Surveys of Derelict Crab Pots on Diamondback Terrapin Populations in North Carolina Waters – 2008

Survey the distribution of derelict crab pots along the North Carolina coastline using side scan sonar, aerial surveys, and global positioning systems.

Project Abstract

Researchers at the NOAA Southeast Fisheries Science Center planned to locate, retrieve, inventory, and dispose of 100 traps at multiple sites along the North Carolina coast: Currituck, Croatan, Pamlico, lower Albemarle, Core, Bogue, Topsail, and Masonboro Sounds.  Survey sites ranged from tidal mesohaline (salinity range 5-18 parts per thousand (ppt)) to tidal polyhaline (salinity range 18-30 ppt), and were accessed by public and private boat ramps using shallow-draft boats equipped with side-scanning sonar and global positioning systems (GPS).

Aerial, side scan sonar, and on-boat visual surveys were conducted, but few traps were removed due to poor conditions at sea and minimal on-board capacity to retrieve derelict pots.  Many of the pots found were either cut open or crushed to ensure these pots would not continue to “ghost fish”.  Of the pots located and recorded (n= 326), 47% were on land or within the upper marsh and above the mean high tide line, 19.9% were in the inter-tidal zone, and 32.5% were in areas where they were permanently covered with water even during low tide (6 inches to 12 feet). Many of these were in or adjacent to boating channels or the Intracoastal Waterway. Of the submerged traps, 77.35% were first detected with the side scan sonar, and most of these would have remained undetected without the use of side scan sonar.  Several outreach and education events and tools were employed during this research effort in local communities.

NOAA Marine Debris Program Project

1/1/2008 to 9/30/2009

Status: Closed

Location: [Southeast], [North Carolina]

Latitude/Longitude: 35.192427, -76.093518