Pacific Islands Benthic Habitat Mapping Center (PIBHMC), Coral Reef Ecosystem Division (CRED), Pacific Islands Fisheries Science Center (PIFSC), National Marine Fisheries Service (NMFS), National Oceanic and Atmospheric Administration (NOAA)
200611
CRED Optical Validation Data at the island of Ofu and Olosega in American Samoa, 2006 to support Benthic Habitat Mapping (TOAD)
Video imagery, track line navigation files, and log sheets
http://www.soest.hawaii.edu/pibhmc/
http://www.soest.hawaii.edu/pibhmc/pibhmc_amsamoa_ofu_optical.htm
Optical validation data were collected using a Tethered Optical Assessment Device (TOAD), an underwater
sled equipped with an underwater digital video camera and lights. Data were collected in American Samoa, around
the islands of Ofu and Olosega to support Benthic Habitat Mapping efforts during NOAA Ship Hi'ialakai
HI0602, from February 26 to March 1, 2006.
These data provide optical observations that will be correlated with bathymetry and acoustic backscatter
imagery to develop a benthic habitat map of Ofu and Olosega. Refer to supplemental information for description of
instrument and survey.
Ofu and Olosega Islands are part of the Manu'a Island group in American Samoa, situated
approximately 100 km northeast of Tutuila and 20km west of Ta'u. Centered at 14.17 degress S, 169.65 degrees W, the twin islands
have very little human settlement. Ofu and Olosega are steep, volcanic high islands that lie only 75 m apart and
are connected by a bridge and road built across the shallow reef flat. Shallow multibeam mapping was conducted in
2004 and revealed approximately 60 km2 of previously uncharted bank top (less than 300 m) that extends 0.2 to 2 km
from shore and then drops abruptly to oceanic depths. An underwater portion of the National Park of American Samoa,
which has exceptionally prolific coral growth, is located on the south shore of Ofu Island.
Optical validation data were collected using the Tethered Optical Assessment Device (TOAD), a sled equipped with
underwater video camera and lights.
These data are used to provide ground-truth validation for benthic habitat maps based on multibeam echosounder
surveys. Camera sled deployments were conducted at night, usually between 1800 and midnight. The duration of each
tow varied but averaged about 40 minutes of bottom time at a given location. The camera sled was deployed from the
port J-frame mounted amidships on the NOAA Ship Oscar Elton Sette. At each station the ship was positioned with the
wind on the port side and drifted downwind; occasional light turns were applied to the ship's screws if necessary
to reduce the ship's motion. The TOAD was lowered slowly to the bottom by the deck crew using a capstan. The
operator monitored a live video feed from the camera and began recording data on a video tape recorder. When the
camera reached bottom the deck crew was notified by radio to stop lowering. The operator continued to monitor the
vehicle and provided commands to raise or lower it to keep the camera just above the bottom.
Equipment Description: The new TOAD sled body used for the 2004 data collection is constructed from a shortened
Phantom ROV body with a tail piece added for stability. It is equipped with a Deep Sea Power and Light Multi SeaCam 2060
color video camera, two 500 W DeepSea Power and Light Multi-SeaLite model 1050 underwater lights, a sonar altimeter
to detect the height of the camera above the seafloor, a pair of parallel lasers to determine the size/scale of
viewed objects, a compass to determine the sled heading and orientation, and a depth (pressure) sensor. The video
signal from the sled is send via a coaxial conductor within a 200 m long and 127 mm diameter umbilical cable to a
topside control unit.
Name & address of person collecting data:
Scott Ferguson
NOAA IRC
NMFS/PIFSC/CRED
1845 WASP Blvd., Building 176
Honolulu, HI 96818
Data Files: Video data were recorded to digital video cassette using a video recorder mounted in the control console.
Video backups were made at the end of each day. Hypack Max (version 2.12A) hydrographic survey software was used
to record GPS data, water depth, length of umbilical cable in the water, and camera sled information (height,
heading, etc.), which provide ship and camera sled positions for the duration of individual tows.
