Reef fishes biodiversity and conservation at the largest Brazilian coastal Marine Protected Area (MPA Costa dos Corais)

Abstract Coral reefs harbor one of the largest fish biodiversity on earth; yet information on reef fishes is still absent for many regions. We analyzed reef fish richness, distribution, and conservation on the largest Brazilian multiple use coastal MPA; which cover a large extent of coral reefs at the SWA. A total of 325 fish species have been listed for MPA Costa dos Corais, including Chondrichthyes (28 species) and Actinopterygii (297). Fish species were represented by 81 families and the most representative families were Carangidae (23 species), Labridae (21) and Gobiidae (15). The MPA fish richness represented 44% of all recorded fish species of the Southwestern Atlantic Ocean (SWA) highlighting the large-scale importance of this MPA. A total of 40 species (12%) are registered at Near Threatened (NT), Vulnerable (VU), Endangered (EN) or Critically Endangered (CR). This study reinforces the importance of MPA Costa dos Corais on reef fish biodiversity and conservation and emphasize the urgent need of conservation strategies.

Resumo Os recifes de coral abrigam uma das maiores biodiversidades de peixes do planeta; no entanto, as informações sobre peixes de recife ainda estão ausentes em muitas regiões. Analisamos a riqueza, distribuição e a conservação de peixes recifais na maior Área de Proteção Ambiental (APA) costeira de uso múltiplo do Brasil; área que possui grande extensão de recifes de corais no SWA. Um total de 325 espécies de peixes foram listadas para APA Costa dos Corais, incluindo Chondrichthyes (28 espécies) e Actinopterygii (297). As espécies de peixes foram representadas por 81 famílias e as famílias mais representativas foram Carangidae (23 espécies), Labridae (21) e Gobiidae (15). A riqueza de peixes da APA representou 44% de todas as espécies de peixes registradas no Oceano Atlântico Sudoeste (SWA), destacando a importância em grande escala desta APA. Um total de 40 espécies (12%) estão registradas como Quase Ameaçada (NT), Vulnerável (VU), Em Perigo (EN) ou Criticamente Em Perigo (CR). Este estudo reforça a importância da APA Costa dos Corais na biodiversidade e conservação dos peixes recifais e enfatiza a necessidade urgente de estratégias de conservação.

Fish community structure as an indicator of the ecological significance: A study from Ulhas River Estuary, Western coast of India

Aim: The present study was aimed to analyze the ecological significance of Ulhas River estuary of the western coast of India using the taxonomic, functional and conservation aspects, and also to record an updated data base on the estuarine community structure.Methodology: Ichthyo faunal diversity was assessed by experimental fishing conducted at 3 selected stations using single day dolnets of code end mesh size of 10mm, from September 2017 to August 2018. The diversity of fish species was recorded considering the most relevant taxonomic classification data and further supplemented by the information pertaining to ecological roles played by the individual species (using guild approach) and the IUCN- conservation status. Results: There were 105 species, belonging to 4 classes, 19 orders, 44 families and 75 genera, recorded from Ulhas River Estuary. The class: Actinopterygii was the most diverse taxa, (including 12 orders, 32 families and 55 genera) among the total ichthyofauna reported. Order Perciformes was the most representative order of the class (40 species, 31 genera and 17 families), followed by Decapoda (21species, 8 genera and 6 families). Based on the estuarine usefunctional guild categorization, 51.42 % of the species were marine migrants, followed by amphidromous species (21.9%). Zoobenthivores (29.41%) was found to be the most dominant feeding guild followed by omnivores (19.6%). Based on the IUCN Red List, 53.33% of the fish species observed from Ulhas River Estuary were categorized as “Not Evaluated”, and 7% were “Data Deficient”, signifying the lack of information on biological aspects of the species along Indian waters. Tenualosa toli marked its presence under threatened category (Vulnerable) from Ulhas River Estuary. Interpretation: The abundance of marine migrants as well as the amphidromous species in the estuary signifies the use of this ecosystem for the nursery function of commercially important marine fisheries resources. Increased proportion of “Not Evaluated” and “Data Deficient” categories in the context of high level of anthropogenic stress demands for more updated documentation of the biodiversity and periodic changes in its ecological structure for formulating and implementing effective ecosystem-based management programs for such sensitive estuarine ecosystems.

Seasonal composition, abundance and biomass of the subestuarine fish assemblage in Solís Chico (Río de la Plata estuary, Uruguay) / Composição, abundância e biomasa sazonal da assembleia de peixes no subestuário do Solís Chico (Estuário do Río de la Plata, Uruguay)

Abstract The large estuaries can present long narrow branches called subestuaries or tidal creeks. These types of subsystems are distributed along the Uruguayan coast of the Río de la Plata estuary and are very important as nursery and refuge areas for fish. For the first time, the seasonal composition and abundance of the fish community of the Solís Chico subestuary was studied by using beach and gill nets. Fourteen species, mainly euryhaline (86%) presented a significant representation of juvenile stages. The fish community was dominated by Odontesthes argentinensis, Platanichthys platana, Mugil liza, Brevoortia aurea, Micropogonias furnieri and Paralichthys orbignyanus, similar to adjacent subestuaries. While Micropogonias furnieri and B. aurea were the most abundant species, some other species were rarely caught. A seasonal variation of the fish assemblage abundance was detected, with higher values in autumn showing a positive correlation with temperature. Species that complete their life cycle in the Río de la Plata estuary, some of which are relevant to fisheries (64% of the analyzed species) were captured in the Solís Chico subestuary. The importance of this environment as a transitional system for some estuarine fish species is advised.

Resumo Os grandes estuários podem apresentar longos ramos estreitos chamados subestuários e riachos de maré. Estes subsistemas estão distribuídos ao longo da costa uruguaia no estuário do Río de la Plata e são muito importantes como áreas de reprodução e refúgio para os peixes. Pela primeira vez, a composição sazonal e abundância da comunidade de peixes do subestuário Solís Chico foi estudada usando redes de arrasto de praia e rede de emalhar. Quatorze espécies com predominância das eurialinas foram capturadas, havendo uma representação significativa das fases juvenis e espécies alvo para a pesca. A comunidade de peixes foi dominada por Odontesthes argentinensis, Platanichthys platana, Mugil liza, Brevoortia aurea, Micropogonias furnieri e Paralichthys orbignyanus, semelhante aos subestuários adjacentes. Enquanto, M. furnieri e B. aurea foram as espécies com maior número de individuos. Solís Chico apresentou espécies exclusivas com baixa abundância e ocorrência. Foi verificada uma variação sazonal da abundância de peixes, com valores maiores no outono, mostrando uma correlação positiva com a temperatura. Algumas espécies relevantes para a pesca que completam seu ciclo de vida no estuário do Río de la Plata foram capturadas (64% das espécies estudadas) no subestuário Solís Chico, indicando a importância deste ambiente como um sistema transitório para algumas espécies estuarinas de peixes.

