Sexual dimorphism in yellow European eels, Anguilla anguilla (L.)

Sexual dimorphism in yellow eels, Anguilla anguilla (L.). was studied to clarify the differences between sexes. The focus was on the relationship between length/weight and sex. Three samples of eels, grown in captivity in different places in Israel, were studied. Females were significantly lighter than undifferentiated eels in the length range 33-47 cm. The regression coefficient did not differ significantly between females and undifferentiated eels. Sex induction, by a single injection of human chorionic gonadotropin, resulted in a higher loss of body weight during differentiation into the female than into the male.