Today we journeyed about 20 miles offshore of the coast of Georgia to retrieve our three bottom-mounted hydrophones. I was really nervous about this trip and everything that could go wrong. We built these moorings ourselves out of concrete, rebar and used car tires and PVC pipe, and zip-tied and electrical-taped our instruments to the PVC. In January, we tossed the mooring off the side of a boat and marked the latitude and longitude from the boat's GPS. Other than marking the GPS, we had no other way to locate or retrieve these instruments - no surface buoy marking the surface, no pinger or acoustic release to help us find them, nothing. We returned, 7 months later, with a fantastic dive team on Skidaway's R/V Blanton. When the boat hit the right latitude and longitude, we dropped a mushroom anchor with a buoy off the side of the boat, then the dive team used that buoy line to head to the seafloor and search for our instruments. To my surprise and delight, the visibility was unusually good and the divers found the moorings at each of the 3 sites within minutes! They cut through the tape and zip ties and brought our instruments, and the precious acoustic data they hold, to the surface. Now it's time to analyze the data! |
AuthorErin Meyer-Gutbrod is an Assistant Professor at the University of South Carolina. Her lab researches human impacts to marine ecosysems. Archives
April 2024
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