Spatial variations in fish assemblage structure in a southeastern Brazilian reservoir / Variações espaciais na estrutura das assembléias de peixes em um reservatório do sudeste do Brasil

Abstract We assessed the fish assemblage structure and composition of Nova Ponte Reservoir (Araguari River, Upper Paraná Basin, Brazil). We observed significant differences in abundance (p = 0.0003), richness (p = 0.0005) and diversity (p = 0.02) between lacustrine and riverine zones of the reservoir. Nine species were significantly more abundant in the riverine region: Astyanax altiparanae, Astyanax gr. fasciatus, Galeocharax knerii, Hoplias intermedius, Hypostomus sp., Leporinus friderici, Leporinus obtusidens, Pimelodus maculatus and Schizodon nasutus. The results indicated a longitudinal gradient in the composition and abundance of fishes in Nova Ponte Reservoir, reinforcing the importance of freely flowing riverine reaches for conserving native neotropical ichthyofauna and reflecting the strong adaptation of these species to riverine systems.

Resumo Este estudo avaliou a assembléia de peixes do reservatório de Nova Ponte (rio Araguari, bacia do Alto Paraná, Brasil), em termos de estrutura e composição. Foram observadas diferenças significativas na abundância (p = 0.0003), riqueza (p = 0.0005) e diversidade (p = 0.02) entre as zonas lacustres e fluviais do reservatório. Nove espécies foram mais abundantes na região fluvial: Astyanax altiparanae, Astyanax gr. fasciatus, Galeocharax knerii, Hoplias intermedius, Hypostomus sp., Leporinus friderici, Leporinus obtusidens, Pimelodus maculatus and Schizodon nasutus. Os resultados indicaram a existência de um gradiente longitudinal na composição e abundância de peixes no reservatório de Nova Ponte. Estes padrões reforçam a importância de trechos fluviais livres de barramentos para a conservação da ictiofauna neotropical nativa e refletem a forte adaptação dessas espécies aos sistemas fluviais.

Peces arrecifales someros en el islote rocoso La Viuda, Golfo Dulce, Costa Rica / Shallow reef fishes around "La Viuda" rocky islet, Golfo Dulce, Costa Rica

Resumen Los arrecifes rocosos proveen una alta diversidad de organismos. Se presentaron cambios en la estructura de la comunidad íctica a lo largo de la estación climática y la acción del oleaje. Este estudio evaluó la diversidad y la abundancia de los peces del arrecife rocoso La Viuda, Golfo Dulce, Costa Rica (8°37'33" N - 83°14'08" W). Los peces fueron estudiados con el método de Bohnsack y Bannerot comparando las estaciones seca y lluviosa, las zonas protegidas y expuestas al oleaje usando índices ecológicos. El total de especies fue 28, las familias más abundantes fueron Pomacentridae y Labridae. La diversidad de Shannon-Wiener resultó entre 1,1 y 1,73 nits/ ind. El índice de Pielou en La Viuda fue 0.43. Se encontró mayor diversidad de especies en la época seca y en la zona protegida al oleaje.

Abstract Rocky reefs maintain a high diversity of organisms. Differences in fish community could be expected by seasonal events and wave action on rocky reefs. I studied "La Viuda" rocky islet, Golfo Dulce, CostA Rica (8°37'33" N - 83°14'08" W) with Bohnsack and Bannerot visual census methods four times between February and December 2002. I identified 28 species and the most abundant families were Pomacentridae and Labridae. Shannon-Wiener diversity was between 1.1 and 1.73 nits/ind., and Pielou 0.43. There is a higher diversity in the dry season and in areas protected from wave action. Rev. Biol. Trop. 63 (Suppl. 1): 329-338. Epub 2015 April 01.

Checklist of tidepool fishes from Jericoacoara National Park, southwestern Atlantic, with additional ecological information / Inventário dos peixes de poças de mare do Parque Nacional de Jericoacoara, Atlântico sudoeste, com informações ecológicas adicionais

Ichthyofauna from 29 tidepools in Jericoacoara National Park (Ceará State, Brazil) was sampled. A total of 733 fishes, comprising 16 species belonging to 12 families, was collected. The three most abundant species were the frillfin goby Bathygobius soporator, the sergeant-majorAbudefduf saxatilis and the molly miller Scartella cristata. An invasive species from the Indo-Pacific, the Muzzled blenny Omobranchus punctatus, was also recorded. The known geographic distribution of the blenny Hypleurochilus fissicornis was extended approximately 2,500 km northward. These findings highlight the lack of knowledge of the rocky intertidal ecosystems along the Brazilian coast, an area that needs more sampling effort and ecological data.

Um total de 733 espécimes de peixes, pertencentes a 16 espécies (12 famílias), foi capturado em 29 poças de maré no Parque Nacional de Jericoacoara (Ceará, Brasil). As espécies mais numericamente abundantes foram o amboré Bathygobius soporator, o sargentinho Abudefduf saxatilis e o macaco-verdeScartella cristata. Uma espécie invasora originária do Indo-Pacífico, Omobranchus punctatus, foi registrada para a área. A ocorrência de Hypleurochilus fissicornis permitiu expandir sua distribuição geográfica em cerca de 2.500 km ao norte. Esses resultados demostram que diversos aspectos relacionados a ictiofauna do ecossistema entremarés em substrato consolidado ainda permanecem pouco estudados no Brasil, e portanto, mais levantamentos da biodiversidade e dados ecológicos são necessários.

Bomb-cratered coral reefs in Puerto Rico, the untold story about a novel habitat: from reef destruction to community-based ecological rehabilitation / Los arrecifes de coral con craters-bomba en Puerto Rico, la historia no contada sobre un hábitat inusual: desde la destrucción de arrecifes hasta la rehabilitación ecológica basada en la comunidad

Ecological impacts of military bombing activities in Puerto Rico have often been described as minimal, with recurrent allegations of confounding effects by hurricanes, coral diseases and local anthropogenic stressors. Reef craters, though isolated, are associated with major colony fragmentation and framework pulverization, with a net permanent loss of reef bio-construction. In contrast, adjacent non-bombarded reef sections have significantly higher benthic spatial relief and biodiversity. We compared benthic communities on 35-50 year-old bomb-cratered coral reefs at Culebra and Vieques Islands, with adjacent non-impacted sites; 2) coral recruit density and fish community structure within and outside craters; and 3) early effects of a rehabilitation effort using low-tech Staghorn coral Acropora cervicornis farming. Reef craters ranged in size from approximately 50 to 400m² and were largely dominated by heavily fragmented, flattened benthos, with coral cover usually below 2% and dominance by non-reef building taxa (i.e., filamentous algal turfs, macroalgae). Benthic spatial heterogeneity was lower within craters which also resulted in a lowered functional value as fish nursery ground. Fish species richness, abundance and biomass, and coral recruit density were lower within craters. Low-tech, community-based approaches to culture, harvest and transplant A. cervicornis into formerly bombarded grounds have proved successful in increasing percent coral cover, benthic spatial heterogeneity, and helping rehabilitate nursery ground functions.

