Ecologia reprodutiva do peixe-donzela, Stegastes fuscus cuvier, 1830 (osteichthyes: pomacentridae) em arrecifes rochosos da praia de B?zios, Rio Grande do Norte, Brasil

• Main Author: Souza, Liliane de Lima Gurgel
• Other Authors: CPF:15644812472
• Format: Others
• Language: Portuguese
• Published: Universidade Federal do Rio Grande do Norte 2014
• Subjects: Reprodu??o; Stegastes fuscus; Arrecifes rochosos; ?ndice gonadossom?tico; Reproduction; Coastal rocky reefs; gonadosomatic index; CNPQ::OUTROS
• Online Access: http://repositorio.ufrn.br:8080/jspui/handle/123456789/12499

Made available in DSpace on 2014-12-17T14:02:02Z (GMT). No. of bitstreams: 1 LilianeLGS.pdf: 3221431 bytes, checksum: 94de7bf42be19a1c9a513aa1e36efe19 (MD5) Previous issue date: 2006-07-10 === Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior === The reproductive ecology of fish plays a key role both for rational exploitation methods and for protective measures of natural stocks. The purpose of this study was to analyze the reproductive aspects of the damsel-fish, Stegastes fuscus, during October 2004 to September 2005, in the coastal rocky reefs of B?zios Beach, N?sia Floresta, RN. Fish were captured using hooks and hand nets, during low tide. Reproduction was determined using sexual ratio, mean length of first maturation (L50), absolute fecundity and macroscopic characteristics of gonads. The following parameters were related to gonadosomatic index (GSI): condition factor (CF), hepatosomatic index (HSI), rain fall and temperature. In relation to sex distribution, it was observed that 78% were females and 22% were males. The L50 was 6.2 cm for females and 7.0 for males. Average fecundity was 6832 oocytes. Results showed that S. fuscus had better body condition in the months prior to spawning, particularly during initial and intermediate stages of maturation. Five stages of gonadal maturation were identified through macroscopic analysis: immature, in maturation, mature, spent and resting. The HSI was inversely related to the GSI. This was possibly due to the reproductive cycle of this species which was associated to the dry period of this region. During this period, low rain fall and high temperatures provide an propitious reproductive condition for the study species === A ecologia reprodutiva dos peixes ? fundamental na racionaliza??o dos m?todos de explora??o e na prote??o dos estoques naturais. O presente estudo analisou aspectos relacionados ? reprodu??o do peixe-donzela, Stegastes fuscus, durante o per?odo de outubro de 2004 a setembro de 2005, nos arrecifes rochosos da praia de B?zios, N?sia Floresta, RN. Os peixes foram capturados durante a mar? baixa utilizando anz?is e rede de m?o. A reprodu??o foi verificada mediante a propor??o sexual, o comprimento m?dio da primeira matura??o, a fecundidade absoluta e os caracteres macrosc?picos gonadais. Os seguintes par?metros foram relacionados ao ?ndice gonadossom?tico (IGS): fator de condi??o (FC), ?ndice hepatossom?tico (IHS), pluviosidade e temperatura. Em rela??o ? distribui??o por sexo de S. fuscus, 78% foram f?meas e 22% foram machos. O L50 foi 6,2 cm para as f?meas e 7,0 cm para os machos. A m?dia da fecundidade absoluta foi 6832 ov?citos. S. fuscus apresentou melhores condi??es corporais nos meses que antecederam a desova, principalmente nos est?dios inicial e intermedi?rio de matura??o gonadal. A partir de an?lises macrosc?picas das g?nadas, foram identificados cinco est?dios de matura??o gonadal: imaturo, em matura??o, matura??o, esgotado e repouso. O IHS demonstrou tend?ncia inversa ao IGS. Este fato pode estar relacionado ao ciclo reprodutivo da esp?cie, que foi relacionado ao per?odo de seca na regi?o. Neste per?odo, as menores precipita??es e as temperaturas elevadas conferem condi??es reprodutivas favor?veis para a esp?cie em estudo