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Mapping the Long Island Sound Seafloor

This project began in April 2012 and is Ongoing

Long Island Sound is a region vital to our Nation’s economy, security, culture, and ecology. A new collaborative effort by state, federal and academic partners is helping managers and officials balance competing interests and uses by integrating various seafloor mapping technologies and capabilities. We will present the most comprehensive picture of the Sound, improve understanding of the area’s underwater environment, and provide mapping tools critical to ocean and environmental planning.

Why We Care
The challenge for effective coastal planning is balancing the demands of proposed development activities, such as telecommunication cables, gas pipelines, and other large scale infrastructure, while ensuring the sustainability and health of marine environments. The types of products to be produced for Long Island Sound have a myriad of applications to assist in marine spatial planning. These issues range from site-specific regulatory and permitting assessments of development proposals, to broader long-term monitoring of ecological conditions within the Sound. For instance, these data will help answer specific questions needed for environmental analyses including:

  • Where are ecologically significant areas in the Sound that should remain untouched?
  • Are current ecological sampling strategies appropriate for monitoring biological health?
  • What biological communities are most heavily impacted by human stressors and where are they most at risk?
  • Are current resource management strategies effective in maintaining a healthy Long Island Sound ecosystem?
  • What are areas that could support infrastructure siting and why?

What We Have Done/Are Doing
Extensive ship-based acoustic and habitat surveys have already been completed, with additional sampling to continue in the near future. The first phase of the project is concentrated around Stratford Shoals, which is located in central Long Island Sound, and extends to the Connecticut and New York shorelines. This Pilot Priority area is depicted in the map below. A suite of marine informational products will be produced to assist decision makers in making informed management policies. These products include:

  1. Benthic and Ecological Processes – Benthic habitat maps provide information about the extent and composition of marine resources.  Understanding benthic habitat structure and ecological characteristics are critical to guiding the proper management and conservation of benthic environments.
  2. Acoustic Intensity and Seafloor Topography – To provide meaningful information about the distribution and composition of seafloor habitats, backscatter-derived images (also known as acoustic intensity products) depicting the composition, roughness, and texture of the seafloor are required.  These data, when combined with additional products that provide depth and topographic relief, are the foundation for building tools that address benthic habitats and other environmental conditions.
  3. Sediment Texture & Grain Size Distribution – Mud, sand, and gravel-dominated areas provide very different habitats, so sediment grain size composition and texture are essential components for habitat classification.
  4. Sedimentary Environments – The stability and suitability of different habitats for various species depend on processes such as erosion, deposition, and transportation of sediment. Mapping these sedimentary environments is not only important for understanding habitats; it also helps planners anticipate the potential for change.
  5. Physical & Chemical Environments – The project will create products depicting temperature, salinity, dissolved oxygen and bottom stress.  These are central elements of habitat classification and are critical in predicting and monitoring the impact of management decisions and marine resource conservation.
  6. Data Management – The project team will utilize a central data management system to facilitate the storage and transfer of information during the project.  As data sets are finalized, they will be made available to the public through the data system as well as to appropriate repositories such as the U.S. National Geophysical Data Center (NGDC).

We are working with NOAA’s Office of Coast Survey (OCS) and academic consortiums led by the University of Connecticut (UConn) and Columbia University’s Lamont Doherty Earth Observatory (LDEO). This partnership exemplifies NOAA’s commitment to integrated ocean and coastal mapping--to “map once, use many times.” The philosophy emphasizes coordination with State and Regional partners, reducing redundancies, improving efficiencies, developing common standards, and stimulating innovation and technological development.

Next Steps
Upon completion of the Pilot Project Area, mapping efforts will continue mapping in two other priority areas. The eastern area is located in proximity to New Haven, CT and the western area extending from Huntington Bay, NY to Connecticut. (Areas depicted by a black outline in the map below).

Additional Resources

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