Los impactos ecológicos de las actividades militares de bombardeos en Puerto Rico se han descrito a menudo como mínimos, con recurrentes denuncias al confundir efectos por huracanes, enfermedades de corales y estresores antropogénicos locales. Los cráteres de arrecife, aunque aislados, están relacionados con una alta fragmentación de la colonia y pulverización del contorno, con una pérdida neta permanente de arrecife en bio-construcción. En contraste, secciones adyacentes de arrecife no bombardeado tienen mayor biodiversidad y mayor relieve espacial bentónico. Comparamos las comunidades bentónicas en cráteres-bomba de arrecifes de coral con 35-50 años de antigüedad en las islas de Vieques, Puerto Rico, en comparación con los sitios adyacentes no impactados; 2) la densidad de reclutamiento de coral y estructura de la comunidad de peces dentro y fuera de los cráteres; y 3) impactos preliminares de un esfuerzo de rehabilitación basado en la comunidad arrecifal usando tecnología simple con el cultivo del coral Staghorn Acropora cervicornis. Los cráteres de arrecife se distancian en tamaño de aproximadamente 50 a 400m² y fueron dominados ampliamente por fragmentos de bentos aplanado, con una cubierta de coral generalmente por debajo de 2% y el predominio de taxones no constructores de arrecifes (es decir, tapetes de algas filamentosas, macroalgas). La heterogeneidad espacial bentónica fue significativamente menor dentro de cráteres que también resultaron en un reducido valor funcional como tierra de vivero de peces. La riqueza de especies de peces, abundancia y biomasa y densidad coral recluta fueron significativamente menores dentro de cráteres. Tecnología simple, basada en los enfoques de cultivo de comunidad, la cosecha y transplante de A. cervicornis en terrenos anteriormente bombardeados han demostrado un éxito al aumentar el porcentaje de cobertura de coral, la heterogeneidad espacial bentónica y ayudando a rehabilitar funcionalmente la tierra para vivero.

The status of coral reefs and associated fishes and invertebrates of commercial importance in Pedro Bank, Jamaica / Estado de los arrecifes de coral y comunidades de peces e invertebrados con interés comercial asociadas al Banco de Pedro, Jamaica

The coral reefs located off the north coast of the Jamaican mainland are some of the best and most studied reefs in the world. Coral reefs of Pedro Bank, Jamaica were assessed in March, 2012 as part of the KSLOF Global Reef Expedition using a modified Atlantic and Gulf Rapid Reef Assessment (AGRRA) protocol. The main objectives were to: 1) characterize the distribution, structure and health of coral reefs; and 2) evaluate the population status of commercially important reef fishes and invertebrates. This work was conducted to assist in characterizing coral reef habitats within and outside a proposed fishery reserve, and identify other possible conservation zones. Within 20 reefs, live coral cover ranged from 4.9% to 19.2%. Coral communities were dominated by small corals (esp. Agaricia, Porites and Siderastrea) although many sites had high abundances of large colonies of Montastraea annularis and M. faveolata, and these were generally in good condition. A single area, within the proposed fishery reserve, had extensive Acropora cervicornis thickets, and several shallow locations had small, but recovering A. palmata stands. Macroalgal cover at all sites was relatively low, with only three sites having greater than 30% cover; crustose coralline algae (CCA) was high, with eight sites exceeding 20% cover. Fish biomass at all sites near the Cays was low, with a dominance of herbivores (parrotfish and surgeonfish) and a near absence of groupers, snappers and other commercially important species. While parrotfish were the most abundant fish, these were all extremely small (mean size= 12cm; <4% over 29cm), and they were dominated by red band parrotfish (Sparisoma aurofrenatum) followed by striped parrotfish (Scarus iseri). While coral communities remain in better condition than most coastal reefs in Jamaica, intense fishing pressure using fish traps (main target species: surgeonfish) and hookah/spear fishing (main target: parrotfish) is of grave concern to the future persistence of these reefs. The proposed fishery reserve encompasses some of the best coral reef habitat near the Cays, but this MPA should be expanded to encompass other habitats and MPAs should be considered for bank reefs at the northwestern end, as well as Banner Reef and Blowers Rock.

Los arrecifes de coral ubicados en la costa norte de Jamaica son los mejores y mas estudiados corales del mundo. Los corales de arrecife del Banco de Pedro, Jamaica, fueron evaluados en marzo 2012 como parte de la expedición global KSLOF utilizando una modificación del protocolo de estimación rápida de arrecifes para el Atlántico y el Caribe (AGRRA). Los objetivos principales fueron: 1) caracterizar la distribución, estructura y salud de los arrecifes de coral; y 2) evaluar la condición de las poblaciones de peces arrecifales e invertebrados de interés comercial. Este trabajo fue realizado con el propósito de colaborar en la caracterización de hábitats arrecifales, tanto dentro como fuera de un área sugerida como reserva marina, e identificar otras áreas de conservación. Para los 20 arrecifes, la cobertura de coral vivo varió entre 4.9% y 19.2%. Las comunidades de corales son dominadas por corales pequeños (Agaricia, Porites y Siderastrea), aunque en varias localidades se presentó una mayor abundancia de colonias grandes de M. annularis y M. faveolata, y estos se encontraban por lo general en buenas condiciones. Dentro de la reserva pesquera propuesta, una sola área presentó fragmentos de A. cervicornis, y varias localidades someras presentaron pequeños fragmentos de A. palmata, pero en proceso de recuperación. La cobertura de macroalgas en todas las áreas fue relativamente baja, solo tres lugares presentaron más de un 30%; la cobertura de algas coralinas calcárea (CCA) fue alta, ocho lugares excedieron el 20%. La biomasa de peces fue baja en todos los sitios cercanos a los cayos, y hubo dominancia de herbívoros (pez loro y cirujanos), y en general ausencia de chernas, pargos y otras especies de peces de interés comercial. Aunque los peces loro fueron los más abundantes, estos presentaron tamaños extremadamente pequeños (tamaño promedio = 12cm; <4% por encima de 29cm), y estuvieron dominados por el pez loro de banda roja (Sparisoma aurofrenatum), y por el pez loro de rayas (Scarus iseri). Mientras que las comunidades de coral permanecen en mejor condición que muchos de los arrecifes costeros de Jamaica, existe una intensa presión pesquera usando trampas de pesca (principal objetivo: cirujanos) y de compresores de aire (hookah)/ pesca con arpón (principal objetivo: pez loro) es preocupante, y compromete la persistencia y el futuro de estos arrecifes. La reserva marina (MPA) que se sugiere incluye algunos de los mejores hábitats de arrecife coralino cerca de los cayos, pero es recomendable que se amplíe para incluir otros hábitats y que se consideren áreas marinas protegidas en los bancos de arrecife del extremo noroeste, así como el arrecife Banner y Blowers Rock.

Factors influencing the structure and spatial distribution of fishes in the headwater streams of the Jaú River in the Brazilian Amazon

The aim of this study was to investigate the influence of spatial variation in river channels and habitats on the distribution of fish communities in the headwater streams of the Jaú River System, a blackwater tributary of the Negro River. Collections and measurements were made in 34 headwater streams during the period of November- December, 1998. Fish were captured with fish traps and hand nets along standard reaches of two meanders. Data on benthic habitat structure, stream depth and width were collected along lateral transects in each sample reach. A total of 66 fish species from 24 families were collected and classified into seven trophic guilds: allocthonous insectivore, autochthonous insectivore, general insectivore, piscivore, detritivorous planktivore, detritivorous insectivore and insectivorous piscivore. Variations in the distribution and diversity of bottom substrates were important factors influencing fish community structures in these systems. Also, variation in stream size explained the observed variability in fish communities.

