CHANGES IN THE SEX-RATIO AND SIZE AT MATURITY OF GAG, MYCTEROPERCA-MICROLEPIS, FROM THE ATLANTIC COAST OF THE SOUTHEASTERN UNITED-STATES DURING 1976-1995

Gag, Mycteroperca microlepis, is a large, slow-growing protogynous gro uper that probably makes annual migrations to specific locations to ag gregate for spawning. During 1976-82, male gag constituted 19.6% of th e sexually mature individuals taken during fishery-dependent and fishe ry-independent sampling along the southeast coast of the United States . A similar percentage of males was found in the Gulf of Mexico from 1 977 to 1980; however, males made up only 1.9% of the population in the Gulf of Mexico during 1992. To assess the current sex ratio of gag al ong the southeast U.S. coast. an emergency rule was enacted by the Dep artment of Commerce in January 1995 that required commercial vessels f rom North Carolina to southeast Florida to land gag with gonads intact . Histological examination of 2613 gonads of sexually mature gag colle cted from 18 January through 18 April 1995 revealed that 5.5% of the g ag from the southeast Atlantic were male. There was a weak trend indic ating that females reached maturity at a smaller size in 1994-95 than in 1976-82. Very few transitional specimens were collected during the spawning season. Most transitional individuals (79%) were taken during April through June immediately after the 1995 spawning season. Gag in spawning condition were landed during December through mid-May by fis hermen working offshore from North Carolina to southeast Florida. In a ddition, gag in spawning condition were taken during research cruises documenting the occurrence of spawning north of Florida (off South Car olina and Georgia at depths ranging from 49 to 91 m).