Citation:
Citation_Information:
Originator:
Coral Reef Ecosystem Division (CRED), Pacific Islands Fisheries Science Center (PIFSC), National Marine Fisheries Service (NMFS), National Oceanic and Atmospheric Administration (NOAA)
Publication_Date: 20050822
Title:
CRED Towed-Diver Benthic Characterization Surveys at Saipan Island, Marianas Archipelago in 2003
Geospatial_Data_Presentation_Form: spreadsheet
Online_Linkage:
Description:
Abstract:
To support NOAA Coral Reef Conservation Program (CRCP) long-term goals for sustainable management and conservation of coral reef ecosystems, towed-diver surveys (aka. towboard surveys) were conducted by the Coral Reef Ecosystem Division (CRED) of the NOAA Pacific Islands Fisheries Science Center (PIFSC) as part of biennial Pacific Reef Assessment and Monitoring Program (RAMP) Cruises. 6 towboard surveys (11.8192 km in length), were conducted at Saipan Island during the Marianas Archipelago RAMP Cruise OES0307 from 19 August - 30 September 2003.
Towboard surveys are a good method for obtaining a general description of large reef areas, assessing the status of low-density populations of large-bodied reef fish, large-scale disturbances (e.g., bleaching), general distribution and abundance patterns of macro-invertebrates (e.g., COT, giant clams), and for assessing trends in these populations and metrics.
A pair of scuba divers (1 fish and 1 benthic diver) are towed 60 m behind a small survey launch at a speed of 1-2 knots and a depth of approximately 15m. Each survey is 50 min long, covers about 2 km of habitat, and is divided into ten 5-minute survey segments.
The fish diver records, to the lowest possible taxon, all large-bodied reef fishes (>50cmTL) seen within 5m either side and 10m in front of the towboard. Length of each individual is estimated to the nearest cm. The fish towboard is also outfitted with a forward-facing digital video camera to record the survey swath.
The benthic diver records percent cover of coral and macroalgae, estimates benthic habitat type and complexity, and censuses a suite of benthic macroinvertebrates including Crown of Thorns sea stars and sea urchins. The benthic towboard is equipped with a downward-facing digital still camera which images the benthos at 15 second intervals. These images are analyzed for percent cover of coral, algae, and other benthic components.
Both towboards are equipped with SEABIRD SBE-39 temperature/depth sensors set to record at 5 second intervals. Latitude and longitude of each survey track is recorded at 15 second intervals using a Global Positioning System (GPS) receiver onboard the tow boat. A layback algorithm is applied to more accurately map the position of the divers with respect to the reef environment. This algorithm calculates the position of the divers based on the position of the tow boat taking into account the length of the tow rope, the depth of the divers, and the curvature of the survey track.
This metadata applies to the benthic characterization observations.
Purpose:
Part of a long-term monitoring program at biennial intervals which documents the state of the reefs.
Supplemental_Information:
The benthic characterization observation data includes benthic composition, complexity estimations, observed macro-invertebrates, and observed man-made objects. Classification of habitat complexity was recorded in six categories: low (L), medium-low (ML), medium (M), medium-high (MH), high (H), and very high (VH). Benthic cover was estimated for four different types of substrate: hard substrate/pavement, sand, rubble, and live hard (scleractinian) coral.
The time of the benthic digital photos were set to the GMT time. There were approximately 200 pictures of each 50-minute towed survey track. The resolution at "Draft" quality (the lowest) is 72 pixels/inch. The resolution at "Best" quality (the highest) is 266 pixels/inch. The naming convention of benthic photos is ***MMDDYY_X_###.JPG, where *** is 3 letters abbreviation of island/bank surveyed, MMDDYY is the local date of towboard survey, X is the Xth dive on the day of MMDDYY, and ### is the sequence number of the pictures taken at the Xth dive. For example, JAR032106_3_108.JPG means the picture was the 108th picture taken at 3rd dive on March 21, 2006 at Jarvis Island.