O objetivo desse estudo foi investigar a influência da variação espacial de características físicas do canal dos igarapés e habitats na distribuição das comunidades de peixes em igarapés de cabeceira no sistema do rio Jaú. O rio Jaú é um tributário de águas pretas do rio Negro. Coletas e medidas foram realizadas em 34 igarapés de cabeceira durante os períodos de novembro a dezembro de 1998. Os peixes foram capturados com armadilhas e puçás ao longo de dois meandros em cada local. Um total de 66 espécies de peixes de 24 famílias foram coletados e classificados em sete guildas tróficas: insetívoro alóctone, insetívoro autóctone, insetívoro em geral, piscívoro, detritívoro algívoro, detritívoro insetívoro e insetívoro piscívoro. Variações na distribuição e diversidade do substrato de fundo foram importantes fatores influenciando a estrutura da comunidade nesses sistemas. Sendo assim, variações no tamanho dos igarapés mostraram reflexos nas comunidades de peixes.

Factors influencing the structure and spatial distribution of fishes in the headwater streams of the Jaú River in the Brazilian Amazon / Fatores influenciando a estrutura e distribuição espacial dos peixes nos Igarapés de cabeceira do Parque Nacional do Jaú, Amazônia Central

The aim of this study was to investigate the influence of spatial variation in river channels and habitats on the distribution of fish communities in the headwater streams of the Jaú River System, a blackwater tributary of the Negro River. Collections and measurements were made in 34 headwater streams during the period of November- December, 1998. Fish were captured with fish traps and hand nets along standard reaches of two meanders. Data on benthic habitat structure, stream depth and width were collected along lateral transects in each sample reach. A total of 66 fish species from 24 families were collected and classified into seven trophic guilds: allocthonous insectivore, autochthonous insectivore, general insectivore, piscivore, detritivorous planktivore, detritivorous insectivore and insectivorous piscivore. Variations in the distribution and diversity of bottom substrates were important factors influencing fish community structures in these systems. Also, variation in stream size explained the observed variability in fish communities.

O objetivo desse estudo foi investigar a influência da variação espacial de características físicas do canal dos igarapés e habitats na distribuição das comunidades de peixes em igarapés de cabeceira no sistema do rio Jaú. O rio Jaú é um tributário de águas pretas do rio Negro. Coletas e medidas foram realizadas em 34 igarapés de cabeceira durante os períodos de novembro a dezembro de 1998. Os peixes foram capturados com armadilhas e puçás ao longo de dois meandros em cada local. Um total de 66 espécies de peixes de 24 famílias foram coletados e classificados em sete guildas tróficas: insetívoro alóctone, insetívoro autóctone, insetívoro em geral, piscívoro, detritívoro algívoro, detritívoro insetívoro e insetívoro piscívoro. Variações na distribuição e diversidade do substrato de fundo foram importantes fatores influenciando a estrutura da comunidade nesses sistemas. Sendo assim, variações no tamanho dos igarapés mostraram reflexos nas comunidades de peixes.

Fish communities and trophic metrics as measures of ecological degradation: a case study in the tributaries of the river Ganga basin, India / Métricas tróficas y de comunidades de peces como medidas de la degradación ecológica: un estudio de caso en los afluentes de la cuenca del río Ganga, India

In India, freshwater aquatic resources are suffering from increasing human population, urbanization and shortage of all kind of natural resources like water. To mitigate this, all the major rivers have been planned for a river-interlinking through an interlinking canal system under a huge scheme; yet, the baseline information on ecological conditions of those tropical rivers and their fish communities is lacking at present. In view of that, the present study was undertaken to assess the ecological condition by comparing the trophic metrics of the fish community, conservation status and water chemistry of the two tropical rivers of the Ganga basin, from October 2007 to November 2009. The analysis of trophic niches of the available fish species indicated dominancy of carnivorous (19 species) in river Ken and omnivorous (23 species) in Betwa. The trophic level score of carnivorous species was recorded similar (33.33%) in both rivers, whereas omnivorous species were mostly found in Betwa (36.51%) than Ken (28.07%). Relatively undisturbed sites of Betwa (B1, B2 and B3) and Ken (K2, K3 and K5) were characterized by diverse fish fauna and high richness of threatened species. The higher mean trophic level scores were recorded at B4 of Betwa and K4 of Ken. The Bray-Curtis index for trophic level identified the carnivorous species (>0.32) as an indicator species for pollution. Anthropogenic exposure, reflected in water quality as well as in fish community structure, was found higher especially in the lower stretches of both rivers. Our results suggest the importance of trophic metrics on fish community, for ecological conditions evaluation, which enables predictions on the effect of future morphodynamic changes (in the post-interlinking phases), and provide a framework and reference condition to support restoration efforts of relatively altered fish habitats in tropical rivers of India.

En la India, los recursos acuáticos de agua dulce están sufriendo debido a la creciente población humana, la urbanización y la escasez de todo tipo de recursos naturales como el agua. Para mitigar esto, se ha planificado bajo un amplio esquema que todos los grandes ríos estén interconectados a través de un sistema de canales, sin embargo, la información básica sobre las condiciones ecológicas de los ríos tropicales y sus comunidades de peces es escasa en la actualidad. En vista de ello, el presente estudio se realizó para evaluar el estado ecológico, mediante la comparación de los parámetros tróficos de la comunidad de peces, estado de conservación y el agua de los dos ríos tropicales de la cuenca del Ganges, de octubre 2007 a noviembre 2009. El análisis de los nichos tróficos de las especies de peces disponibles indican dominancia de carnívoros (19 especies) en el río Ken y omnívoros (23 especies) en Betwa. El nivel trófico de las especies carnívoras fue similar en ambos ríos (33.33%), mientras que las especies omnívoras fueron mayores en Betwa (36.51%) que en Ken (28.07%). Sitios relativamente inalterados de Betwa (B1, B2 y B3) y Ken (K2, K3 y K5) se caracterizaron por la alta diversidad y riqueza de especies de peces amenazadas. Los puntajes medios más altos del nivel trófico se registraron en B4 de Betwa y K4 de Ken. El índice de Bray-Curtis para el nivel trófico identificó las especies carnívoras (>0.32) como indicadoras de contaminación. Exposición antropogénica, reflejada en la calidad del agua, así como en la estructura de la comunidad de peces, fue más alta, especialmente en los tramos inferiores de ambos ríos. Nuestros resultados sugieren la importancia de métricas tróficas en la comunidad de peces, para la evaluación de las condiciones ecológicas, lo que permite hacer predicciones sobre el efecto de futuros cambios morfodinámicos (en las fases de post-interconexión), y proporcionar un marco y condición de referencia para apoyar los esfuerzos de restauración de hábitat de peces relativamente alterados en los ríos tropicales de la India.

