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)
200904
CRED Fish Biomass Estimates at Pearl and Hermes Atoll in the Northwestern Hawaiian Islands - 2004
Video imagery, track line navigation files, and log sheets
http://www.soest.hawaii.edu/pibhmc/
http://www.soest.hawaii.edu/pibhmc/pibhmc_nwhi_phr.htm
Fish biomass data were collected using a Towed Optical Assessment Device (TOAD), an underwater sled
equipped with an underwater digital video camera and lights. Data were collected at the Northwestern Hawaiian Islands,
Pearl and Hermes Atoll to support Benthic Habitat Mapping efforts.
These data will provide optical observations that will be correlated with bathymetry and acoustic backscatter imagery
to create a fish biomass map of Pearl and Hermes Atoll. Refer to supplemental information for description of
instrument and survey.
Pearl and Hermes Atoll, located at 27.8N, 175.8W, is an extensive atoll area containing numerous
small islets. The coral reef environment includes 1,166 sq. km of banks shallower than 100 m in depth.
Mobile fauna 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 fish count and biomass maps where benthic habitat
classification has been completed. Camera sled deployments were conducted at night, usually between 1800 and
midnight. Each tow was usually limited to approximately 20 minutes of bottom time at a given location in order to allow for more
tows to be conducted in a given work area and thus increase the spatial distribution of the observations. The camera
sled was deployed from lower arm of the starboard J-frame on the NOAA Ship Hi'ialakai. At each station the ship was
positioned with the wind on the starboard 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. The
operator monitored a live video feed from the camera and began recording data on two video tape recorders. 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 TOAD was deployed from the lower arm of the vessel's J-frame. The TOAD is a camera sled
based on the Guildline MiniBat model 8820 tow body. The frame has been extensively modified from its original configuration
and was configured with a single ROS model 54-00100-13 color underwater video camera and two 500 W DeepSea Power & Light
model 710-0400601 underwater lights mounted on the original sled frame. The MiniBat pressure sensor and wing controller
was also mounted on the frame but no wings were installed. Cable between the sled and the surface consisted of an
underwater electrical cable (cable 1, blue in color) with a separate load-bearing line to support the sled frame. The
electrical cable was clipped to the line at regular intervals upon deployment and removed upon recovery. The load-bearing
line was led to the starboard capstan on the aft deck. All TOAD surface components were located in the Dry Lab in an
equipment rack on the after bulkhead. After operations began we learned that the sled's pressure sensor was not working.
Name & address of person collecting data:
John Rooney
NOAA PIFSC
1125B Ala Moana Blvd
Honolulu, HI 98614
Data Files: Video data were recorded on two video tape recorders. The position of the camera sled was recorded using
Guildline MiniBat In-Tow data acquisition software.
File naming convention: Each tow is given a name consisting of a 3-letter designator for the island area followed by
a two-digit year and three-digit tow number. For example, during HI0401 the first tow was called PHR04001. Video
tape labels, the navigation files (*.glo) and paper log forms are all annotated with the tow name. If the navigation
file is edited during processing the file name has a suffix "a" added. For example, one of the navigation data files
is named "PHR04001a.glo". Metadata were extracted from the navigation data and recorded to a file with the same name
as the navigation file except that a file type of ".met" was appended; for example, "PHR04001a.glo.met"
Time Correlation: All times are based on UTC. Two clocks were set manually synchronized prior to starting data
collection; the clock in the video character generator that was used to annotate the video tape and the TOAD data
acquisition computer clock was used to annotate the navigation (*.glo) files. These clocks were set to UTC at the
beginning of each evening's operations and then compared to one another prior to (and during) each tow. There were
problems maintaining synchronization of the TOAD computer clock during this cruise. See the problems section for a description. (Problems with data could be described here.)
Resource Description: Digital video images that are geo-referenced to navigation files.
20040927
20041001
ground condition
As needed
-176.01938
-175.70098
27.9869
27.7396
CoRIS Theme Thesaurus
EARTH SCIENCE > Biosphere > Aquatic Habitat > Benthic Habitat
EARTH SCIENCE > Biosphere > Zoology > Corals > Reef monitoring and assessment > Mapping
EARTH SCIENCE > Biosphere > Zoology > Corals > Reef monitoring and assessment > Photographic analysis > Videography
EARTH SCIENCE > Oceans > Marine Biology > Fish
None
Towed Optical Assessment Devide (TOAD)
Underwater video
HI0401
CoRIS Discovery Thesaurus
Geographic Information > Fish Stock Characteristics
ISO 19115 Topic Category
environment
007
biota
002
CoRIS Place Thesaurus
OCEAN BASIN > Pacific Ocean > Central Pacific Ocean > Northwestern Hawaiian Islands > Pearl and Hermes Reef (27N176W0001)
COUNTRY/TERRITORY > United States of America > Hawaii > Honolulu > Pearl and Hermes Reef (27N176W0001)
None
Northwestern Hawaiian Islands
CoRIS Region
NWHI
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
1125B Ala Moana Blvd.
