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We provide extensive surveys in eight estuaries along the coast of Ceará State in Northeastern Brazil, including local samples and data compiled from online data bases and literature. Samplings resulted in a checklist of the estuarine fish fauna, which recorded 126 fish species, and provides original information of some estuaries. Most of the sampled marine species are widely distributed and many are important commercial species for the artisanal fisheries. The addition of records from existing inventories and online collections increases the number of species to 245, of which 11 are threatened (critically endangered or vulnerable) and six are introduced. Our study provides an updated list of fish species of the estuaries along the semiarid coast of Brazil and is intended as a subsidy for further research, conservation and management efforts.

The Neotropical region hosts 4225 freshwater fish species, ranking first among the world's most diverse regions for freshwater fishes. Our NEOTROPICAL FRESHWATER FISHES data set is the first to produce a large-scale Neotropical freshwater fish inventory, covering the entire Neotropical region from Mexico and the Caribbean in the north to the southern limits in Argentina, Paraguay, Chile, and Uruguay. We compiled 185,787 distribution records, with unique georeferenced coordinates, for the 4225 species, represented by occurrence and abundance data. The number of species for the most numerous orders are as follows: Characiformes (1289), Siluriformes (1384), Cichliformes (354), Cyprinodontiformes (245), and Gymnotiformes (135). The most recorded species was the characid Astyanax fasciatus (4696 records). We registered 116,802 distribution records for native species, compared to 1802 distribution records for nonnative species. The main aim of the NEOTROPICAL FRESHWATER FISHES data set was to make these occurrence and abundance data accessible for international researchers to develop ecological and macroecological studies, from local to regional scales, with focal fish species, families, or orders. We anticipate that the NEOTROPICAL FRESHWATER FISHES data set will be valuable for studies on a wide range of ecological processes, such as trophic cascades, fishery pressure, the effects of habitat loss and fragmentation, and the impacts of species invasion and climate change. There are no copyright restrictions on the data, and please cite this data paper when using the data in publications.

Hydrological disconnection in intermittent rivers is known to increase β-diversity by limiting the dispersal of species and decreasing environmental similarity between sites. Knowledge of the mechanisms driving variation within and between local communities helps elucidate the role of environmental and spatial processes responsible for community composition at multiple scales in intermittent rivers. In this study, we investigated the spatial and environmental patterns of zooplankton β-diversity in an intermittent river in a semiarid region in Brazil. We hypothesized that (1) the zooplankton metacommunity is determined primarily by turnover, and (2) the structure of the zooplankton metacommunity is more heavily influenced by environmental than spatial factors. Our samples yielded 46 taxa of rotifers and cladocerans. β-taxonomic diversity was high, with a predominance of turnover compared with nestedness. The partitioning analysis showed that environmental and spatial processes had a significant influence on the distribution of zooplankton species, but the former had the greatest explanatory power. In the redundancy analysis, high values of temperature, oxygen and submersed macrophytes were significantly correlated with species variation. The observed β-diversity values closely reflected the turnover pattern, whereas Cladocera and Rotifera diverged between predictive processes. Our results highlight the importance of adopting appropriate conservation measures for intermittent river networks as a whole.

A ecologia de peixes de riachos intermitentes da regiao semiarida brasileira e ainda pouco conhecida, embora nos ultimos vinte anos, o numero de pesquisadores dedicados a esse tema venha aumentando consideravelmente. No entanto, ainda existem expressivas lacunas quando os estudos em riachos intermitentes sao comparados aos que tratam de riachos perenes de outras regioes do Brasil. Questoes que abordem variacoes sazonais esbarram na determinacao de metodos e tecnicas de captura da ictiofauna que sejam eficientes nas diferentes fases do ciclo hidrologico. Alem disso, tecnicas amplamente difundidas em sistemas perenes, como a pesca eletrica, na maioria das vezes, nao tem se mostrado eficazes. Aspectos relacionados a biologia, fisiologia, comportamento, ecologia funcional e taxonomica dos peixes ainda precisam ser investigados levando-se em consideracao as variacoes sazonais e de escala espacial. Diante da crescente transformacao imposta a regiao semiarida brasileira pelo uso extensivo dos recursos naturais e pelas mudancas climaticas, os ambientes aquaticos e sua biodiversidade estao ameacados pela transformacao da vegetacao ciliar, lancamento de residuos, introducao de especies, pela modificacao do seu curso e perenizacao artificial de muitos canais. Assim, neste artigo, apresentamos e discutimos os estudos desenvolvidos sobre a ecologia de peixes nos riachos intermitentes da regiao semiarida brasileira e as lacunas e os desafios a serem enfrentados pelas pesquisas futuras. ECOLOGY OF INTERMITTING STREM FISH: The ecology of fish from intermittent streams in the Brazilian semi-arid region is still little known. In the past twenty years, the number of researchers dedicated to this topic has increased considerably. However, significant gaps still exist when compared to the perennial streams of other regions of Brazil. Questions that address seasonal variations come up against the determination of capture methods and techniques that are efficient in the different phases of the hydrological cycle. In addition, techniques widely used in perennial systems, such as electrofishing, in most cases, have not been effective. Aspects related to biology, physiology, behavior, functional and taxonomic ecology of fish still need to be investigated taking into account seasonal and spatial scale variations. In view of the growing transformation imposed on the Brazilian semi-arid region by the extensive use of natural resources and by climate change, aquatic environments and their biodiversity are threatened by the transformation of riparian vegetation, the sewage release, the species introduction, the modification of its course and artificial perennialization. Thus, we will present and discuss, in this paper, the studies developed on the ecology of fish in the intermittent streams of the Brazilian semi-arid region and the gaps and challenges to be faced by future research.

