Age, growth, reproduction and management of Southwestern Atlantic's largest and endangered herbivorous reef fish, Scarus trispinosus Valenciennes, 1840.

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 year-round 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 (L ∞) 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 (t 0) 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.

Dynamics of coral reef benthic assemblages of the Abrolhos Bank, eastern Brazil: inferences on natural and anthropogenic drivers.

The Abrolhos Bank (eastern Brazil) encompasses the largest and richest coral reefs of the South Atlantic. Coral reef benthic assemblages of the region were monitored from 2003 to 2008. Two habitats (pinnacles' tops and walls) were sampled per site with 3-10 sites sampled within different reef areas. Different methodologies were applied in two distinct sampling periods: 2003-2005 and 2006-2008. Spatial coverage and taxonomic resolution were lower in the former than in the latter period. Benthic assemblages differed markedly in the smallest spatial scale, with greater differences recorded between habitats. Management regimes and biomass of fish functional groups (roving and territorial herbivores) had minor influences on benthic assemblages. These results suggest that local environmental factors such as light, depth and substrate inclination exert a stronger influence on the structure of benthic assemblages than protection from fishing. Reef walls of unprotected coastal reefs showed highest coral cover values, with a major contribution of Montastraea cavernosa (a sediment resistant species that may benefit from low light levels). An overall negative relationship between fleshy macroalgae and slow-growing reef-building organisms (i.e. scleractinians and crustose calcareous algae) was recorded, suggesting competition between these organisms. The opposite trend (i.e. positive relationships) was recorded for turf algae and the two reef-building organisms, suggesting beneficial interactions and/or co-occurrence mediated by unexplored factors. Turf algae cover increased across the region between 2006 and 2008, while scleractinian cover showed no change. The need of a continued and standardized monitoring program, aimed at understanding drivers of change in community patterns, as well as to subsidize sound adaptive conservation and management measures, is highlighted.

Feeding ecology of two sympatric species of large-sized groupers (Perciformes: Epinephelidae) on Southwestern Atlantic coralline reefs

Red and black groupers are large-bodied opportunistic ambush predators commonly found in Southwestern Atlantic tropical reefs. We investigated the diet of both species in order to detail ontogenetic, spatial and temporal trends, and to assess the extent of overlap in resource use between these two sympatric predators on the Abrolhos Bank, Brazil. Decapods and fishes were the main food items of Epinephelus morio while fishes were the main prey of Mycteroperca bonaci. Both diets were significantly influenced by body size and habitat, but only smaller individuals of E. morio feed almost exclusively on crustaceans. While the two groupers rely on many of the same prey types, coexistence may be facilitated by E. morio feeding more heavily on crustaceans, particularly the blackpoint sculling crab Cronius ruber, while black grouper take comparatively few crustaceans but lots of fish prey. Predators like red and black groupers could trigger indirect effects in the community and influence a large range of ecological processes, such as linkages between top and intermediate predators, and intermediate predators and their resources.(AU)

A garoupa e o badejo-verdadeiro são predadores oportunistas de grande porte, com estratégia de emboscada, comumente encontrados em recifes tropicais do Atlântico Sul. A dieta das duas espécies foi investigada, avaliando influências ontogenéticas, espaciais e temporais, assim como a sobreposição no uso de recursos entre estes dois predadores co-orrentes no Banco dos Abrolhos, Brasil. Decápodes e peixes foram os principais itens alimentares de Epinephelus morio, enquanto que os peixes foram as principais presas de Mycteroperca bonaci. Ambas as dietas foram significativamente influenciadas pelo tamanho corporal e habitat, mas apenas indivíduos menores de E. morio alimentaram-se quase que exclusivamente de crustáceos. Como as duas espécies utilizam muitas presas semelhantes, a coexistencia parece ser facilitada pelo fato de E. morio se alimentar principalmente de crustáceos, particularmente do caranguejo Cronius ruber, enquanto que o badejo-verdadeiro consome relativamente poucos crustáceos e grande quantidade de peixes. Predadores como as espécies estudadas podem causar efeitos indiretos na comunidade e influenciar uma grande variedade de processos ecológicos, como conexões entre predadores de topo e intermediários e predadores intermediários e seus recursos.(AU)

Fisheries monitoring in Babel: fish ethnotaxonomy in a hotspot of common names

The lack of a long term, comprehensive and reliable fisheries statistics system is a major impediment to fisheries management in Brazil. Fishing is one of the main activities throughout the country's coast, with predominance of small-scale, artisanal, multigear, and multispecies captures that are landed in a pulverized network of coastal villages. Brazil is also a hotspot of common names, another feature that challenges artisanal fisheries' monitoring. We combined taxonomic and ethnobiological information to support the implementation of an artisanal fisheries' monitoring program under the co-management framework of a Marine Extractive Reserve in Bahia State, Northeastern Brazil. We surveyed 141 fishing landings, recording 86 fish species (43 families) and 52 correspondences 1:1 between local and scientific names. Broad folk categories had an average of 5.1 specific names, with "cação" (shark) being the category with more specific names (24 names to six biological species). With the exception of species that make up the bycatch captured by shrimp trawling, fisherfolks are able to identify commercially important species from both fresh specimens and photos. Common names can be reliably used in fisheries monitoring programs, and their usage facilitates the participation of fisherfolks in surveys based on voluntary or compulsory declarations of captures.

