Report of the Workshop on Trawl Warp Effects on Fishing Gear Performance. Marine Biological Laboratory, Woods Hole, Massachusetts, October 2-3, 2002

摘要

On 3 September 2002, in response to a concern raised by a member of the fishing industry, the trawl cables (warps) on the NOAA Ship ALBATROSS IV were inspected and found to have inaccurate 50-meter markings. That is, the marks were not exactly at true 50-meter intervals over the first 1,000 meters of the warps. The difference in marks from the true values ranged between less than 1 inch to 38.4 inches. Also, some of the marks were not evenly matched between the port and starboard cables. The cables were mismarked by the vendor upon installation in February 2000 and were used in eight bottom trawl surveys beginning with Winter 2000 and ending with Spring 2002. Thus, at times during these surveys, more cable may have been deployed on one side of the bottom trawl than on the other. The difference between the two warps is a matter of inches at shallower fishing depths but increases as more cable is set out. For example, when 100 meters (328 feet) of cable are deployed, the warp lengths differ by about 1 inch; when 300 meters (984 feet) are let out, the warp lengths differ by about 6 feet. Approximately 75% of the sampling tows accomplished in the bottom trawl surveys use 300 meters or less of cable.