Fish diversity is generally high in drainage networks in perennial systems. On the other hand, little is known about the importance of drainage networks in semiarid regions. The scant attention given to rivers in semiarid regions so far may in part be explained by the high intermittency and low ramification of these drainage networks and their incorrect classification as systems of low diversity and productivity. In this study, we investigated the importance of the drainage system of an intermittent river system in Brazil with regard to taxonomic and functional β-diversity. To do so, we evaluated the importance of both tributaries (branches) (12 sampling points) and the main stem (7 sampling points).We initially modeled the spatial structure within the branches and the main stem using asymmetric eigenvector maps. We then partitioned β-diversity values between local (biotic and abiotic) and spatial factors (positive spatial autocorrelation). The higher β-diversity values observed for branches were explained mainly by predation and environmental selection. On the other hand, in the main stem, β-diversity was best explained by a combination of environmental conditions and spatial factors. In general, local factors were more important in the functional approach than in the taxonomic approach, supporting their joint use in metacommunity studies. Our results suggest that fish metacommunity structure in branches may be responsible for maintaining regional patterns of β-diversity in semiarid river systems.

The successful adaptation of populations to a wide range of environments is a central topic in the ecology. Based on the assumption that body shape may affect survival, we evaluated to what extent biotic and abiotic factors are capable of inducing morphological changes in Brazilian silverside populations (Atherinella brasiliensis). To reach this goal, we compared 18 morphological traits of specimens from five ecosystems representing three types of environment (estuary, coastal lagoon, reservoir). Populations from estuaries displayed greater anal fin area and greater caudal fin aspect ratio and area. Populations from coastal lagoons had more compressed bodies, larger heads, and slightly broader caudal peduncles. The fish from estuaries and coastal lagoons had longer caudal peduncles, larger pelvic fins and larger eye area. Populations from reservoir had more depressed bodies and greater oral protrusion. Food availability was significantly and explained 31% of the observed ecomorphological patterns. Overall, the morphology of the respective populations was consistent with each type of environment, making it possible to associate phenotypic variation with habitat and feeding patterns, although abiotic factors were more significant than biotic factors. In conclusion, landlocked populations of A. brasiliensis are sustainable and add to current knowledge of phenotypical variability in a species widely distributed along the Western Atlantic coast.

A etnoecologia busca compreender como diferentes grupos humanos se inter-relacionam com os recursos naturais e ecossistemas que manejam e como os compreendem. Os pescadores passam parte considerável de suas vidas em contato com o ambiente e espécies que manejam, portanto, são portadores de relevantes saberes sobre tais. De modo que compreender as interfaces entre os conhecimentos destas populações e o conhecimento científico, possibilita apontar lacunas a serem investigadas e orientar a conservação dos recursos pesqueiros. Desta forma, objetivou-se comparar os conhecimentos etnoictiológicos dos pescadores artesanais dos açudes públicos Araras e Edson Queiroz (bacia do médio rio Acaraú-CE) com a literatura científica. Para isso, foi selecionada uma população representativa para cada um destes açudes: Ilha de Esaú, para o açude Araras, e Vila São Cosme, para o Edson Queiroz. Foram empregadas estratégias de observação participante, entrevistas semiestruturadas, estímulo visual e turnês-guiadas com pescadores locais. As entrevistas abordaram aspectos etnoecológicos das principais espécies de peixes capturadas na região. Concluiu-se que os pescadores possuem maior conhecimento das espécies nativas, por manejarem-nas há mais tempo e/ou por mudança no comportamento das espécies exóticas ante um ecossistema com características marcadamente divergentes dos ecossistemas de origem destas espécies. Estes conhecimentos podem contribuir para futuros estudos científicos e ser incorporados na elaboração de planos de gerenciamento e manejo sustentável dos recursos hídricos e pesqueiros da região média do Acaraú.

Con el fin de caracterizar la ictiofauna y describir algunos aspectos de la actividad pesquera en la microcuenca del rió Chajeradó, se muestrearon dos ciénagas, tres ríos y cuatro quebradas entre noviembre y diciembre de 1995. En total se capturaron veintiocho especies, pertenecientes a cinco órdenes y catorce familias. El 21.4% de las especies se encontraron exclusivamente en corrientes menores, 14.3% en los ríos y 10.7% en las ciénagas. Los 91 indígenas de la comunidad de Chajeradó practican la pesca con anzuelo y flecha en ríos y quebradas. Las veinte personas de la comunidad negra de Tadía pescan con trasmallo en las ciénagas y en las bocas de los grandes ríos. Los indígenas y negros realizan la actividad pesquera dentro del límite territorial de cada comunidad. Las especies más importantes para la comercialización son Prochilodus magdalenae y Hoplias malabaricus. Un 68.5% de los peces comerciales capturados no tenían la talla mínima de madurez sexual.

15 pages, 6 figures, 3 tables, supplementary material https://doi.org/10.1007/s10750-017-3432-8, Fish and invertebrates are introduced in freshwaters around the world for commercial purposes, despite widely known impacts on food webs and biological invasions. As a proxy for artificial environments, we modeled a typical reservoir in a Brazilian semiarid region using an ecosystem approach. We compared the role of native and non-native invasive species (NIS) in the food web, between dry and wet periods, and under the influence of an extreme drought period (from 2011 to 2015), simulating the variation in fish biomasses due to decreasing consumption. Key ecosystem groups were fishes (mainly NIS), birds, and insects. Nutrient cycling was dependent on invaders, while the trophic structure was detritus based during the drought. Biomass of detritivores was almost two times higher than herbivores, and native fish species decreased abruptly in response to invaders and volume variation. The dominance of low-trophic levels (TLII) and tilapia—Oreochromis niloticus (Linnaeus, 1758) and other tilapiines—resulted from interactions among invaders, feeding behavior on benthos, and environmental seasonality, tending toward biotic homogenization (“benthification”) at the ecosystem level. An increasing relevance of detritivores with cascading effects in ecosystems subject to drought, multiple introductions, and ubiquitous food sources has clear implications for the fisheries and the water quality, We are thankful to the Fundação Cearense de Apoio ao Desenvolvimento Científico e Tecnológico (FUNCAP, AE1-0052-00044.01.00/11 SPU nº: 11295057-4) for the funding to this project. Coordenadoria de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) for granting the first author with scholarships and funding M. Coll (PVE A063-2013), and Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) for the funding to JRS Vitule (310850/2012-6 and 303776/2015-3)

Tidepools are considered ecosystems of high interchangeable fish biota. However, natural and anthropogenic actions that alter negatively marine ecosystems functioning (e.g., algal exploitation) are causing homogenization of fish biodiversity. Here, we describe the functional and taxonomic assembling of fishes in beach rocks of northeastern Brazil. Traits of fish species were retrieved from Fishbase and beta diversity was assessed by the dispersion of abundance, presence-absence and functional diversity in the multivariate space. We explained spatial-temporal variation in: alpha diversity, taxonomic and functional community composition; as well as temporal variation in functional, beta and gamma diversities. We found an annual stability in fish diversity and composition, and that fish biota was assembled mainly per tidepools’ depths. Substrate heterogeneity was correlated to depth, highlighting the role of local features as filters to organize the fish fauna vertically in tidepools, especially a cultivation of algae that influences the local assembling. We also highlight the uniqueness status of beach rocks in the Brazilian tropical region.

