Imaging Surveys of Northern Gulf of Maine and Jordan Basin Habitat Areas for Deep-sea Corals and Sponges
For this project NURTEC provided designed and developed a new towed video system to support seafloor imaging surveys in the northern Gulf of Maine. The project is based on a collaborative pre-proposal (Auster, Packer, Nizinski, Bachmann and Stevenson) to the NOAA Deep Sea Coral Program and draft text by this same group for a deep sea coral amendment to the New England Fishery Management Council. The project addresses NOAA’s long-term mission Goal #3 focused on “Healthy Oceans.” In particular, research and information products that result from this deep sea coral survey effort will directly inform NOAA Fisheries and the New England Fisheries Management Council and improve conservation and sustainable use of “marine fisheries, habitats, and biodiversity …”.
Underwater Technology Development
A significant engineering effort was implemented to accomplish project goals for collecting high resolution seafloor imagery at a large number of stations in the steep topographic settings where corals occur in the northern Gulf of Maine. The Instrumented Seafloor Imaging System (ISIS2) was developed to operate via an electro-optic cable to support high definition and standard definition video cameras, movable lights on pan-tilt units, a digital still camera with electronic flash and a sector scanning sonar. The operational objective was to produce a real time “flyable” vehicle that would provide the pilot with real-time imagery with which to control the depth off bottom via a winch (y-axis movement) and to combine this with the dynamic positioning of the surface support vessel (x-axis movement along the seafloor) to conduct near bottom transects in the precipitous topography of the northern Gulf.
A 14 day cruise off the RV Connecticut with the ISIS2 camera sled was conducted from 11-24 July 2013 and completed 40 camera tows in four areas (western Jordan Basin, Mount Desert Rock-Outer Schoodic Ridges, Blue Hill Bay, and off Monhegan Island). Deep sea corals were present at 15 stations, sea pens at 20 stations and sponge fauna at 29 stations.
Results to Date
Geo-referenced data on camera tow locations and nominal presence-absence of target fauna have been submitted to the NOAA Deep Sea Coral Database. A post-cruise review of selected still imagery produced a set of initial identifications of coral taxa for use in analysis of video imagery. A protocol for throughput of video imagery, selecting and labeling frame-grabs, data types (e.g., taxonomic resolution, habitat classification), data handling (data set structure and storage), and linking to navigation data has been developed at NMFS Sandy Hook. Detailed extraction of data from video imagery is ongoing. A subset of transects has been selected for initial analyses in order to identify limitations based on image and taxonomic resolution. An initial report focused on the occurrence of coral gardens in the Gulf of Maine, a direct result of this work, has been published in the peer-reviewed journal Biodiversity. This project also led to a collaboration with the Ecosystem Monitoring group of NEFSC that focused on producing multibeam maps of seafloor bathymetry at two of our primary survey areas from the NOAA Ship Okeanos Explorer, September 2013 ECOMON cruise. These maps will provide invaluable information to guide future investigations of these topographically challenging deep sea coral habitats. An quick-turnaround publication was generated by the research team:
Peter J. Auster, Morgan Kilgour, David Packer, Rhian Waller, Steven Auscavitch & Les Watling (2013) Octocoral gardens in the Gulf of Maine (NW Atlantic), Biodiversity, 14:4, 193-194, DOI: 10.1080/14888386.2013.850446