This study was carried out to investigate the reproductive aspects of the flying fish, Hirundichthys affinis Günther, 1866 considering their importance in the fish production of the Rio Grande do Norte State, Brazil. Fish samples were collected from the Municipality of Caiçara do Norte, northern coast of the state, during the period of April, 1999 to April, 2000. The fish were measured, weighed, dissected and the gonads were examined to separate the sex and to determine the stage of maturation. Histological studies were done for microscopic characterization of the gonads. The results indicated that H. affinis had a sexual proportion of 1:1; condition factor was inversely related to the gonadosomatic index during the reproductive phase; and the highest for both sexes was registered during the breeding season. Males and females showed four devolopmental stages of the gonads: immature, initial maturation, mature and spent. Absolute fecundity varied from 4400 to 6400 oocytes, with a mean of 5400. The species presents total spawing and the spawing season occurred in the months of May and June. The rainy season preceeded the occurrence of breeding flying fishes in the coastal waters of Caiçara do Norte.
Flying fish; reproductive strategy; gonadal development