Among Neotropical freshwater ecoregions, the Mid-Northeastern Caatinga (MNCE) is a fish knowledge gap. Its temporary drainages are receptors of the São Francisco interbasin water transfer project (SFR-IWT) in the Brazilian semiarid. We provide a comprehensive baseline of fish richness of the five SFR-IWT basins. Species richness, shared, endemic, threatened and non-native species were obtained using sampling, ichthyologic collections, literature and online repositories (306 localities). In total 121, species were recorded, 111 of them native, and 16 (14.41%) listed for all basins. Higher richness of native species (78, 70.27%) was recorded in the São Francisco lower-middle stretch (SFRE), including 23 endemic, 61 (54.95%) in MNCE basins (13 endemic), and 28 (25.23%) shared between both ecoregions. In the MNCE, 50 species were recorded in Jaguaribe (JAG), 39 in Piranhas-Açu, 36 in Paraíba do Norte, and 32 in Apodi-Mossoró (APO). The number of species shared between the SFRE and each receptor basin varied from 24 (23.08%, JAG) to 20 (22.22%, APO). JAG contains 81.97% of the receptor basins’ species. Its higher richness and endemism deserve special attention regarding the ongoing hydrological changes. This study will help detect possible modifications in the ichthyofauna of the main MNCE drainages. Resumo Dentre as ecorregiões dulcícolas neotropicais, a Nordeste Médio-Oriental (MNCE) é uma lacuna de conhecimento sobre peixes. Suas drenagens temporárias são receptoras do projeto de transposição do São Francisco (SFR-IWT) no semiárido brasileiro. Fornecemos uma linha de base abrangente da riqueza de peixes das cinco bacias do SFR-IWT. Riqueza de espécies, espécies compartilhadas, endêmicas, ameaçadas e não-nativas foram obtidas através de amostragem, coleções ictiológicas, literatura e repositórios online (306 localidades). No total, foram registradas 121 espécies, 111 nativas e 16 (14,41%) listadas para todas as bacias. A maior riqueza de espécies nativas (78, 70,27%) foi registrada no trecho sub-médio do São Francisco (SFRE), incluindo 23 endêmicas e 61 (54,95%) nas bacias da MNCE (13 endêmicas), e 28 (25,23 %) compartilhadas entre ambas ecorregiões. Na MNCE, foram registradas 50 espécies na Jaguaribe (JAG), 39 na Piranhas-Açu, 36 na Paraíba do Norte e 32 na Apodi-Mossoró (APO). O número de espécies compartilhadas entre SFRE e cada bacia receptora variou de 24 (23,08%, JAG) a 20 (22,22%, APO). JAG contém 81,97% das espécies das bacias receptoras. Sua maior riqueza e endemismo merecem atenção especial em relação às mudanças hidrológicas em curso. Este estudo ajudará a detectar possíveis modificações na ictiofauna das principais drenagens da MNCE.

La laguna Imboassica (estado de Rio de Janeiro), tuvo de 1993 a 2001 cuatro aberturas del cordón de arena que la separa del mar. Durante este perí­­odo fueron realizadas 28 colectas de peces, siendo 55.6% de las especies de valor comercialclasificada en guildas funcionales como: residentes en lagunas costeras (RLC), marina-dependientes (MD), visitantes marinas (VM) y de agua dulce (D). La captura por unidad de esfuerzo (CPUE) de las especies de interés comercial en los perí­­odos antes y después de las aberturas fue obtenida de acuerdo al tiempo y área de exposición de las redes. No hubo variaciones significativas en la abundancia de todas las guildas antes y después de las aberturas del cordón de arena. Fue observada una tendencia de aumento en la abundancia de individuos de las especies VM, RCL y MD en los perí­­odos posteriores a abertura del cordón de arena. Cuando este permaneció cerrado por aproximadamente tres aí­±os, fueron realizadas 21 colectas de peces, con aumento en la abundancia de dulcicolas y disminución de otras guildas (VM, RCL y MD). La producción pesquera de la laguna Imboassica es considerada baja y varia por la abertura y cierre del cordón arenoso.

Environmental and spatial factors are known as the main determinants of community variation in aquatic organisms. However, historical factors may interact with local processes to regulate community structure patterns. Here we compared historical, environmental, and spatial factors in a multi-scale approach in order to identify the main drivers structuring species composition and functional diversity of fish communities in forest enclaves across three hydrographic basins in semiarid Brazil Caatinga biome. We initially modeled spatial structure within each basin using asymmetric eigenvector maps (AEM). We then partitioned the explanation of the variation in local community structure into three groups of predictor variables: (1) environmental variables, (2) spatial variables, and (3) phylogenetic history. Biogeographical bias was assessed using a basin identity matrix as covariable. The combination of 1, 2, and 3 explained the variation in species composition, while pure spatial, phylogenetic, and environmental components explained the distribution of functional groups and their nested patterns. Our findings confirmed the importance of phylogenetic history, as well as the usefulness of robust methods in community studies in refining explanations of the processes determining variation in species composition and functional groups.