Distribución y abundancia de la comunidad de peces en la porción litoral de la Reserva de la Biósfera Los Petenes, Campeche, México / Distribution and abundance of fish community in the littoral area of "Los Petenes" Biosphere Reserve, Campeche, Mexico

“Los Petenes” Biosphere Reserve (RBLP) is a critical habitat for many aquatic and terrestrial species. It has the biggest and better conserved seagrass beds, and it represents an important habitat for food, protection and breeding of aquatic organisms, and a temporal refuge for migratory species. The objective of this study was to describe the ichthyofauna diversity in the littoral coastal area of the RBLP, to identify the ecological dominant species, and to analyze the abundance of the fish community and its temporal and spatial changes, and their relationship with some environmental variables. Monthly fish samples were obtained with the aid of trawl nets, from 24 samplings sites distributed along the reserve, between May 2009 and April 2010. The trawl net was operated 288 times and 21 795 individuals with 279.5kg of weight were collected. A total of 46 fish species grouped in 34 genera and 23 families were identified. In a spatial scale, the abundance showed the next ranges: 0.018-0.094ind./m²; 0.249-1.072 g/m² and 9.75-19.32g/ind.; the diversity indexes obtained were: Hn=1.46-2.15, J=0.45-0.71 and D=2.08-3.92. In a temporal scale, the abundance and diversity ranged between: 0.026-0.066ind./m2; 0.342-0.764g/m² and 6.49-22.98g/ind.; Hn=1.76-2.08; J’=0.52-0.64 and D=3.07-4.18. Eleven dominant species were identified with a representation of the 94.39% in number of individuals, and 89.66% in weight of the total catch. From the total, eight species had economic or commercial importance, especially Lagodon rhomboides and Haemulon plumierii. The cluster analyses identified four fish associations; these results are discussed in order to identify relationships between habitat-species. Finally, the canonical correspondence analysis evidenced an association between H. plumierii with salinity and dissolved solids. The RBLP has high habitat diversity and its fish community has developed strategies to use all the spatial and temporal conditions and to satisfy the needs of their life cycles.

La Reserva de la Biósfera Los Petenes constituye un hábitat crítico para una gran diversidad de especies de peces, la zona de pastos marinos es utilizada con fines de alimentación, protección, crianza y refugio temporal. El objetivo es analizar la estructura espacio-temporal de la comunidad de peces y su relación con la variabilidad ambiental e identificar las especies dominantes. Se realizaron 12 muestreos mensuales en 24 sitios a partir de mayo 2009 hasta abril 2010. Se realizaron 288 arrastres, se capturó un total de 21 795 organismos con un peso total de 279.5 kg. Se identificaron 46 especies de peces (34 géneros y 23 familias). Los intervalos de variación espacial de la abundancia fueron: 0.018-0.094ind./m²; 0.249-1.072g/m² y 9.75-19.32g/ind. Los índices de diversidad fueron: Hn=1.46-2.15bits/ind., J=0.45-0.71 y D=2.08-3.92. La variación temporal de la abundancia y diversidad fue de 0.026-0.066ind./m²; 0.342-0.764g/m² y 6.49-22.98g/ind. Hn=1.76-2.08; J=0.52-0.64 y D=3.07-4.18. Se identificaron 11 especies dominantes, que representan el 94.39% en número de individuos y 89.66% en peso de la captura total. El análisis cluster permite identificar cuatro grupos de especies que se asocian a las distintas condiciones de hábitat de la reserva. El análisis de correspondencia canónica destaca la asociación de H. plumierii con la salinidad y los sólidos disueltos. La RBLP cuenta con una alta diversidad de hábitats y la comunidad de peces ha desarrollado estrategias para aprovechar todas las condiciones espaciales y temporales y así satisfacer sus necesidades en el desarrollo de sus ciclos de vida.

Validación de dos índices biológicos de integridad (IBI) en la subcuenca del río Angulo en el centro de México / Validation of two indices of biological integrity (IBI) for the Angulo River subbasin in Central Mexico

Efforts to halt freshwater ecosystem degradation in central Mexico can benefit from using bio-monitoring tools that reflect the condition of their biotic integrity. We analyzed the applicability of two fish-based indices of biotic integrity using data from lotic and lentic systems in the Angulo River subbasin (Lerma-Chapala basin). Both independent data from our own collections during two consecutive years, and existing information detailing the ecological attributes of each species, were used to calculate indices of biological integrity for 16 sites in lotic and lentic habitats. We assessed environmental quality by combining independent evaluations water and habitat quality for each site. We found sites with poor, regular and good biotic integrity. Our study did not find sites with good environmental quality. Fish-based IBI scores were strongly and significantly correlated with scores from independent environmental assessment techniques. IBI scores were adequate at representing environmental conditions in most study sites. These results expand the area where a lotic system fish-based IBI can be used, and constitute an initial validation of a lentic system fish-based IBI. Our results suggest that these bio-monitoring tools can be used in future conservation efforts in freshwater ecosystems in the Middle Lerma Basin.

Las acciones para detener el deterioro de los ecosistemas dulceacuícolas del centro del México requieren herramientas de biomonitoreo que permitan el análisis de su integridad biológica. En este trabajo se analizó la viabilidad del uso de dos índices biológicos de integridad (IBI) con base en las comunidades de peces en ambientes lóticos y lénticos en la subcuenca del Río Angulo (Cuenca del Lerma-Chapala). Utilizando datos provenientes de recolectas independientes durante dos años consecutivos e información sobre los atributos ecológicos para cada una de las especies, se calcularon los valores de dos IBI en 16 sistemas lénticos y lóticos. Se estimó también la calidad ambiental a través de la evaluación de la calidad del agua y del hábitat en cada sitio. Se encontró integridad biótica pobre, regular y buena. El estudio no mostró sitios con buena calidad ambiental. Los valores de los IBI presentaron correlaciones altas y significativas con aquellos derivados de metodologías independientes de evaluación ambiental. Los IBI reflejaron de forma fehaciente las condiciones ambientales en la mayoría de los sitios de estudio. Con este análisis se logró la expansión de área de uso del IBI para ambientes lóticos y una validación inicial del IBI para ambientes lénticos. Estos resultados sugieren que las herramientas pueden ser utilizadas en futuros esfuerzos de conservación en cuerpos dulceacuícolas en la cuenca del Medio Lerma.

Fouling communities on ship wreck site in the Gulf of Mannar, India.

The Gulf of Mannar is one of the world’s richest marine biospheres and occupies an area of 10,500 sq.km. Twenty one coral reef islands and small patchy reefs are present between Lat. 800 47’N and Long. 780 12’ E to Lat. 900 15’ N and Long. 790 14’ E. from Pamban to Thoothukudi as an arc. These islands possess a very interesting heterogeneous group of fauna and flora. The study was conducted on a twenty year old ship wreck in the Gulf of Mannar, India. During low tides, remnants of the ship are exposed to about 1.5 meters above the water surface. The entire ship wreck is regarded as an artificial reef that harbors corals, fishes and other fauna. Artificial reefs are beneficial in reef conservation and rehabilitation efforts. Successions of artificial reef communities were preliminarily studied using the Line and Belt transect method to assess the composition of benthic organisms like soft corals (25.6 %) and live corals (23.1 %). The abundance of several common reef fishes is also reported.

