Ghost Net Survey Completed

Contact: Jim Churnside

ETL scientists, collaborating with Airborne Technologies, Inc. and the National Marine Fisheries Service (NMFS), just finished a survey of marine debris in the subtropical convergence zone in the north Pacific. Using data from several satellites, the convergence was tracked through the winter by the NOAA Satellite and Information Service (NESDIS) and NMFS scientists. This information was combined with current satellite data to determine the most likely areas to find aggregations of debris. One of the NOAA P3 aircraft was directed to these areas in a series of three flights (March 27th and 29th and April 3rd) out of Honolulu to determine if there was debris in these areas. Visual observations and an electronic imaging system with automated pattern recognition were both used on the flights.

The flights confirm that these convergence regions contain high densities of marine debris, including many ghost nets. About two thousand individual pieces of debris were seen. These included at least 100 that were identified as nets or pieces of net. One of these was 200-300 m of drift net with floats intact. A number were balls of net up to 10 m across. The data collected are being analyzed to estimate densities and to determine what satellite data are most effective in predicting the locations of the highest densities.

Based on the success of these flights, planning is underway to develop a cost-effective removal effort. These plans include transition from manned flights to unmanned aerial vehicles using improved pattern recognition. A pilot project for at-sea removal could begin as early as next year.

More Information

• Ghost Nets Program