Made available in DSpace on 2018-11-30T03:55:49Z (GMT). No. of bitstreams: 0 Previous issue date: 2018-09-19 Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Fundação de Amparo à Pesquisa do Estado de Minas Gerais (FAPEMIG) Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Several hypotheses are used to explain species richness patterns. Some of them (e. g. species- area, species-energy, environment-energy, water-energy, terrestrial primary productivity, environmental spatial heterogeneity, and climatic heterogeneity) are known to explain species richness patterns of terrestrial organisms, especially when they are combined. For aquatic organisms, however, it is unclear if these hypotheses can be useful to explain for these purposes. Therefore, we used a selection model approach to assess the predictive capacity of such hypotheses, and to determine which of them (combined or not) would be the most appropriate to explain the fish species distribution in small Brazilian streams. We perform the Akaike's information criteria for models selections and the eigenvector analysis to control the special autocorrelation. The spatial structure was equal to 0.453, Moran's I, and require 11 spatial filters. All models were significant and had adjustments ranging from 0.370 to 0.416 with strong spatial component (ranging from 0.226 to 0.369) and low adjustments for environmental data (ranging from 0.001 to 0.119) We obtained two groups of hypothesis are able to explain the richness pattern (1) water-energy, temporal productivity-heterogeneity (AIC = 4498.800) and (2) water-energy, temporal productivity-heterogeneity and area (AIC = 4500.400). We conclude that the fish richness patterns in small Brazilian streams are better explained by a combination of Water-Energy + Productivity + Temporal Heterogeneity hypotheses and not by just one. Univ Fed Para UFPA, Lab Ictiol Altamira, Altamira, Para, Brazil Univ Estadual Maringa, Nucleo Pesquisas Limnol Ictiol & Aquicultura Nupe, Maringa, Parana, Brazil Univ Estadual Paulista UNESP, Lab Ictiol, Sao Jose Do Rio Preto, SP, Brazil Univ Paulista, Sorocaba, SP, Brazil Univ Estado Rio De Janeiro, Dept Ecol, Rio De Janeiro, RJ, Brazil Univ Fed Ceara, Dept Biol, Ctr Ciencias, Fortaleza, Ceara, Brazil Univ Fed Ceara, Inst Ciencias Mar LABOMAR, Fortaleza, Ceara, Brazil Univ Fed Rio Grande do Norte UFRN, Dept Bot Ecol & Zool, Ctr Biociencias, Natal, RN, Brazil Univ Fed Lavras UFLA, Dept Biol, Lavras, MG, Brazil UFT, Porto Nacl, Tocantins, Brazil Univ Fed Para UFPA, Inst Ciencias Biol, Belem, Para, Brazil INPA, Coordenacao Biodiversidade, Manaus, Amazonas, Brazil Univ Brasilia, Dept Zool, Brasilia, DF, Brazil Univ Fed Sao Carlos, Sorocaba, SP, Brazil Pontificia Univ Catolica Goias, Programa Mestrado Sociedade Tecnol & Meio Ambient, UNIEvangel, Goias Ctr Biol Aquat, Goiania, Go, Brazil UFES, Dept Ciencias Agr & Biol, Ctr Univ Norte Espirito Santo CEUNES, Sao Mateus, ES, Brazil Univ Estadual Paulista, Inst Biociencias, Botucatu, SP, Brazil Univ Fed Minas Gerais, Dept Genet Ecol & Evolucao, Inst Ciencias Biol, Belo Horizonte, MG, Brazil Univ Fed Goias, Dept Ecol, Inst Ciencias Biol, Campus 2 UFG, Goiania, Go, Brazil Univ Estadual Paulista UNESP, Lab Ictiol, Sao Jose Do Rio Preto, SP, Brazil Univ Estadual Paulista, Inst Biociencias, Botucatu, SP, Brazil CNPq: 457463/2012-0 CNPq: 552009/2011-3 CNPq: 471283/2006-1 CNPq: 304002/2014-3 FAPEMIG: 304002/2014-3

The three-spot gourami, Trichopodus trichopterus (Pallas, 1770), is naturally distributed in Southeast Asia: Indonesia and in the Mekong river basin (Low and Lim, 2012). Under natural conditions is found in slow-flowing streams, shallow lakes and swamps with lush riparian vegetation (Rainboth, 1996), tolerates large pH and temperature fluctuations and low levels of dissolved oxygen due to a suprabranchial labyrinth (Low and Lim, 2012; Blank and Burggren, 2014). The juveniles eat mainly zooplankton and benthonic algae, while adults are opportunistic omnivores (Low and Lim, 2012). Due to its usefulness in the fight against mosquito larvae and its popularity as an ornamental fish, the species has been introduced in many regions worldwide (Webb et al., 2007). The present study constitutes the second report of T. trichopterus from the Mid-Northeastern Caatinga fish ecoregion, and first report of a species of the genus Trichopodus in the state of Ceará (Northeastern Brazil). On 16 November 2015 and 19 November 2015, specimens of T. trichopterus were captured in the Santo Anastácio (SA) reservoir during monitoring of the ecosystem conducted by the Laboratory of Aquatic Ecology (LEA/UFC). Located in the Metropolitan basin, within Federal University of Ceará (UFC), the reservoir is part of the Maranguapinho river basin (Figure 1). Following capture with a sieve among aquatic macrophytes, the

AIM: There is currently no consensus regarding the physical and chemical variability of tropical reservoirs. In semiarid Northeastern Brazil, reservoirs are among other things used for human consumption, industrial water supply and intensive fish farming, all of which can impact water quality. The objective of this study was to evaluate the physical and chemical variability of the water in Sítios Novos, a reservoir in semiarid Northeastern Brazil, comparing samples collected in areas of intensive tilapia (Oreochromis niloticus) farming to samples from areas not directly impacted by aquaculture, in both the dry and the rainy season. METHODS: Between October 2010 and July 2011, data were collected on temperature, conductivity, pH, turbidity, salinity, chlorophyll a, dissolved oxygen, oxygen demand, total phosphorus and total nitrogen levels in the water column using a multiparametric probe at four different sampling locations. Physical and chemical differences between the four locations were evaluated with the Kruskal-Wallis (KW) test and Dunn's post test, while the t test, followed by Welchʼs correction, was used to compare samples collected in different seasons. RESULTS: No influence of intensive aquaculture was detected when comparing sampling locations near fish farms (180C and 300C) to locations not directly impacted by aquaculture (LIMN1, near the dam, and LIMN2, near the debouch of the São Gonçalo river). However, the sampling locations differed significantly (p

