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The Brazilian-endemic greenbeack parrotfish, Scarus trispinosus Valenciennes, 1840, is the largest herbivorous reef fish in the South Atlantic. Following the sharp decline of large carnivorous reef fishes, parrotfishes (Labridae: Scarinae) were progressively targeted by commercial fisheries in Brazil, resulting in a global population decline of 50% for S. trispinosus. Most of its remnant population is concentrated in the Abrolhos Bank, where the present study was conducted. We present novel information on age, growth and the reproductive cycle of S. trispinosus, based on 814 individuals obtained from commercial fisheries' landings and scientific collections, between 2010 and 2013. Sex ratio was biased toward females (1:8), and spawning occurred yearround with discrete peaks in February-March and June-December. Increment analysis indicated annual deposition of growth rings in otoliths, which presented 1-22 rings. The asymptotic length at which growth is zero (L1) was estimated from a Bayesian logistic regression at 85.28 cm, growth rate (K) at 0.14 year-1, and the theoretical age at zero size (t0) at 0.16. Subregional demographic structuring was detected, with predominance of slower-growing individuals in shallower inshore reefs and predominance of faster-growing and older individuals in deeper offshore sites. We demonstrate that S. trispinosus is highly vulnerable to over-exploitation due to its large size, long live and slow-growth, and review the management measures proposed since its Red List assessment in 2012. [ABSTRACT FROM AUTHOR]

The reproductive biology of Epinephelus morio (red grouper) and Mycteroperca bonaci (black grouper) were evaluated based on 533 specimens collected from artisanal fisheries landings in the Abrolhos Bank, Brazil, between May 2005 and September 2012. Sex ratio for the black grouper was 1:14 ( n = 155 females and 11 males; 26.1-147 cm TL) and 1:10 for the red grouper ( n = 334 females and 33 males; 15.0-96.0 cm TL). For both species, highest values of the gonadosomatic index (GSI) for females were recorded between July and October, indicating spawning during the austral winter. The length at first maturity (L) for females was estimated at 62.0 and 47.0 cm TL for the black and red grouper, respectively. Batch fecundity based on TL and TW ranged from 2 to 15.410 and 1.5 to 13.710 for the black and red grouper, respectively. Interviews with experienced fishers revealed that spawning seasons of both groupers are largely unrecognized. Results demonstrate a positive relationship between GSI peaks, lower temperatures and stronger winds. The information provided herein may help decision-making regarding fisheries management and conservation for E. morio and M. bonaci at various levels of governance in the Abrolhos Bank, the region with the largest and richest coralline reefs in the South Atlantic. [ABSTRACT FROM AUTHOR]

Background. The goliath grouper, Epinephelus itajara (Lichtenstein, 1822), is the largest Atlantic grouper. It has been the first marine fish subjected to a fishing moratorium in Brazil (since 2002). The aim of this study was to investigate basic biological aspects, particularly the diet and reproduction of this endangered species. We believe that our results, together with information already available in the literature, may be a foundation for new management and conservation strategies for this grouper in Brazil. Materials and Methods. Specimens were obtained from an artisanal fish landings collaborative monitoring program in the cities of Caravelas and Alcobaça, Abrolhos Bank, eastern Brazil. Because of the fishing moratorium, we relied on sporadic incidental captures from fishermen or donation from the law enforcement agencies. Diet and reproduction of the goliath grouper was evaluated based on 34 specimens obtained between May 2005 and September 2010. Results. Body size of 32 females ranged from 27.4 to 150.0 cm total length (TL) (mean 87.4 ± SD 34.8), while size of 2 males were 97.0 and 115.0 cm TL. Of these, 16 specimens (47%) were juveniles. Sex ratio was estimated as 1 : 16 (males to females). Two developing females were recorded, one obtained in February 2006 and another in January 2007. The length of first maturation (L50) for females was estimated at 105.64 cm and the length where 100% of individuals are mature (L100) at 126.0 cm TL. A total of 34 stomachs were analyzed, six of them were empty. Teleosts and decapods dominated the diet. The major food items of mangrove-associated fish were decapods Callinectes sp., while the coral reef-associated fish ingested mainly the boxfish Acanthostracion sp. The most important item for juveniles was Callinectes sp., while Acanthostracion sp. was the most important item for adults. Conclusion. We suggest that the goliath grouper moratorium in Brazil should be maintained for a relatively long time frame--more than four decades. [ABSTRACT FROM AUTHOR]