A falta de um sistema compreensivo e confiável de estatísticas pesqueiras em longo prazo é um dos maiores dificultadores da gestão pesqueira no Brasil. A pesca é uma das principais atividades ao longo da costa do país, com predominância de capturas artesanais de pequena escala, envolvendo múltiplas artes e espécies, além de desembarques realizados em uma rede pulverizada de localidades costeiras. O Brasil também possui grande riqueza de nomes comuns, outra característica que complica o monitoramento da pesca artesanal. No presente trabalho, combinamos informações taxonômicas e etnobiológicas para apoiar a implementação de um programa de monitoramento da pesca artesanal recifal e costeira sob o arcabouço de cogestão de uma Reserva Extrativista Marinha no estado da Bahia, Nordeste do Brasil. Foram amostrados 141 desembarques e registradas 86 espécies de peixes (43 famílias), com 52 correspondências 1:1 entre nomes locais e científicos. Categorias de nomes comuns genéricos tiveram uma média de 5,1 nomes específicos locais, com "cação" sendo aquela com mais nomes específicos (24 nomes para seis espécies biológicas). Excetuando-se as espécies capturadas como fauna acompanhante do arrasto-de-camarão, observamos que os pescadores são capazes de identificar as espécies comercialmente importantes tanto a partir de espécimes quanto de fotografias. Os nomes comuns podem ser usados com segurança em programas de monitoramento de pescarias de pequena escala, sendo que seu uso facilita a participação dos pescadores em levantamentos baseados em declarações de captura, sejam elas voluntárias ou compulsórias.

Age and growth of the dog snapper Lutjanus jocu (Bloch & Schneider, 1801) in Abrolhos Bank, Northeastern Brazil

We determined the age and growth of the dog snapper (Lutjanus jocu), caught in the region of Abrolhos Bank, Bahia State, by the fishermen from coastal communities of Prado, Alcobaça, Caravelas, and Nova Viçosa. We examined 205 sectioned otoliths of fish caught by harpoon, longline, hand line, and gill nets (14.5 to 79.5 cm fork length). The formation of each ring was considered annual. The sectioned otoliths showed between 0 and 29 rings. Nearly half of the analyzed specimens had between 0 and 7 rings (88 of 205). Fish caught with nets in the estuarine region were the juvenile, while fish caught with lines and harpoons were the oldest. Two von Bertalanffy growth models were fitted to length-at-age data: one assuming constant variance of length-at-age (SVB) and another assuming constant coefficient of variation, i.e. variance increasing as a function of average size (CVVB). The SVB estimates were Loo = 87.82 cm, K = 0.10, and t0 = -1.486 and the CVVB estimates were Loo = 117.60 cm, K = 0.06, and t0 = -2.470. The largest Loo values estimated by the CVVB model are supported by reports from the literature of larger animals occurring in the deeper outer shelf of Abrolhos Bank. Growth parameters were also estimated for males and females separately (SVB model) (Loo = 92.80 cm, K = 0.099, and t0 = -1.680 for males, and Loo = 82.10 cm, K = 0.105, and t0 = -1.570 for females).

Foi determinada a idade e o crescimento do dentão (Lutjanus jocu) capturado na região do Banco dos Abrolhos, Bahia, pelos pescadores das comunidades costeiras de Prado, Alcobaça, Caravelas e Nova Viçosa. Foram examinados 205 otólitos seccionados de peixes capturados por arpão, espinhel de fundo, linhas e redes de emalhe (14,5-79,5 cm comprimento furcal). A formação de cada anel foi considerada anual. Os otólitos seccionados apresentaram entre 0 e 29 anéis. Cerca de metade dos espécimes analisados teve entre 0 e 7 anéis (88 de 205). Os peixes capturados com redes na região estuarina foram os mais jovens enquanto os peixes capturados com arpões e linha foram os mais velhos. Dois modelos de crescimento de von Bertalanffy foram ajustados aos comprimentos individuais: um assumindo variância constante do comprimento em cada idade (SVB) e outro assumindo coeficiente de variação constante, isto é variância aumentando em função do tamanho médio (CVVB). As estimativas SVB foram (Loo = 87,82 cm, K = 0,105 e t0 = -1,486) e as estimativas CVVB foram Loo = 117,60 cm, K = 0,060 e t0 = -2,470). Os maiores valores de Loo estimados pelo modelo CVVB são sustentados por relatos da literatura de grandes animais encontrados em áreas mais profunda do Banco dos Abrolhos. Os parâmetros de crescimento também foram estimados para machos e fêmeas separadamente (modelo SVB), (Loo = 92,80 cm, K = 0,099 e t0 = -1,680 para machos e Loo = 82,10 cm, K = 0,105 e t0 = -1,570 para fêmeas).