The relationship between functional and taxonomic diversity is a major issue in ecology. Biodiversity in aquatic environments is strongly influenced by environmental gradients that act as dispersion and niche barriers. Environmental conditions act as filters to select functional traits, but biotic interactions also play a role in assemblage structure. In headwater streams, the relationship between functional and taxonomic diversity remains unclear. In this study we investigated how environmental conditions, taxonomic diversity and biotic interactions influence the spatial distribution of traits and functional diversity in stream fish species. Standardized sampling of fish species was carried out in 50 m sections of 16 streams located in rainforest enclaves in a semiarid region of Brazil (Caatinga biome). The functional diversity indices displayed different responses to the predictor variables used. Functional richness was mainly influenced by environmental conditions, while functional evenness was mostly determined by taxonomic diversity. On the other hand, functional dispersion was explained by a combination of environmental conditions and taxonomic diversity. The spatial distribution of fish species with the same functional traits was random, indicating that biotic interactions are not a strong predictor in these ecosystems. Channel width, pH and substrate were the most important variables in the spatial distribution of the functional traits of the fish species. Our results suggest that the functional structure of fish assemblages in headwater streams depends mainly on environmental conditions and taxonomic diversity.

This study analyzes the results, impacts and lessons learned from the support provided by ProVarzea to two fishery management projects developed in Manacapuru, Amazonas State, and Gurupa, Para State, between 2004 and 2006. During that period, said projects promoted institutional strengthening, emergence of leadership and improvements to the fishing management system, which was oriented to four species of characiformes and two species of siluriformes, with biomass values and gross revenues that have shown a tendency to increase, but with oscillation of the price per kilogram between the years evaluated only for the region of Gurupa. The fishery resources management model adopted by the institutions and communities supported by ProVarzea represents a new way to integrate the actions of the State with the organized civil society, thus contributing to the social, economic and environmental sustainability of fishing practices in the Amazon.

Flooding areas present high biological productivity and are inhabited by populations that practice agriculture-fishing activities, based on the multiple use of resources. The economicity of the system leads the riverines to territorial appropriation and the common dependence of the resources leads to the establishment of internal agreements, defining criteria of access and intensity of extraction. This study, through 244 interviews with fishermen and meetings at 16 communities of Low Solimões River, identified factors that influence on the magnitude and purpose of the fisheries, especially at common use fishing spots, describing appropriation mechanisms and conflicts. The studied area comprehends two systems of terra firme and one of flooding lakes. For subsistence and commercial fisheries was estimated the area, extension, and frequency of use for period of the year (dry/flood). Each community explored the fishing environments depending on the proximity and/or accessibility, revealing uses inside its territorial delimitations, with superposing on that explored for subsistence and commercial means. There are conflicts with commercial and sporting fisheries, fishermen out from the region and farmers. Prohibitions or access control don’t exist to the igapós systems, but informal rules regulating the use. Three sceneries are proposed for the integrated management of the systems in the area, due to the diversity of environments and interests of the involved groups Regiões de várzea apresentam alta produtividade biológica e são habitadas por populações que praticam atividades agropesqueiras, baseadas no uso múltiplo dos recursos. A economicidade do sistema conduz os ribeirinhos à apropriação de territórios e a dependência conjunta dos recursos ao estabelecimento de acordos internos, definindo-se critérios de acesso e intensidades de extração. Este estudo, por meio de 244 entrevistas com pescadores e reuniões em 16 comunidades do baixo Solimões, identificou fatores que influenciam na magnitude e finalidade das pescarias, especialmente em pesqueiros de uso coletivo, descrevendo mecanismos de apropriação e conflitos. O trecho abriga dois sistemas de lagos de terra firme e um de lagos de várzea. Para pescarias de subsistência e comercial, foram estimadas área, extensão e frequência de uso por período do ano (seca/cheia). Cada comunidade explorou os ambientes de pesca de acordo com a proximidade e/ou acessibilidade, revelando uso dentro das delimitações territoriais, havendo sobreposição naqueles explorados para subsistência e comércio. Existem conflitos por pesca comercial, esportiva, com pescadores externos à comunidade e com fazendeiros. Não existem proibições ou controle de acesso aos igapós, mas regras informais. Para o manejo integrado na área de estudo, são propostos três cenários de atuação, considerando a diversidade de ambientes e os interesses dos grupos envolvidos

A pesca é atividade essencial para as comunidades ribeirinhas da Amazônia, sendo o peixe fonte primordial de proteína animal e importante componente na geração de renda. Devido às variações na abundância e distribuição das espécies de peixe como conseqüência do ciclo hidrológico na região, ocorre sazonalidade na atividade de pesca. Assim, este estudo teve por objetivo identificar quais fatores determinam o tempo de dedicação às pescarias de subsistência ou com fins comerciais, por ribeirinhos de áreas de várzea. Foram entrevistados 244 pescadores de 16 comunidades no Baixo Solimões, quantificados os volumes capturados de tipos de pescado, por período do ano (seca ou cheia), e identificados os ambientes de pesca, os aparelhos utilizados e a receita bruta gerada quando da venda do pescado. Os resultados mostraram que há tendência no aumento do número de pescadores comerciais à medida que se aproxima do centro urbano de Manacapuru, sendo dois os fatores determinantes da atividade pesqueira praticada com este fim: ambientais, pela disponibilidade e acesso à áreas de pesca, e econômicos, estimulada a venda do peixe pela proximidade de centros de comercialização, o que gera o envolvimento de maior número de agentes na pesca. Os igapós foram importantes para todas as comunidades, sendo os ambientes mais explorados no período de cheia para captura de pescado, fato que ressalta a importância de medidas para sua conservação. A pesca é atividade essencial para as comunidades ribeirinhas da Amazônia, sendo o peixe fonte primordial de proteína animal e importante componente na geração de renda. Devido às variações na abundância e distribuição das espécies de peixe como conseqüência do ciclo hidrológico na região, ocorre sazonalidade na atividade de pesca. Assim, este estudo teve por objetivo identificar quais fatores determinam o tempo de dedicação às pescarias de subsistência ou com fins comerciais, por ribeirinhos de áreas de várzea. Foram entrevistados 244 pescadores de 16 comunidades no Baixo Solimões, quantificados os volumes capturados de tipos de pescado, por período do ano (seca ou cheia), e identificados os ambientes de pesca, os aparelhos utilizados e a receita bruta gerada quando da venda do pescado. Os resultados mostraram que há tendência no aumento do número de pescadores comerciais à medida que se aproxima do centro urbano de Manacapuru, sendo dois os fatores determinantes da atividade pesqueira praticada com este fim: ambientais, pela disponibilidade e acesso à áreas de pesca, e econômicos, estimulada a venda do peixe pela proximidade de centros de comercialização, o que gera o envolvimento de maior número de agentes na pesca. Os igapós foram importantes para todas as comunidades, sendo os ambientes mais explorados no período de cheia para captura de pescado, fato que ressalta a importância de medidas para sua conservação.