File naming convention: Each tow is given a name consisting of a three-letter designator for the island area,
followed by a two-digit year and a three-digit tow number, which increments by one for each new tow around that
island. For example, during HI0602 (NOAA Ship Hi'ialakai 2nd cruise in calendar year 2006) the consecutive
tows at Ofu started at OFU06001. For subsequent cruises in the same year, the tow numbers will increment by
100, so the first tow on the next cruise to Ofu in 2006 will be tow number OFU06100. Video tape labels and paper
log forms are also annotated with the tow name; if more than one tape is required for a tow, consecutive letters
are added to the end of the tow number (OFU06100a, OFU06100b, OFU06100c...). Navigation files generated by Hypack
Max follow the Hypack CHS filename format consisting of the year, the first two letters of the platform name, the
Julian date, and the hour and minute in which the file was started, followed by the extension .raw. For example, a
file begun at 1935 on Dec. 10, 2004 (Julian date 345) aboard the Carolinian would be 2004CA3451935.raw.
Time Correlation: All clocks were synchronized to UTC at the beginning of each day's operations. Two clocks were
manually synchronized to GPS-derived times: the acquisition computer clock and the internal clock of the OSD-79
on-screen display unit.
Resource Description: Digital video imagery that is geo-referenced to navigation files.
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ground condition
None planned
-169.705274
-169.583687
-14.133505
-14.203385
NCEI Geoportal FilterCoRIS_MetadataCRCP ProjectBenthic Habitat Mapping and Characterization - American Samoa and PRIA1084
CoRIS Theme Thesaurus
EARTH SCIENCE > Biosphere > Aquatic Habitat > Benthic Habitat
EARTH SCIENCE > Biosphere > Zoology > Corals > Reef monitoring and assessment > Photographic analysis > Videography
EARTH SCIENCE > Biosphere > Zoology > Corals > Reef monitoring and assessment > Mapping
None
Tethered Optical Assessment Device (TOAD)
Underwater video
HI0602
CoRIS Discovery Thesaurus
Visual Images > Habitats
ISO 19115 Topic Category
environment
007
biota
002
CoRIS Place Thesaurus
OCEAN BASIN > Pacific Ocean > Manu'a Group > Ofu Island (14S169W0013)
COUNTRY/TERRITORY > United States of America > American Samoa > American Samoa > Ofu Island (14S169W0013)
OCEAN BASIN > Pacific Ocean > Manu'a Group > Olosega Island (14S169W0014)
COUNTRY/TERRITORY > United States of America > American Samoa > American Samoa > Olosega Island (14S169W0014)
CoRIS Region
AmSam
None
Please acknowledge the NOAA Coral Reef Ecosystem Division, Pacific Islands Fisheries Science Center as
the source of this information.
Pacific Islands Benthic Habitat Mapping Center (PIBHMC), Coral Reef Ecosystem Division (CRED), Pacific Islands Fisheries Science Center (PIFSC), National Marine Fisheries Service (NMFS), National Oceanic and Atmospheric Administration (NOAA)
John Rooney
mailing and physical address
NOAA IRC
NMFS/PIFSC/CRED
1845 WASP Blvd., Building 176
Honolulu
HI
96818
808 725-5360
808 725-5429
nmfs.pic.credinfo@noaa.gov
e-mail preferred
Pacific Island Benthic Habitat Mapping Center, Coral Reef Ecosystem Division (CRED), Pacific Islands
Fisheries Science Center (PIFSC), NOAA
Not applicable
Unclassified
Not applicable
Unspecified
Complete
Hypack Max includes a window for manual entry of the length of camera sled
cable paid out, a utility to enter horizontal and vertical offsets between the GPS antenna and sheave over which
the camera sled cable passes, and a built-in caternary function. Using these data, Hypack Max automatically
estimates the camera sled's position. Analysis of tow data indicate that horizontal positional uncertainty associated
with the location of the camera sled recorded in Hypack is plus or minus 13 m.