Honolulu
HI
96814
(808) 983-3776
(808) 983-2902
pibhmc@soest.hawaii.edu
e-mail preferred
http://data.nodc.noaa.gov/coris/data/NOAA/nmfs/pifsc/cred/TOADbrowse/TOAD_PHA_92dpi.jpg
Pearl and Hermes Atoll, NWHI: TOAD Tows and Multibeam Bathymetry
JPEG
Benthic Habitat Mapping Group, Coral Reef Ecosystem Division (CRED), Pacific Islands Fisheries Science
Center (PIFSC), NOAA
Not applicable
Unclassified
Not applicable
Unspecified
Complete
The horizontal position accuracy for the camera sled position is 100 meters.
There are three primary sources of this error. The ship's positioning is based on GPS SPS, often called standalone
or non-differential GPS positioning. SPS has a measured accuracy of under 5 meters. The position of the GPS antenna
is used; no attempt is made to translocate this position to that of the tow block from which the camera is deployed.
The difference between the tow block and the antenna is about 14 meters. The camera sled position is based a layback
calculation that use ship's course, the amount of cable out and the camera sled depth to develop an estimate of the
camera sled position. The amount of cable deployed is manually entered by the operator during a given camera tow.
After a tow was completed the video tape data was reviewed by spot-checking the master and backup
tape to verify that data were recorded. Navigation data were copied from the acquisition computer to the data
archive. A metadata extractor (gloFilter.py, version 3/06) was run to summarize the navigation data and test for
errors. If errors were detected they were corrected or flagged as appropriate and a new data file was made. This
file's header was updated to document what type of processing occurred. A metadata file was recorded in the data
archive in the same location as the navigation data. Processed navigation data were then read into ArcView 3.2
shapefiles using an ArcView Avenue script named "TOAD.Import.Playback", version 9/25/01, written by Ronald Hoeke.
TOAD video were classified for benthic habitat type to create Optical Validation maps to interpret acoustically
derived data layers. These classified points were imported into a Microsoft Access 2003 database. All fish present
during 15 second intervals before and after these positions were recorded and identified. Using LW coefficients
derived from fishbase.org and size estimates from video, total biomass was calculated for a given point. An area
of 0.0012 hectares per point observation was assumed based on average distances traveled between points as well as
average width of field of view. A table with position, island, biomass(tonnes/hectare), and number of fish was
exported from MS Access into ArcGis v9.2. This file was exported as a shapefile. A column with biomass data was
symbolized using layer file MF_Biomass.lyr to create Fish Biomass Estimates map.
20041015
0.0001
0.0001
Decimal Degrees
D_WGS_1984
WGS_1984
6378137.000000
298.257224
No correction
0.1
meters
Attribute Values
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
1125B Ala Moana Blvd.
Honolulu
HI
96814
(808) 983-3776
(808) 983-2902
pibhmc@soest.hawaii.edu
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 year, day of year, time, latitude, longitude,
velocity north and east, water column depth, vehicle depth, layback, and wing angle. For this data set the fields
for vehicle depth and wing angle do not contain useful data.
List of navigation files:
PHR04001.glo
PHR04002.glo
PHR04003a.glo
PHR04004.glo
PHR04005.glo
PHR04006.glo
PHR04007a.glo
PHR04008.glo
PHR04009.glo
PHR04010.glo
PHR04011.glo
PHR04012.glo
PHR04016a.glo
PHR04017.glo
PHR04018a.glo
PHR04019a.glo
PHR04020.glo
PHR04021.glo
PHR04022.glo
PHR04023.glo
PHR04024a.glo
PHR04025.glo
PHR04026.glo
PHR04027.glo
PHR04028.glo
PHR04029a.glo
CD-ROM
ISO 9660
mini digital video and VHS
List of Video tapes:
PHR04001-002, Mini, DV Master
PHR04003-004, Mini DV, Master
PHR04005, Mini DV, Master
PHR04006-007, Mini DV, Master
PHR04008-009, Mini DV, Master
PHR04010-011, Mini DV, Master
PHR04012-013, Mini DV, Master
PHR04016, Mini DV, Master
PHR04017, Mini DV, Master
PHR04018-019, Mini DV, Master
PHR04020-021, Mini DV, Master
PHR04022, Mini DV, Master
PHR04023, Mini DV, Master
PHR04024-025, Mini DV, Master
PHR04026-027, Mini DV, Master
PHR04028-029, Mini DV, Master
PHR04001-004, VHS, Backup
PHR04005, Mini DV, Backup
PHR04006-007, Mini DV, Backup
PHR04008-009, Mini DV, Backup
PHR04010-011, Mini DV, Backup
PHR04012-013, Mini DV, Backup
PHR04016, Mini DV, Backup
PHR04017, Mini DV, Backup
PHR04018-019, Mini DV, Backup
PHR04020-021, Mini DV, Backup
PHR04022, Mini DV, Backup
PHR04023, Mini DV, Backup
PHR04024-025, Mini DV, Backup
PHR04026-027, Mini DV, Backup
PHR04028-029, Mini DV, Backup
Video cassette tape
Mini DV
None
20121220
20081222
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)
CRED Data Management Team
mailing and physical address
1125B Ala Moana Blvd.
Honolulu
HI
96814
(808) 983-3776
(808) 983-2902
pibhmc@soest.hawaii.edu
e-mail preferred
FGDC Content Standards for Digital Geospatial Metadata
FGDC-STD-001-1998
Local Time
None
None
20081222035141
None
20040927
20041001
http://www.coris.noaa.gov/metadata/records/html/cred_toad_pearl_hermes_hi0401_2004_mobilefauna.html
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