This study evaluates the total length of tambaqui (Colossoma macropomum ) captured in the middle Solimões river and traded during seven years (1993, 1997 and 2000 to 2005) in the Tefé market, Amazon, Brazil. The Mamirauá Institute of Sustainable Development obtained measurements of the total lengths from 42207 individuals. The length average was 45.23 ± 6.29 cm (minim um of 13 cm and maximum of 105.5 cm ) and the mode was 45 cm . From the total tambaquis, 92.86% were smaller than 55 cm and 7.14% measured 58.24 ± 5.41 cm on average. Medium and standard deviation of the lengths recorded in all years showed sizes below the established by the environmental federal agency. The Kruskal Wallis test showed that there is no significant difference between the abundances and medium sizes of the captures during all months of the year. The historical data of the tambaqui fisheries for the middle Solimões region indicate that individuals of this species have been constantly captured at sizes below the minim um length of reproduction. Nine recommendations for tambaquis fisheries management in the region related to more efficient mechanisms of inspection, auto-ecology studies of the species, environmental protection, reduction of fishery pressure, diffusion and educational cam paigns that aim to correct exploitation of this resource are presented in this manuscript.

The Cabiunas Lagoon is a narrow water body that is perpendicular to the sea and isolated from it by a sandbank. Before 1991, the sandbank was sometimes opened for a few days by local residents, but at present seawater only enters by limited groundwater seepage or by overtopping the sea barrier in storms. In 1998 the Restinga de Jurubatiba National Park was established, including the Cabiu nas Lagoon. Studies on the structure and spatial distribution of the fish assemblage were performed between 1991 and 1994; we carried out one year (2001–2002) of monthly monitoring of the lagoon to identify spatiotemporal variations in the lagoon fish assemblage. The closed sandbank altered salinity content, and favoured oligohaline conditions and the increase of the aquatic macrophyte abundance, promoting freshwater species dominance and reduction of the marine dependent and some coastal lagoon resident species of fish adapted to paralic ecosystems. Two freshwater, two coastal lagoon resident, and five marine d...

The effects of a disturbance by sandbank opening on the fish fauna community were evaluated through a long-term study in the Imboassica coastal lagoon, Rio de Janeiro State, Brazil. The fish and salinity samples were conducted between 1993 and 2004, with the goal of characterizing the structure and effects of four sandbank openings on this community, such as resilience and resistance measurements. During three sandbank openings, between the years of 1993 and 1996, the resilience time of the fish community could not be identified due to the short time period between openings, their magnitude and the discontinuity of the fish sampling. Monitoring studies previously conducted between 1993 and 2004, indicated that factors structuring the fish fauna of Imboassica lagoon are due to salinity fluctuations, influenced by the sandbank openings to which this environment is subjected. These events were indicated by the recolonization of primary freshwater species, oligohaline salinity values, and small variations in the composition and abundance on the fish community. Due to the magnitude and frequency of the disturbance, the ichthyic populations available that enter the lagoon from the adjacent ocean plus the resistance of this environment to salinity variations, determined the resilience and resistance of the fish fauna in the Imboassica lagoon. Thus, the resilience of the fish fauna in this lagoon was indicated in groupings of: a) Spearman probability values lower than 0.05 between the pairs of communities pre and post-disturbance; b) presence of freshwater species that indicate resilience; c) salinity values varying between 0 and 5; and d) small alterations in the abundance of fish populations Indicadores de la influencia de salinidad en la resistencia y resiliencia de la ictiofauna en laguna costera tropical (sudoeste de Brasil). Los efectos del disturbio de cuatro aberturas de la barra de arena en la laguna costera Imboassica, localizada en el municipio de Macaé, estado de Río de Janeiro, Brasil, en la comunidad de peces fueron evaluados en un estudio a largo plazo. Entre los años 1993 y 2004, colectas de peces y valores de salinidad fueron obtenidos con el objetivo de caracterizar la estructura y los efectos de las aberturas de barra sobre esta comunidad, como medidas de resiliencia y resistencia. Durante las aberturas de la barra realizadas entre los años de 1993 y 1996, el tiempo de resiliencia de la comunidad no fue identificado debido a los cortos intervalos de aberturas, a la magnitud del disturbio y a la discontinuidad de los muestreos de peces. Estudios realizados entre 1993 y 2004 indicaron que los factores que estructuran la ictiofauna de la laguna Imboassica son consecuencia de las variaciones de la salinidad, influenciadas por las aberturas de la barra a que este ambiente es sometido. Estos eventos fueron indicados por la recolonización de las especies primarias de agua dulce, valores de salinidad oligohalinos y bajas alteraciones en la composición y abundancia de la comunidad de peces. Debido a la magnitud y frecuencia de los disturbios, las poblaciones evaluadas de peces que entran en la laguna provenientes del océano adyacente, más la resistencia de este ambiente a las variaciones de salinidad, determinan la resiliencia y resistencia de la fauna de peces en la laguna. Así, la resiliencia de la fauna íctica en la laguna Imboassica fue indicada por el conjunto de: a) valores de probabilidad de Spearman menores de 0.05 entre los pares de comunidades pre y pos disturbio; b) presencia de especies de peces de agua dulce indicadoras de resiliencia; c) intervalos de salinidad variando entre 0 y 5; y d) bajas alteraciones en la abundancia de las poblaciones de pece

