The witch flounder or grey sole, Glyptocephalus cynoglossus , is common throughout the Gulf of Maine and also occurs in deeper areas on Georges Bank and along the shelf edge as far south as Cape Hatteras. Research vessel survey data suggest that the Gulf of Maine-Georges Bank population may be relatively discrete from populations in other areas. Spawning occurs in late spring and summer. The principal fishing gear used to catch witch flounder is the otter trawl.
Recreational catches are insignificant.
Amendment 9 established biomass rebuilding targets, and defines control rules which specify target fishing mortality rates and corresponding rebuilding time horizons. The goal of the management program is to reduce fishing mortality to levels which will allow stocks within the complex to initially rebuild above minimum biomass thresholds, and, ultimately, to remain at or near target biomass levels. Total landings peaked at more than 6,000 mt in 1971, declined to an annual average of 2,800 mt during 1973-1981, and then increased sharply to 6,700 mt in 1984. Landings then declined steadily to only 1,500 mt in 1990, the lowest value since 1964. Landings during 1991-1998 averaged 2,200 mt annually.