Biologia reprodutiva do Budião-Batata, Sparisoma frondosum (TELEOSTEI: LABRIDAE) capturados no litoral cearense

Abstract

Parrotfish, or budião, are a species of the Labridae family and play a fundamental role in reef and coastal environments in terms of algal control and carbonate production. Due to the potential impacts of fishing on this species, it is necessary to understand the reproductive biology of this group in the state of Ceará, in order to understand how local fishing is affecting its stock. Thus, the aim of this study was to determine the reproductive parameters of the potato budião (Sparisoma frondosum), a protogynous species, caught by the artisanal fleet off the coast of Ceará. The population of S. frondosum off the coast of Ceará showed a sex ratio of females to males of 1.15:1 (F:M), with no sex predominance. However, it was possible to notice significant differences between the sex ratios in the months of March, April, June and December, as well as in the length classes, with more abundant females in the higher length classes. There were no significant differences between standard lengths (U=4729.5, p=0.064) and total weights (U=4730.5, p=0.064). There were significant differences in the gonadosomatic indices (H=45.28; p=4.32x10^-6), with the months of April and May showing the highest values (1.054 and 0.558, respectively). Actively spawning specimens were observed in April and May, while actively sperming fish were caught in May and June. The standard length of first sexual maturity (L50) for S. frondosum was 18.4 cm for the grouped sexes, 19.0 cm for females and 17.4 cm for males. Average fecundity for the species was 65,383.61 oocytes, with oocyte diameter ranging from 14.01 to 555.33 μm. The species showed asynchronous ovocyte development, with multiple spawning in batches, and was able to reproduce throughout the year, despite showing reproductive peaks during the months of April and June. The early size of first sexual maturation for males may indicate the presence of primary males within the population, as well as a possible impact of fishing on the reproductive aspects of the species, a fact corroborated by the equal proportion of males and females, since a predominance of females is expected in protogynous species. It is hoped that these data will contribute to the conservation status of the species in the country and in the state for possible assessments of the species' population status. In addition, it fills an important gap for the species in Ceará, since the species is of significant ecological importance and its capture is currently focused on export.