Humid highland forest enclaves are remnants of Atlantic Forest found in tablelands within the Caatinga biome (Northeastern Brazil), which emerged during interglacial periods in the Pleistocene. These ecosystems have a highly diverse and endemic fish fauna. Most earlier surveys have focused on the tableland of Borborema (Pernambuco and Paraíba States). In this study we surveyed the fish fauna of the humid forest enclaves in the tablelands of Ibiapaba and Araripe, based on samples collected in the rainy season (March and April) between 2009 and 2014. The 45 sampling points covered rivers, streams and reservoirs in five river basins belonging to three ecoregions. The species were listed according to drainage divide, and endemism was determined for each ecoregion and for the Caatinga. Our area was more species-rich (n=59) than Borborema (n=27). The samples included five introduced species and 29 species endemic to the Caatinga (49.1% of the sampled species). The distribution of Parotocinclus haroldoi was expanded to the Mid-Northeastern Caatinga ecoregion (Timonha river basin, Ceará State). Our study intends to make a significant contribution to current knowledge of the ichthyofauna in humid highland forest enclaves of semiarid Northeastern Brazil, identified as a priority in the conservation of the biodiversity in the Caatinga. Resumo Florestas úmidas são enclaves de Mata Atlântica em regiões elevadas inseridas no bioma Caatinga que surgiram no Pleistoceno em eventos interglaciais. Esses ecossistemas abrigam alta diversidade de espécies para diversos táxons e elevadas taxas de endemismo. A maioria dos levantamentos de peixes nesses ecossistemas foi realizada no Planalto da Borborema, nos Estados de Pernambuco e Paraíba. Dessa forma, visando conhecer a ictiofauna de dois enclaves de florestas úmidas no nordeste brasileiro, foram feitas coletas no período chuvoso (Março e Abril) entre 2009 e 2014 no Planalto da Ibiapaba e na Chapada do Araripe. Foram amostrados 45 pontos em rios, riachos e reservatórios em cinco bacias hidrográficas e três ecorregiões. A lista de espécies por drenagem e o endemismo foi definido para cada ecorregião e para a Caatinga. A riqueza de peixes (59 espécies) foi superior quando comparada a dos enclaves da Borborema (27), com cinco espécies introduzidas e 29 endêmicas para a Caatinga, o que representa 49,1% das espécies capturadas. Destaca-se a expansão de ocorrência de Parotocinclus haroldoi para a ecorregião do Mid-Northeastern Caatinga, na microbacia do rio Timonha, no Estado do Ceará. Este estudo pretende contribuir com informações inéditas para o conhecimento ictiofaunístico dos ecossistemas aquáticos dos brejos de alitude do semiárido brasileiro, apontadas como prioritárias para conservação da biodiversidade da Caatinga.

Aim:To evaluate possible nycthemeral and seasonal temporal patterns in fish assemblage associated with limnological aspects and biotic factors in two reservoirs in semarid Northeastern Brazil.MethodsFish were sampled with gillnets in nycthemeral cycles throughout the dry and rainy season in two reservoirs (Paulo Sarasate/PS and Edson Queiroz/EQ). The stomach contents of the predator species were surveyed. The limnological variables were submitted to principal components analysis, while their relation to fish abundance was determined by canonical correspondence analysis. Temporal patterns in relative fish species abundance were detected with nMDS.ResultsTemperature and dissolved oxygen levels segregated the reservoirs physico-chemically. Turbidity and chlorophyll-a levels differed between seasons, and the relative abundance of species differed between the reservoirs. Predators were more abundant in PS, while detritivores were more abundant in EQ. Triportheus signatusand Plagioscion squamosissimus were the most abundant species in both reservoirs. In general, predator abundance was positively associated with high temperature and dissolved oxygen (PS>EQ) and negatively associated with turbidity. The activity patterns of P. squamosissimus could not be explained by fluctuations in environmental variables. Non-predators tended to cluster around the vectors chlorophyll-a, pH and turbidity. Predators had a more diversified diet in PS in accordance with food availability, while predators in EQ ate only fish and shrimp. Nycthemeral patterns varied for the same species depending on the reservoir. Generally, in PS predators were more active during daylight hours while non-predators were more active after dark. However, in EQ predators and non-predators displayed similar nycthemeral activity patterns. Regardless of the reservoir, predators were more abundant in the rainy season. No seasonal trend was observed for non-predators.ConclusionsLimnological differences between PS and EQ influenced temporal species abundance patterns. The species distribution was determined by predation conditions and physiological attributes. Objetivo:Avaliar os possíveis padrões temporais nictemerais e sazonais na assembleia íctica em relação a aspectos limnológicos e fatores bióticos em dois reservatórios no semiárido Nordeste do Brasil.MétodosPeixes foram amostrados com redes de espera em ciclos nictemerais nos períodos seco e chuvoso em dois reservatórios (Paulo Sarasate /PS e Edson Queiroz /EQ). O conteúdo estomacal das espécies predadoras foi avaliado. As variáveis limnológicas foram submetidas a uma PCA, enquanto suas relações com a abundância de peixes foi determinada por uma CCA. Padrões temporais relativos à abundância de espécies de peixes foram detectados com nMDS.ResultadosTemperatura e oxigênio dissolvido segregaram fisico-quimicamente os reservatórios. Níveis de turbidez e clorofila-a diferiram entre os períodos do ano, e a abundância relativa das espécies diferiram entre os reservatórios. Predadores foram mais abundantes no PS, enquanto detritívoros foram mais abundantes no EQ. Triportheus signatus e Plagioscion squamosissimus foram as espécies mais abundantes em ambos os reservatórios. No geral, a abundância de predadores foi positivamente relacionada com altas temperaturas e oxigênio dissolvido (PS>EQ) e negativamente associada com turbidez. Os padrões de atividades de P. squamosissimus não podem ser explicados por flutuações nas variáveis ambientais. Espécies não predadoras tenderam a se agruparem aos vetores clorofila-a, pH e turbidez. Predadores apresentaram dieta mais diversificada no PS de acordo com a disponibilidade de alimento, enquanto predadores no EQ consumiram somente peixe e camarão. Padrões nictemerais variaram para algumas espécies dependendo do reservatório. Em geral, no PS predadores foram mais ativos durante as horas iluminadas do dia, enquanto não predadores foram mais ativos após o escurecer. Entretanto, no EQ predadores e não predadores mostraram padrões nictemerais de atividades similares. Independentemente do reservatório, predadores foram mais abundantes no período chuvoso. Nenhuma tendência sazonal foi observada para espécies não predadoras.ConclusõesDiferenças limnológicas entre PS e EQ influenciaram padrões temporais na abundância das espécies.

