Age, Growth, and Sex Ratio of American Eels in Brackish-Water Portions of a South Carolina River

American eels Anguilla rostrata (yellow phase; N = 462) collected from brackish-water portions (range of salinity: 0–23‰) of the Cooper River, South Carolina, ranged in length from 26.0 to 68.7 cm and in weight from 32 to 767 g. The length-weight relationship is log10W = -5.85 + 3.07 log10L; W = wet weight (g) and L = total length (mm). Age estimates (inland years) from 442 pairs of otoliths indicated a mean age of 4.3 years and range of 1–12 years. Growth of American eels from brackish-water areas of the Cooper River was faster than growth of the species from northeastern United States and Canada. American eels from this southern habitat appear to migrate back to sea after ages 6–7, sooner than eels from northern locations. Histological examination of gonads from 458 specimens revealed that females outnumbered males 23 to 1. These results were consistent with most previous investigations and suggest that females dominate American eel populations in brackish-water and freshwater habitats in North America. Received December 21, 1982 Accepted July 2, 1984