Estructura temporal y espacial de la comunidad de peces arrecifales de la Isla San José, Golfo de California, México / Seasonal and spatial structure of reef fish community in San Jose Island, Gulf of California, México

Seasonal and spatial structure of reef fish community in San Jose Island, Gulf of California, México. The Gulf of California is one of the most fish diverse areas of the Tropical Eastern Pacific Ocean. In spite of its economic value, few works have considered fish community studies for optimum management. With the aim to determine the seasonal and spatial variation of fish communities in eight locations around the San Jose Island, some ecological research was conducted from March 2001 to February 2002. For this, visual censuses were used in 48 transects of 100x5m (500m²); specific analysis such as diversity values, the relative abundance and the biological value indexes were undertaken, and a principal component analysis applied. Our results clearly showed two climatic seasons of cold and warm waters. A total number of 26 608 organisms of 112 species and 76 genera of fishes were identified. We used the relative abundance index to determine the most important species, which were: Abudefduf troschelii, Thalassoma lucasanum, Stegastes rectifraenum, Mulloidichthys dentatus, Chromis atrilobata, Lutjanus argentiventris and Scarus ghobban. February was the month with the lowest diversity with a value of 3.12bits/ind. and October was the most diverse (4.13bits/ind.). According to the biological value index (BVI) and considering the climatic seasons, the fish species with the highest score during cold months were: A. troschelii, M. dentatus, S. ghobban, S. rectifraenum and T. lucasanum. Besides, for warmer months, the same fish species were observed but in different order and abundance: A. troschelii, S. ghobban, S. rectifraenum, T. lucasanum and M. dentatus. Using the biological value index, 13 species were those which had a higher overall score. The locations by the Eastern side of the island had a greater number of species and abundance of fish. The principal component analysis (PCA) applied using the seasonal data, species richness, diversity, equity, number of species and total abundance during the warmer months also a PCA within spatial data, showed that location in Punta Colorada had a high correlation with the number of species, diversity and total abundance. Rev. Biol. Trop. 60 (2): 649-667. Epub 2012 June 01.

Para determinar la variación estacional y espacial de la comunidad de peces en ocho localidades alrededor de la Isla San José en el Golfo de California se realizo un estudio ecológico de marzo 2001 a febrero 2002. Además, se utilizaron censos visuales en 48 transectos de 100x5m (500m²). También, se detectaron dos temporadas climáticas: una fría y otra cálida, se observaron 26 608 organismos de 112 especies de 76 géneros de peces. Asimismo, se utilizo el índice de abundancia relativa para determinar las especies más importantes. Febrero fue el mes de menor diversidad y octubre el mayor. De acuerdo con el índice de valor biológico, 13 especies fueron las que obtuvieron un mayor puntaje. En los meses cálidos se presentaron las mismas especies pero en diferente orden y abundancia. Las localidades de la zona oriental de la isla, presentaron un mayor número de especies y abundancia de peces. En el análisis de componentes principales (ACP) la riqueza específica, diversidad, equidad, número de especies y abundancia total se relacionaron con los meses cálidos. Al utilizar el ACP en su forma espacial registro que la localidad Punta Colorada obtuvo una mayor correlación con el número de especies, diversidad y abundancia total.

Changes in the fish community of the Kpong Headpond, lower Volta River, Ghana after 25 years of impoundment

The Kpong Headpond was the second created on the Volta River after Akosombo Dam, primarily as a source of hydroelectric power generation and potable water supply, and additionally, it has supported some fish production in Ghana since impoundment. The changes in fish community of the Kpong Headpond were studied to provide baseline information for strategies formulation to support the socio-economic development of the reservoir. The study identified changes in the fish community of the reservoir by comparing occurrence, composition, relative abundance and relative importance estimates of fish species, families and trophic groups, from available previous studies in the reservoir. From the collated information all fishes identified in the reservoir were categorised based on occurrence and importance as disappeared, appeared, permanent, declined or important, to show current status. The results indicated that the fish community has experienced a shift in the composition and relative abundance of important species, families and trophic groups in terms of number and weight, while remaining ecologically balanced. Representatives of the families Osteoglossidae, Centropomidae and Characidae have declined while representatives of the families Claroteidae, Cyprinidae and Cichlidae have increased. The aufwuch-detritus and herbivores declined while semi-pelagic omnivores increased resulting in a shift in dominance to benthic and semi pelagic omnivores. The appearance of five species and the disappearance of 25 others indicated a dynamic restructuring of the fish community in the reservoir, as expected. Enforcement of fishing regulations including the use of appropriate gear and fishing methods, fishery access control, promotion of culture-based fisheries and improvement in fisher education are recommended topics for sustainable fisheries in the reservoir. Rev. Biol. Trop. 59 (4): 1685-1696. Epub 2011 December 01.

La laguna Kpong se convirtió en la segunda represa creada en el río Volta, después de Akosombo, principalmente para la generación de energía hidroeléctrica y suministro de agua potable, además, contribuye con la producción pesquera de Ghana desde que se formó la misma. Los cambios en la comunidad de peces de la laguna Kpong fueron estudiados con el fin de proporcionar información de referencia para la formulación de estrategias que contribuyan con el desarrollo socio-económico de la represa. El estudio identificó los cambios en la comunidad de peces de la represa mediante la comparación de la ocurrencia, composición, abundancia relativa y estimaciones de importancia relativa de las especies de peces, familias y grupos tróficos. De manera que con base en estudios previos disponibles efectuados en la represa y cotejando tal información con el estado actual de los peces identificados en este sitio, éstos se clasificaron según su presencia e importancia de la siguiente manera: desaparecido, aparecido, permanente, en disminución o importante. Los resultados indicaron que la comunidad de peces ha experimentado un cambio en la composición y abundancia relativa de especies importantes, familias y grupos tróficos en términos de número y peso, aunque continúan permaneciendo ecológicamente balanceados. Representantes de las familias Osteoglossidae, Centropomidae y Characidae han disminuido mientras que los representantes de las familias: Claroteidae, Cyprinidae y Cichlidae han incrementado. Los perifiton-detritívoros y herbívoros disminuyeron, mientras que los omnívoros semipelágicos aumentaron, lo que resulta en un cambio en la dominancia de los bentónicos y los omnívoros semi-pelágicos. La aparición de cinco especies y la desaparición de otras 25, indica una reestructuración dinámica de la comunidad de peces en la represa, como se esperaba. Para una pesca sostenible en la represa se recomienda la aplicación de reglamentos pesqueros, que incluyan el uso de equipo y métodos de pesca apropiados, control de la pesca, promoción de una cultura basada en la pesca y el mejoramiento de la educación de los pescadores.

Effect of environmental quality and mesohabitat structure on a Biotic Integrity Index based on fish assemblages of cerrado streams from Rio Cuiabá basin, Brazil / Efeito da qualidade ambiental e da estrutura do meso-habitat sobre um índice de integridade biótica baseado em assembleias de peixes de córregos de cerrado da bacia do rio Cuiabá, Brasil

Over the last 30 years, the Cerrado has been experiencing various antropic impacts that have brought about alterations to species composition, structure and functioning of aquatic habitats. Therefore, studies on negative impacts are useful to prevent future damage and restore environmental quality. The objectives of our study were: i) to adapt an index of biotic integrity of streams in the Rio Cuiabá Basin and ii) to analyze if the Index of Biotic Integrity (IBI) correlated with the environmental quality measured by the Index of Environmental Quality (IEQ) and with the mesohabitat structure. We sampled 26 streams in sub-basins of the Cuiabá River. In each stream, we closed a stretch of 50 m with blockage nets and used electrofishing to capture fish. To obtain a measure of environmental quality in sampled units, we characterized the stream and its micro basin. For the analyses, we used the Spearman Correlation, Kruskal-Wallis test and Analysis of Multiple Regression. We collected 697 individuals distributed into 6 orders, 15 families and 49 species. The IBI followed changes on environmental quality measured by IEQ when we removed streams that present natural barriers from the analysis (r² = 0.4; r² = 0.58). Types of land use did not affect the biotic integrity (n = 26; df = 4; H = 4,860; p = 0.302), but natural and artificial barriers affected it (n = 26; df = 4; H = 11,027; p = 0.026). The IBI was not sensitive to variations in mesohabitat structure (F2,23 = 0.373; r² = 0.031; Axe 1 p = 0.620; Axe 2 p = 0.490). The IBI is certainly a reasonable instrument for evaluating changes in the environment, but we cannot ignore the fact that we were able to obtain the same result with any combinations of metrics. This makes its analysis and interpretation difficult.

