CRED Towed-Diver Benthic Characterization Surveys at Baker Island, Pacific Remote Island Areas in 2004

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. 8 towboard surveys (16.0781 km in length), were conducted at Baker Island during the Pacific Remote Island Areas RAMP Cruise OES0401 from 8 - 29 January 2004. 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.

                                            {
  "fn": "Coral Reef Ecosystem Division (CRED), Pacific Islands Fisheries Science Center (PIFSC), National Marine Fisheries Service (NMFS), National Oceanic and Atmospheric Administration (NOAA)",
  "@type": "vcard:Contact",
  "hasEmail": "mailto:nmfs.pic.credinfo@noaa.gov"
}
                                        

                                            []
                                        

                                            [
  "CoRIS_Metadata",
  "Long-term Monitoring Of Benthos (Coral, other invertebrates, Algae) - Rapid Ecological Assessments at all U.S. Pacific Islands",
  "1221",
  "Marine Ecosystem",
  "Reef Assessment and Monitoring Program (RAMP)",
  "Coral Reef",
  "Towed Diver Surveys",
  "Benthic Habitats",
  "Pacific Remote Island Areas",
  "Baker Island",
  "OES0401",
  "EARTH SCIENCE > Oceans > Coastal Processes > Coral Reefs",
  "EARTH SCIENCE > Oceans > Coastal Processes > Coral Reefs > Coral reef ecology",
  "EARTH SCIENCE > Oceans > Coastal Processes > Coral Reefs > Coral reef ecology > Habitats",
  "EARTH SCIENCE > Biosphere > Zoology > Corals > Reef monitoring and assessment",
  "EARTH SCIENCE > Biosphere > Aquatic Habitat > Benthic Habitat",
  "Numeric Data Sets > Biology",
  "The United States",
  "Pacific Remote Island Areas",
  "Baker Island",
  "OCEAN BASIN > Pacific Ocean > Central Pacific Ocean > Baker Island > Baker Island (00N176W0001)",
  "COUNTRY/TERRITORY > United States of America > USA Minor Outlying Islands > Baker Island (00N176W0001)",
  "PRIA"
]
                                        

                                            []
                                        

                                            {
  "name": "Coral Reef Ecosystem Division (CRED), Pacific Islands Fisheries Science Center (PIFSC), National Marine Fisheries Service (NMFS), National Oceanic and Atmospheric Administration (NOAA)",
  "@type": "org:Organization"
}