Few studies have been published on the taxonomy, biology and ecology of the fish fauna of the rivers and reservoirs from the Brazilian Caatinga. Considering the importance of fish surveys as subsidies for future studies and fishing resources management, the purpose of the present study was to assess the fish assemblage of the two largest reservoirs in the middle Acaraú river basin, the Paulo Sarasate and the Edson Queiroz reservoirs, state of Ceará, Northeastern Brazil. Eight nycthemeral samplings were performed with gillnets (mesh size ranging from 3 to 12 cm between opposite knots) during rainy and dry season between 2010 and 2012. We captured 1,626 specimens belonging to three orders, nine families and 17 species, six of which are endemic to the Caatinga. Approximately 30% of the species observed were non-native and had been introduced for stocking purposes.

Regiões de várzea apresentam alta produtividade biológica e são habitadas por populações que praticam atividades agropesqueiras, baseadas no uso múltiplo dos recursos. A economicidade do sistema conduz os ribeirinhos à apropriação de territórios e a dependência conjunta dos recursos ao estabelecimento de acordos internos, definindo-se critérios de acesso e intensidades de extração. Este estudo, por meio de 244 entrevistas com pescadores e reuniões em 16 comunidades do baixo Solimões, identificou fatores que influenciam na magnitude e finalidade das pescarias, especialmente em pesqueiros de uso coletivo, descrevendo mecanismos de apropriação e conflitos. O trecho abriga dois sistemas de lagos de terra firme e um de lagos de várzea. Para pescarias de subsistência e comercial, foram estimadas área, extensão e frequência de uso por período do ano (seca/cheia). Cada comunidade explorou os ambientes de pesca de acordo com a proximidade e/ou acessibilidade, revelando uso dentro das delimitações territoriais, havendo sobreposição naqueles explorados para subsistência e comércio. Existem conflitos por pesca comercial, esportiva, com pescadores externos à comunidade e com fazendeiros. Não existem proibições ou controle de acesso aos igapós, mas regras informais. Para o manejo integrado na área de estudo, são propostos três cenários de atuação, considerando a diversidade de ambientes e os interesses dos grupos envolvidos. Flooding areas present high biological productivity and are inhabited by populations that practice agriculture-fishing activities, based on the multiple use of resources. The economicity of the system leads the riverines to territorial appropriation and the common dependence of the resources leads to the establishment of internal agreements, defining criteria of access and intensity of extraction. This study, through 244 interviews with fishermen and meetings at 16 communities of Low Solimões River, identified factors that influence on the magnitude and purpose of the fisheries, especially at common use fishing spots, describing appropriation mechanisms and conflicts. The studied area comprehends two systems of terra firme and one of flooding lakes. For subsistence and commercial fisheries was estimated the area, extension, and frequency of use for period of the year (dry/flood). Each community explored the fishing environments depending on the proximity and/or accessibility, revealing uses inside its territorial delimitations, with superposing on that explored for subsistence and commercial means. There are conflicts with commercial and sporting fisheries, fishermen out from the region and farmers. Prohibitions or access control don't exist to the igapós systems, but informal rules regulating the use. Three sceneries are proposed for the integrated management of the systems in the area, due to the diversity of environments and interests of the involved groups.

Segregation in the use of the water column by two congeneric species of Characidae, Hyphessobrycon bifasciatus and H. luetkenii, was investigated through underwater observations in the Cabiúnas coastal lagoon in northeastern Rio de Janeiro, Brazil. The use of the water column by the two species differed significantly. Hyphessobrycon luetkenii occupied mainly the uppermost stratum, with 79% of the observations within 20 cm of the surface; whereas H. bifasciatus was more common between 20 cm and 40 cm below the surface (55% of the observations). Predation pressure, macrophyte cover and nutrient distribution may influence this vertical segregation. A segregação na coluna d'água por duas espécies congenéricas de caracídeos, Hyphessobrycon bifasciatus e H. luetkenii, foi investigada através de observações subaquáticas na lagoa costeira Cabiúnas, nordeste do Rio de Janeiro. O padrão do uso da coluna d'água diferiu significativamente. Hyphessobrycon luetkenii ocupou principalmente o estrato superior, com 79% das observações até 20 cm da superfície, enquanto H. bifasciatus foi mais comum entre 20 e 40 cm abaixo da superfície (55% das observações). Pressão de predação e distribuição das macrófitas e dos nutrientes são fatores que poderiam influenciar a segregação vertical entre as espécies de Hyphessobrycon.

Este estudio evalúa características del consumo de alimentos de 15 familias de la villa de pescadores de Emboaca (Estado de Ceará, nordeste del Brazil), que registraron su consumo de proteínas por 45 días (2017-2018). Pescado y pollo fueran equivalentes en la frecuencia de consumo, constituyendo 82% de la proteína animal en las comidas familiares. Pescados representan un consumo anual de alrededor de 52 kg per capita. Al menos 14 especies de pescados integraron las comidas de las familias avaluadas, con énfasis en ariacó, biquara, arraia, cavala y serra, que en conjunto concentraron el 76% de los registros. El pescado de origen marina es considerado una importante fuente de proteína animal, como base económica para las familias de Emboaca. El estudio indica que los pobladores de la comunidad se mantienen resistentes y resilientes ante a los cambios regionales impulsados por el turismo creciente y las adversidades impuestas por la pandemia del COVID-19. Concluimos que la pesca artesanal y el consumo de peces marinos son fuertes agregadores comunitarios, fundamentales para mantener la seguridade alimentar y las prácticas culturales locales.