Maturation of Little Skate and Winter Skate in the Western Atlantic from Cape Hatteras to Georges Bank

Abstract

AbstractWe estimated the length and age of maturation in little skate Leucoraja erinacea and winter skate L. ocellata based on samples of 1,884 little skate and 1,153 winter skate ovaries collected from Cape Hatteras, North Carolina, to Georges Bank. Two levels of maturity were recognized: onset maturity, which marks the onset of the allocation of energy from somatic growth to reproduction; and “functional” maturity, which marks the point when mature oocytes are released. Size at maturation increased with latitude in little skate, 50% onset maturity occurring at 42.5, 43.0, and 46.5 cm (total length) and 50% functional maturity at 43, 44, and 46 cm for the mid‐Atlantic, southern New England–Georges Bank, and Gulf of Maine regions, respectively. Based on age estimates from previously published work, the age at which little skate achieve functional maturation ranged between 7.0 and 7.5 years for the U.S. northeast coast. In winter skate, no statistically significant regional differences in maturation rates were found. Size at 50% onset maturity was estimated to be 66 cm and at 50% functional maturity 76 cm for the U.S. northeast coast. In winter skate, onset maturity occurred at 9.5 years and functional maturity at 12.5 years. Thus, functional maturity in this species occurred 3 years after the onset of maturation, indicating that the species has a long adolescence before contributing offspring to the population.