Nos últimos 30 anos, o cerrado tem sofrido severos impactos antrópicos que provocam alterações na composição de espécies, na estrutura e no funcionamento de habitats aquáticos. Dessa forma, estudos sobre impactos negativos são úteis para prevenir futuras degradações e restaurar a qualidade ambiental. Os objetivos do nosso estudo foram: i) adaptar um índice de integridade biótica para os riachos da bacia do rio Cuiabá e ii) analisar se o índice de integridade biótica (IIB) é correlacionado com a qualidade ambiental medida pelo índice de qualidade ambiental (IQA) e com a estrutura do meso-habitat. Amostramos 26 riachos da sub-bacia do rio Cuiabá; em cada um deles, delimitados um segmento de 50 m, utilizando a pesca elétrica como método de coleta. Para obter a medida de qualidade ambiental nas unidades amostradas, caracterizamos os riachos e sua microbacia. Para as análises nós usamos a correlação de Sperman, o teste Kruskal-Wallis e a análise de componentes principais. Coletamos 697 indivíduos distribuídos em 6 ordens, 15 famílias e 49 espécies. O IIB seguiu mudanças na qualidade ambiental medida pelo IQA quando nós removemos da análise os riachos que apresentavam barreiras ambientais (r² = 0.4; r²S= 0.58). Tipos de usos da terra não afetaram a integridade biótica (n = 26; df = 4; H = 4,860; p = 0.302), de modo oposto existiu uma associação negativa entre a presença de barreira e o IIB (n = 26; df = 4; H = 11,027; p = 0.026). O IIB não foi sensível às variações na estrutura do meso-habitat (F2,23 = 0.373; r² = 0.031; Axe 1 p = 0.620; Axe 2 p = 0.490). O IIB mostrou-se como um razoável instrumento para avaliar as mudanças do ambiente, mas não podemos ignorar que com várias combinações das métricas podemos obter um mesmo resultado, o que dificulta sua análise e interpretação.

Relación entre comunidad íctica y cobertura vegetal riparia en períodos hidrológicos (Eje Cafetero, Colombia) / Relação da comunidade de peixes e o tipo de cobertura da vegetação ripária em dois períodos hidrológicos (Eixo Cafeteiro da Colômbia) / Relationship between fish community and riparian vegetation cover in hydrological periods (Coffee-Growing Region, Colombia)

Objetivo. Evaluar la relación entre estructura y dieta de la comunidad íctica y la cobertura vegetal riparia (CVR) en dos períodos hidrológicos (PEHI) en riachos de la cuenca del río La Vieja. Materiales y métodos. Las colectas fueron realizadas con electropesca y rapiché en marzo y mayo de 2010. La eficiencia del esfuerzo muestral fue evaluada con el estimador Chao2. La estructura fue analizada mediante los índices: riqueza, dominancia, diversidad y equidad, siendo comparados a través de un ANOVA. Los contenidos gastrointestinales se analizaron usando los índices: coeficiente de vacuidad, frecuencia de ocurrencia, volumétrico e importancia alimentaria. Para analizar la relación entre dieta, PEHI y CVR se utilizó el coeficiente de correlación múltiple (r), el coeficiente de determinación (r2) y un Análisis de Correspondencias Canónicas (ACC). Resultados. Según el estimador Chao2, en la mayoría de los riachos los valores de riqueza íctica en estos ambientes son representativos. No existen diferencias significativas (P>0,05) entre las variables estructurales, el PEHI y las CVR. Según el r y el r2, la dieta de la mayoría de las especies no varió en función de la CVR y el PEHI. Sin embargo, según el ACC la dieta varió en función del PEHI, pero no en función de la CVR. Conclusiones. La estructura de la comunidad íctica no presentó cambios según la CVR o el PEHI. Aunque la mayoría de especies no cambiaron de dieta, la comunidad sí presenta cambios en esta en función del PEHI, debido al cambio en la composición; no obstante, los cambios de dieta no se detectaron por tipo de CV...

Relationship between fish community and riparian vegetation cover in two hydrological periods (Coffee-growing region, Colombia) Objective. To assess the relationship between structure and diet of the fish community and the riparian vegetation cover (RVC), in two hydrological periods (HYPE) in streams of the La Vieja river basin. Materials and methods. Collections were done with electrofishing and rapiché in March and May 2010. Efficiency of sampling effort was assessed with the estimator Chao2. Structure was analyzed using the indices of richness, dominance, diversity and evenness which were compared with an ANOVA. Gastrointestinal contents were analysed with the indices of vacuity coefficient, frequency, volume and food importance. We examined the relationship among diet, HYPE and RVC using the multiple correlation coefficient (r), the coefficient of determination (r2) and a Canonical Correspondence Analysis (CCA). Results. According to the Chao2 estimator, in most streams the fish species richness values are representative. There were no significant differences (P>0.05) among the structural variables, the HYPE and the RVC. According to r and r2 the diet of most fish species did not vary as a function of RVC and HYPE; however, according to the CCA diet varies as a function of HYPE but not of RVC. Conclusions. The fish community structure did not show changes according to RVC and HYPE. Although most species showed no changes in their diet, the community did show changes in diet according to HYPE, due to a change in composition; however diet changes were not detected by RVC...

Relação da comunidade de peixes e o tipo de cobertura da vegetação ripária em dois períodos hidrológicos (Eixo Cafeteiro” da Colômbia). Objetivo. Avaliar a relação entre estrutura e dieta da comunidade de peixes e a cobertura da vegetação ripária (CVR) em dois períodos hidrológicos (PEHI), em córregos da bacia do Rio “La Vieja”. Materiais e métodos. As coletas foram realizadas com pesca elétrica e rapiché em março e maio de 2010. A eficiência do esforço amostral foi avaliada com o estimador Chao2. A estrutura foi analisada através dos índices de riqueza, diversidade, dominância e equidade, e comparados pelo teste ANOVA. A dieta foi analisada pelos conteúdos gastrointestinales, utilizando-se os índices: coeficiente de vacuidade, freqüência de ocorrência, volume e importância alimentar. Para examinar a relação entre dieta, PEHI e CVR foram utilizados o coeficiente de correlação múltipla (r), o coeficiente de determinação (r2) e Análise de Correspondência Canônica (ACC). Resultados. De acordo com o estimador Chao2 na maioria dos córregos os valores da riqueza de peixes nestes ambientes foram representativos. Não existem diferencias significativas (P>0,05) entre as variáveis estruturais, tipo de CVR e PEHI. Segundo o r e o r2, a dieta da maioria das espécies variou em função da CVR e PEHI. Embora.Analizando a dieta da comunidade e segundo o ACC, a dieta variou em função do PEHI mas não em função da CVR. Conclusões. A estrutura da comunidade de peixes não apresentou mudanças segundo a CVR ou PEHI. Apesar que a maioria de espécies não apresentaram mudanças em sua dieta, a comunidade sim apresenta mudanças em esta em função do PEHI, devido á mudança na composição; embora, as mudanças na dieta não foram detectadas segundo o CVR...