Time_Period_of_Content:
Time_Period_Information:
Range_of_Dates/Times:
Beginning_Date: 20030822
Ending_Date: 20030822
Currentness_Reference: Ground condition
Status:
Progress: Complete
Maintenance_and_Update_Frequency: asNeeded
Spatial_Domain:
Bounding_Coordinates:
West_Bounding_Coordinate: 145.682035
East_Bounding_Coordinate: 145.848199
North_Bounding_Coordinate: 15.298604
South_Bounding_Coordinate: 15.079644
Keywords:
Theme:
Theme_Keyword_Thesaurus: NCEI Geoportal Filter
Theme_Keyword: CoRIS_Metadata
Theme:
Theme_Keyword_Thesaurus: CRCP Project
Theme_Keyword:
Pacific Reef Assessment and Monitoring Program (Pacific RAMP): Biennial monitoring for the U.S. Pacific Islands and Atolls
Theme_Keyword: 1221
Theme:
Theme_Keyword_Thesaurus: None
Theme_Keyword: Marine Ecosystem
Theme_Keyword: Reef Assessment and Monitoring Program (RAMP)
Theme_Keyword: Coral Reef
Theme_Keyword: Towed Diver Surveys
Theme_Keyword: Benthic Habitats
Theme_Keyword: Marianas Archipelago
Theme_Keyword: Saipan Island
Theme_Keyword: OES0307
Theme:
Theme_Keyword_Thesaurus: CoRIS Theme Thesaurus
Theme_Keyword: EARTH SCIENCE > Oceans > Coastal Processes > Coral Reefs
Theme_Keyword:
EARTH SCIENCE > Oceans > Coastal Processes > Coral Reefs > Coral reef ecology
Theme_Keyword:
EARTH SCIENCE > Oceans > Coastal Processes > Coral Reefs > Coral reef ecology > Habitats
Theme_Keyword:
EARTH SCIENCE > Biosphere > Zoology > Corals > Reef monitoring and assessment
Theme_Keyword: EARTH SCIENCE > Biosphere > Aquatic Habitat > Benthic Habitat
Theme:
Theme_Keyword_Thesaurus: CoRIS Discovery Thesaurus
Theme_Keyword: Numeric Data Sets > Biology
Theme:
Theme_Keyword_Thesaurus: ISO 19115 Topic Category
Theme_Keyword: biota
Theme_Keyword: 002
Place:
Place_Keyword_Thesaurus: None
Place_Keyword: The United States
Place_Keyword: Marianas Archipelago
Place_Keyword: Saipan Island
Place:
Place_Keyword_Thesaurus: CoRIS Place Thesaurus
Place_Keyword:
OCEAN BASIN > Pacific Ocean > Western Pacific Ocean > Saipan Island > Saipan Island (15N145E0002)
Place_Keyword:
COUNTRY/TERRITORY > Northern Mariana Islands > Saipan > Saipan Island (15N145E0002)
Place:
Place_Keyword_Thesaurus: CoRIS Region
Place_Keyword: CNMI
Access_Constraints: Data are available two years following data collection date.
Use_Constraints:
Please cite CRED when using the data. Coral Reef Ecosystem Division, Pacific Islands Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration
Point_of_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization:
Coral Reef Ecosystem Division (CRED), Pacific Islands Fisheries Science Center (PIFSC), National Marine Fisheries Service (NMFS), National Oceanic and Atmospheric Administration (NOAA)
Contact_Address:
Address_Type: mailing and physical address
Address: NOAA IRC
Address: NMFS/PIFSC/CRED
Address: 1845 WASP Blvd., Building 176
City: Honolulu
State_or_Province: HI
Postal_Code: 96818
Country: USA
Contact_Voice_Telephone: 808 725-5360
Contact_Facsimile_Telephone: 808 725-5429
Contact_Electronic_Mail_Address: nmfs.pic.credinfo@noaa.gov
Contact_Instructions: e-mail preferred
Data_Set_Credit:
Rusty Brainard and Molly Timmers, Coral Reef Ecosystem Division (CRED), Pacific Islands Fisheries Sciences Center, National Marine Fisheries Service, NOAA
Security_Information:
Security_Classification_System: Not applicable
Security_Classification: Unclassified
Security_Handling_Description: Not applicable
Native_Data_Set_Environment: Oracle