Island in the Stream: Oceanography and Fisheries of the Charleston Bump

Geographic Distribution of Longline Effort and Swordfish Discard Rates in the Straits of Florida and Oceanic Waters of the Continental Shelf, Slope, and Blake Plateau Off Georgia and the Carolinas from 1991 to 1995

Jean Cramer


Abstract.—The Gulf Stream off the east coasts of Florida, Georgia, and the Carolinas is one of the U. S. pelagic fishery regions in which particularly high swordfish discard rates were reported after a regulation limiting the landings of swordfish less than 25 kg whole weight went into effect in 1991. Swordfish Xiphias gladius fishing and catch locations from mandatory longline logbooks for the years 1991 through 1995 were used to explore the distribution patterns of swordfish discard rates in this region. Every 0.1 degree square of latitude and longitude was assigned a discard rate category (very high, moderate, low, none) for each month of the year based on the percentage of the swordfish catch that was discarded in that month over the five year period. Swordfish discard rates varied with latitude and season. The greatest seasonal changes were seen off the Carolinas where discard rates increased in the fall along with changes in fishing patterns.