Influence of Palythoa caribaeorum (Anthozoa, Cnidaria) zonation on site-attached reef fishes

This work aimed to test the influence of Palythoa caribeorum, a widely distributed zoanthid in the Atlantic, on site-attached reef fish in a subtropical rocky shore. Density, richness and vertical distribution of reef fish inside (ID) and outside (OD) previously chosen P. caribaeorum dominance patches were compared through stationary visual censuses along three different periods. Fishes were grouped in different trophic guilds to evidence differences in resources uses in both treatments. A complexity index was estimated by the chain link method and percentage covering of benthic organisms was obtained analyzing random points from replicated photo-quadrats. We observed thirty-eight species of fishes, belonging to twenty-five families. Reef fish communities between studied patches were similar,both in terms of species composition and vertical distribution. Considering only the most site-attached fishes, which were the most frequent and abundant species, data showed that ID sustains higher diversity and abundance than OD. Results showed that benthic composition differ significantly among patches whereas complexity remained without differences. Otherwise, results indicated that these areas might play an important role in space limitation, structuring neighboring benthic community and consequently reef fish assemblages.

Este estudo visou testar a influência de Palythoa caribeorum, um zoantídeo amplamente distribuído no Atlântico, na estruturação da comunidade de peixes recifais associados a um costão rochoso de uma região subtropical. A densidade, a riqueza e a distribuição vertical de peixes recifais em áreas previamente selecionadas com e sem a dominância de Palythoa caribaeorum foram comparadas através de censos visuais estacionários em três períodos distintos de tempo. Os peixes foram agrupados em guildas tróficas a fim de evidenciar diferenças nos usos dos recursos nas diferentes áreas analisadas. Foram analisados também índices de complexidade estrutural através do método da corrente e os percentuais de cobertura bentônica através de fotos quadracts replicados. Foram registradas trinta e oito espécies de peixes recifais de vinte e cinco famílias diferentes. Acomunidade de peixes entre as áreas estudadas foi similar tanto em composição de espécies quanto em distribuição vertical. Considerando apenas as espécies mais associadas ao substrato, que foram as mais freqüentes e abundantes, os dados mostraram que as áreas com dominância de P. caribaeorum sustentam maior diversidade e abundância do que as áreas sem a dominância de P. caribaeorum. Foram encontradas ainda diferenças significativas na composição bentônica entre os diferentes tratamentos estudados, mas não foram verificadas diferenças entre a complexidade estrutural entre estas áreas. No entanto, os resultados sugerem que as áreas com dominância de P. caribaeorum podem desempenhar papel importante na limitação de espaços, estruturando as comunidades bentônicas e, conseqüentemente, afetando a comunidade de peixes recifais.

The fish fauna of Brokopondo Reservoir, Suriname, during 40 years of impoundment

We investigated long-term changes in the fish fauna of Brokopondo Reservoir, Suriname, the first large reservoir (1560 km²) that was created in tropical rainforest. Before closure of the dam in 1964, the fish fauna of Suriname River had 172 species, high diversity and high evenness. The riverine fauna was dominated by small-sized species, but no single species was dominant in numbers. Large catfishes were dominant in biomass. Species were evenly distributed over riverine habitats: rapids, tributaries and main channel. Four years after closure of the dam, only 62 fish species were collected from Brokopondo Reservoir, but the composition of the fish fauna was still changing. The reservoir fauna in 1978 was very similar to the reservoir fauna in 2005, indicating that a stable equilibrium had been reached 14 years after closure of the dam. The reservoir fauna had 41 species, low diversity and low evenness. Most species of Suriname River and its tributaries with strict habitat requirements did not survive in Brokopondo Reservoir. Fish community structure was different among four habitats of Brokopondo Reservoir. The open-water habitat (10 species) was dominated by the piscivores Serrasalmus rhombeus, Acestrorhynchus microlepis and Cichla ocellaris and their prey Bryconops melanurus and two Hemiodus species. B. melanurus fed on zooplankton, Culicinae pupae and terrestrial invertebrates. Hemiodus fed on fine flocculent detritus, demonstrating that the detritus-based food chain was still important in late stages of reservoir development. Serrasalmus rhombeus also fed on peccaries that drowned when swimming across the large reservoir in rough weather. The shore community (27 species) was dominated by seven cichlids, but early stages and juveniles of the open-water species S. rhombeus and B. melanurus also occurred in the shore habitat. Fish biomass in the shore habitat was 66.5±59.9 kg ha-1. The cichlid Geophagus surinamensis and the characid...

Foram pesquisadas as modificações a longo prazo na ictiofauna do reservatório de Brokopondo, o primeiro de grande porte (1560 km²) construído em floresta tropical úmida. Antes do fechamento da barragem em 1964, a ictiofauna do rio Suriname possuía 172 espécies, com diversidade e equitabilidade altas. A fauna do rio era dominada por espécies de pequeno porte, mas nenhuma delas dominava em número de indivíduos. Em termos de biomassa, os grandes bagres eram dominantes. As espécies estavam homogeneamente distribuídas nos diferentes hábitats: corredeiras, afluentes e canal principal. Quatro anos depois do fechamento da barragem, somente 62 espécies de peixes foram coletadas no reservatório de Brokopondo, mas a composição da ictiofauna ainda estava mudando. Em 1978, a ictiofauna do reservatório era semelhante à de 2005, indicando que um equilíbrio estável foi atingindo 14 anos depois do fechamento da barragem. A ictiofauna do reservatório tinha 41 espécies, diversidade e equitabilitade baixas. A maioria das espécies do rio Suriname que tinham exigências estreitas de hábitat não sobreviveram no reservatório. A estrutura das comunidades de peixes foi diferente nos quatro hábitats do reservatório de Brokopondo. O hábitat das águas abertas (10 espécies) foi dominado pelos piscívoros Serrasalmus rhombeus, Acestrorhynchus microlepis e Cichla ocellaris e suas presas Bryconops melanurus e duas espécies de Hemiodus. Bryconops alimentou se de zooplâncton, pupas de Culicidae e invertebrados terrestres. Hemiodus alimentou se de detritos floculentos, demostrando que a cadeia alimentar baseada em detritos ainda era importante em estßgios avançados de desenvolvimento dos reservatórios. Serrasalmus rhombeus também come queixadas que se afogam quando tentam atravessar nadando o grande reservatório em condições de mau tempo. A comunidade das margens (27 espécies) foi dominada por sete Cichlidae, embora estágios iniciais e juvenis das espécies de águas abertas...