Project Summary for 2005–04–11: ROV MPA groudtruthing cruise
Background:
This project will produce high–resolution, geo–referenced multibeam and backscatter maps of several proposed MPAs off the southeast coast of the U.S. The South Atlantic Fishery Management Council (SAFMC) anticipates the implementation of nine Marine Protected Areas between Cape Hatteras, NC and the Florida Keys in the fall of 2006. Five of these sites contain natural reef habitat, are located between southern NC and northern FL, and were examined by NOAA Fisheries during the spring of 2004. The initial ROV and stationary video surveys revealed extensive reef structure and associated fish assemblages with dive site selection based upon local knowledge of anglers and other researchers in addition to split–beam echosounder bathymetry acquired on the spring 2004 cruise. During the cruise, the need for accurate, high resolution bathymetric maps became obvious. The requirement for fine scale maps to stratify the MPAs and select sampling locations cannot be overemphasized.
These MPAs offer the rare opportunity to quantify habitat and fish assemblages before closure for direct comparison after closure. However, mapping is a prerequisite for any comprehensive research program. High resolution multibeam bathymetric and backscatter maps will be produced with this project and will be added to an existing Geographic Information System (GIS) on east coast shelf habitat. The GIS application will be available both on-line and as a CD-ROM product and this effort will be closely coordinated with CoRIS. A hydrographic company will be contracted to collect, process, and compile the data. A university vessel will be the platform used for data acquisition. Video tapes made during the spring 2004 cruise will be used for groundtruthing backscatter data. Completion of this project will greatly advance our ability to evaluate the use of area closures to protect habitat and fish assemblages in the South Atlantic Bight. Multibeam bathymetric and backscatter maps will allow quantification of habitat and stratification of the proposed MPAs by habitat type permitting a stratified random design of site selection for future monitoring.
2005 work plan:
A private hydrographic company, Seafloor Systems, Inc., will be contracted to collect, process, and compile multibeam bathymetric and backscatter data within and adjacent to five proposed MPAs in the U.S. South Atlantic. A university vessel, owned by UNC–Wilmington, will be contracted to provide ship support. A multibeam system operating at 300 KHz, will provide the highest resolution product down to water depths of 150 m. Standard hydrographic protocols will be followed to ensure complete coverage and a high quality product. Cost effectiveness is obtained by combining two mapping projects into one cruise, thereby reducing mobilization, de–mobilization, and travel costs. Seafloor Systems has provided mapping services for NOAA in the Oculina HAPC with fully satisfactory results.
Forty five sea days were originally requested for this proposal. After accounting for the reduction in support, transit time, and port days, 13 days of surveying are anticipated. This should allow for approximately 1500 linear miles of mapping. Intertrack spacing will vary by depth and precludes an exact estimation of total area to be covered, however this should provide sufficient time for mapping important target areas in five of the proposed MPAs and significant adjacent, open–to–fishing areas for future comparisons. The deliverables for this project will be the bathymetric and backscatter maps. Success will be easily measured by the area mapped at the required resolution. Once again, previous experience with both the vessel and hydrographic company suggests a high probability of success.
It should be noted the SAFMC has proposed nine sites for area closure to protect seven reef fish species (snowy, warsaw, misty, and yellowedge grouper, speckled hind, tilefish and blueline tilefish). This project proposes to map five of the nine proposed MPAs. Two are remote from the other seven and excluded from the incumbent project due to logistic concerns. Artificial reefs are planned for the final two sites. These sites have been excluded here as our focus is on the changes induced in natural habitats by fishing restrictions. These proposed sites will be established to ameliorate heavy fishing pressure on deep reef species, and mapping of the areas is a crucial step in designing a robust evaluation of this management tool. Increased awareness of the habitat in these areas will provide a wide variety of researchers the information needed to execute far more robust research projects and answer many questions which would not be possible to do without the precise information available in high resolution multi–beam bathymetric and backscatter maps.
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