular to the substrate). All measures rounded to the nearest cm with the exception of 5 cm which only includes colonies >= 5 cm. Starting in 2016, measures less than 5 cm reflect colonies with thick branches which could only have <5 cm heights due to partial mortality.

Two height measures are present, height of living tissue, which only includes that part of the axis with living tissue and total height which is the distance from the base to the tip of the tallest branch regardless of whether the tips or base had living tissue. (Only colonies with some living tissue were measured).

Species names for field_codes in this dataset can be found in the related dataset: https://www.bco-dmo.org/dataset/733063

These data are a continuation of BCO-DMO project "Ecology and functional biology of octocoral communities" (http://www.bco-dmo.org/project/562086)

Data Processing Description

Dataset Processing Description

BCO-DMO Processing Notes:

added conventional header with dataset name, PI name, version date
modified parameter names to conform with BCO-DMO naming conventions
added lat, lon, Genus_Species, Genus, and Species fields
converted latitude and longitude to decimal degrees
re-formatted date from d-Mon-yy to yyyymmdd

More information about this dataset deployment

Funding

Award Number	Funding Source
OCE-1801475	NSF Division of Ocean Sciences

Instruments

None available yet

Parameters

Supplied Name	Supplied description	Supplied Units	Standard Name
Census_Year	Census Year	unitless	year
Date	Day - Month - Year on which data were collected.	unitless	date
Site	Census locations	unitless	site
Transect_Position	Transects positioned in a marked 50x10m area with stainless steel eye bolts marking each corner and each of the 6 transect. Transects were 10m long across the 50x10m area. So there were 0m; 10m; 20m; 30m; 40m; 50m.	meters (m)	transect
Side_of_transect	Side of the transect tape (Left or Right) orientation looking towards open ocean with the nearest shore to the back.	unitless	site_descrip
Meter_on_transect	From 0m to 9m. 1x1m quadrats were positioned randomly along the 10 m transect. The values refer to the position of the "shoreward" corner of the quadrat. Thus "0"refers to the quadrat placed between the 0 and 1 meter marks	meters (m)	transect
Species_code	Octocorals species acronyms. Field identifications of Pseudoplexaura flagellosa and P. wagenaari are difficult among small colonies and for analysis purposes the two species should be lumped as a single group. Field identifications of Eunicea mammosa E. laxispica and E. succinea are sometimes difficult s and for analysis purposes the two species should be lumped as a single group. LINES WITH NO SPECIES ENTRY IDENTIFY QUADRATS IN WHICH NO OCTOCORALS WERE PRESENT- This is also noted in the comments as "No colonies present"	unitless	species
Height_of_living_tissue	Maximum distance from the base of the octocoral colony until the farthest tips of the longest branch with living tissue (i.e. not necessarily perpendicular to the substrate). All measures rounded to the nearest cm with the exception of 5 cm which only includes colonies >= 5 cm. Measures less than 5 cm reflect colonies with thick branches which could only have <5 cm heights due to partial mortality.	centimeters (cm)	height
Total_Height	total height	centimeters (cm)	height
Genus_Species	Full species name	unitless	species
Genus	Genus name	unitless	genus
Species	Species name	unitless	species
lat	latitude in degrees north	decimal degrees	lat
lon	longitude in degrees east	decimal degrees	lon
Comments_1	Comments. C. gibbosum denotes the presence of Cyphoma giibbosum a grazing snail that strips living tissue from octocoral colonies.	unitless	no_bcodmo_term
Comments_2	Numbers refer to sample numbers of 4 cm dried tissue specimens collected for species identification.	unitless	no_bcodmo_term

Database

Contribute Data

Dataset: octocoral
Deployment: WS17317

Dataset acquisition description

Dataset Processing Description

Database

Contribute Data

Dataset: octocoralDeployment: WS17317

Dataset acquisition description

Dataset Processing Description

Dataset: octocoral
Deployment: WS17317