After a tow was completed the video tape data was reviewed by spot-checking the tape to
verify that data were recorded. Backups were made at the end of each day.Raw data files recorded time,
horizontal position, and ship's heading information, and were copied from the acquisition computer to the data
archive. Tow-specific metadata were recorded in the data archive in the same location as the raw data, in a
spreadsheet that was then referred to in creating metadata records of each island where data were collected
during the cruise. Raw data files were exported as comma-delimited text files which were then imported into
ArcGIS 9.x and saved as shapefiles. Video still frames spaced 20 m apart were analyzed. For the analysis, five
circles approximately 0.5 mm in diameter and spaced equidistantly were drawn in a horizontal line on a piece of
clear plastic sheet taped to a computer monitor screen. For every still frame, within the center of each circle
the substrate (rock, sand, rubble, etc.) living cover (seagrass, scleractinian [stony] coral, macroalgae, etc)
and growth morphology of coral colonies (branching, encrusting, etc) were identified. Classification information
was recorded on a spreadsheet for each camera tow according to the codes and include the type of substrate,
living cover (if any), and dominant variation in relief seen in the image. The substrate within the first circle
is recorded under the column labeled S1 while the living cover and coral growth morphology within the same
circle are recorded under the columns labeled C1 and CM1. Data from the second circle are recorded under columns
S2, C2, CM2 and so on. Spreadsheets with benthic classification data from video analysis are attributed to the
appropriate tow track shapefile and along-track location. Color coding is then applied to highlight features of
interest, such as the percentage of the seafloor covered by living corals or other benthic fauna found at each
location or different types of substrate.
20061130
Pacific Islands Benthic Habitat Mapping Center (PIBHMC), Coral Reef Ecosystem Division (CRED), Pacific Islands Fisheries Science Center (PIFSC), National Marine Fisheries Service (NMFS), National Oceanic and Atmospheric Administration (NOAA)
John Rooney
mailing and physical address
NOAA IRC
NMFS/PIFSC/CRED
1845 WASP Blvd., Building 176
Honolulu
HI
96818
808 725-5360
808 725-5429
nmfs.pic.credinfo@noaa.gov
e-mail preferred
Downloadable Data
These data are not to be used for navigational purposes. NOAA makes no warranty regarding these
data, expressed or implied, nor does the fact of distribution constitute such a warranty. NOAA cannot assume liability
for any damages caused by any errors or omissions in these data, nor as a result of the failure of these data to
function on a particular system.
ASCII
Each comma-delimited record contains the UTC date and time, latitude, longitude,
altitude, vehicle depth, and water depth.
List of navigation files:
The shapefiles showing camera sled tracks listed below consist of a collection of files with the names listed
below, followed by these extensions: .dbf, .shp, .shx, and .prj. All file types are necessary to properly
displaying the source data.
OFU06001-010 (10 files)
CD-ROM
ISO 9660
avi
http://www.soest.hawaii.edu/pibhmc/pibhmc_amsamoa_optical_data.html
None
Data is available in VHS format. Contact distributor.
These data were recorded on 16 video tapes
List of video tapes:
OFU06001a-c, Mini DV, Master and Backup
OFU06002a-b, Mini DV, Master and Backup
OFU06003a-b, Mini DV, Master and Backup
OFU06004, Mini DV, Master and Backup
OFU06005a-b, Mini DV, Master and Backup
OFU06006, Mini DV, Master and Backup
OFU06007, Mini DV, Master and Backup
OFU06008, Mini DV, Master and Backup
OFU06009, Mini DV, Master and Backup
OFU06010a-b, Mini DV, Master and Backup
None
20200329
20100504
Pacific Islands Benthic Habitat Mapping Center (PIBHMC), Coral Reef Ecosystem Division (CRED), Pacific Islands Fisheries Science Center (PIFSC), National Marine Fisheries Service (NMFS), National Oceanic and Atmospheric Administration (NOAA)
mailing and physical address
NOAA IRC
NMFS/PIFSC/CRED
1845 WASP Blvd., Building 176
Honolulu
HI
96818
808 725-5360
808 725-5429
nmfs.pic.credinfo@noaa.gov
e-mail preferred
FGDC Content Standards for Digital Geospatial Metadata
FGDC-STD-001-1998
20100504023205
None
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https://www.coris.noaa.gov/metadata/records/html/cred_toad_ofu_olosega_hi0602_2006.html
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