Aspects of fishing and reproduction of the black grouper Mycteroperca bonaci (Poey, 1860) (Serranidae: Epinephelinae) in the Northeastern Brazil

Abstract

The reproductive biology of the black grouper Mycteroperca bonaci, caught by artisanal fishermen using hook and line or compressor -assisted spear fishing, from the Northeastern shelf and oceanic banks of Brazil, was studied between August 1996 and April 1998. The sexual pattern, gonadal development, the spawning mode and seasonality were investigated. The gonadal stages indicated that this species is a protogynous hermaphrodite and that transition from female to male occurs through simultaneous re-absorption of ovarian tissue and proliferation of testicular tissue in the gonads. The specie is a multiple spawner and frequency analysis of gonadal stages and gonadosomatic index suggest that the spawning season occurs between April and September. Considerations about the fisheries, related to size structure of fishes caught, were based on length frequency distribution. The phenomenon of "correção" was described based on ethnobiology studies and informations from the Northeast Fisheries Statistics Bulletin of the Brazilian Environmental Institute (IBAMA). The phenomenon of the "correção" undergone by Mycteroperca bonaci seems to be a Southward chain reaction (of the State of Ceará to Bahia) and is a feeding aggregation.A biologia reprodutiva do sirigado Mycteroperca bonaci, capturado na pesca artesanal com uso de linha e arpão, na plataforma e bancos oceânicos do nordeste do Brasil, foi estudada entre agosto de 1996 e abril de 1998. O padrão sexual, o desenvolvimento gonadal e o modo e período de desova foram investigados. Os estágios gonadais indicam que esta espécie é hermafrodita protogínica e que a transição de fêmea para macho ocorre simultaneamente através da reabsorção do tecido ovariano e da proliferação do tecido testicular nas gônadas. A espécie apresenta desova múltipla e a análise da freqüência dos estágios gonadais e do índice gonadassomático sugerem que a desova ocorre entre abril e setembro. Considerações sobre a pesca, relacionada à estrutura de tamanho dos peixes capturados, foram baseadas na distribuição de freqüência de comprimentos. O fenômeno da correção foi descrito baseado em estudos etnobiológicos e informações dos Boletins Estatísticos da Pesca do Instituto Brasileiro do Meio Ambiente e dos Recursos Naturais Renováveis (IBAMA). A correção realizada por Mycteroperca bonaci parece ser um efeito em cadeia, que inicia no norte (Ceará) e termina no sul (Bahia), e corresponde a uma agregação alimentar.

Spawning patterns of commercially important reef fish (Lutjanidae and Serranidae) in the tropical western South Atlantic

“…C. fulva and E. morio begin sexual transition at approximately 18 and 35 cm SL in Abrolhos (22 and 45 cm TL in the Caribbean and the southern United States) (Thompson and Munro, 1974;Burgos et al, 2007). However, Mycteroperca bonaci begins changing sex in Abrolhos only after reaching 40 cm SL, which differs from observations from the southern Gulf of Mexico (Brulé et al, 2003: 85 cm FL) but is closer to the smallest size for transitional M. bonaci from northeastern Brazil (64 cm FL) that was reported by Teixeira et al (2004). In this case, histological corroboration of our results will be necessary before this geographical variation in size at the time of sexual transition can be confirmed.…”

“…For M. bonaci, which is the only tropical grouper species for which there are spawning data from Brazil, Teixeira et al (2004) recorded coincident spawning peaks between 2 and 10 o S, with females being fertile between August and September. The breeding seasons of these three serranids in Brazil largely correspond to those that have been recorded in the Northern Hemisphere (Smith, 1961;Moe, 1969;Munro, 1983;García-Cagide and García, 1996;Brulé et al, 1999;Giménez-Hurtado et al, 2003;Burgos et al, 2007), where they also tend to spawn from late autumn to early spring (December to April).…”

“…Further assessments in this area are underway to confirm the existence and the characteristics of this potential spawning aggregation site. With the exception of jewfish spawning aggregations in Santa Catarina State (Gerhardinger et al, 2009), there is only speculation on the timing and location of snapper-grouper spawning aggregations in Brazil (Teixeira et al, 2004;Costa et al, 2003Costa et al, , 2005.…”

“…A similar exploitation situation has been reported for northeastern Brazil between 4 and 13°S (Frédou et al, 2009a, b). Grouper stocks have never been assessed in Brazil, but their state may be even worse than that of snappers (Teixeira et al, 2004).…”

DNA barcoding approaches for fishing authentication of exploited grouper species including the endangered and legally protected goliath grouper <i>Epinephelus itajara</i>

“…Traditional knowledge about the ecology and habits of the grouper among local, small-scale fishermen, has been very important for the conservation of the goliath grouper in Brazil (Hostim-Silva et al 2005, Gerhardinger et al 2009). Other species of grouper, including the dusky (formerly Mycteroperca marginata sensu Craig and Hastings 2007), red (Epinephelus morio) and black (M. bonaci), are also exploited, yet their conservation receives less attention worldwide (Gimenez-Hurtado et al 2005, Machado et al 2003, Teixeira et al 2004, Gerhardinger et al 2006, Freitas et al 2011. Therefore, they may suffer even greater extinction risks.…”