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| Registros recuperados: 1.204 | |
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| Abelha,Milza Celi Fedatto; Goulart,Erivelto; Kashiwaqui,Elaine Antoniassi Luiz; Silva,Marlene Rodrigues da. |
| Aspects of the feeding ecology of a small characin, Astyanax paranae, were studied during 1996/1997 and 1998/1999 in the Alagados Reservoir, Paraná, Brazil (25º01'50.0'' S; 050º03'41.9'' W). Fishes were quarterly captured from the reservoir's riverine and lacustrine zones and stomachs contents of 711 adult individuals were analyzed by volumetric method. Species' feeding spectrum and spatial, temporal and sexual variations on diet were evaluated. Data matrix was summarized by detrented correspondence analysis (DCA) and the axes scores from DCA were used as variables in one-way ANOVA of null models to test diet variations. Astyanax paranae fed on detritus/sediment, plant matter, algae and aquatic and terrestrial invertebrates. The time-space prevalence of... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Fish; Feeding; Dam; Detritivory; Freshwater. |
| Ano: 2006 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252006000300006 |
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| Abilhoa,Vinícius; Bornatowski,Hugo; Otto,Gislaine. |
| Feeding habits of the characin Hollandichthys multifasciatus were investigated. Samplings were made between March 2004 and February 2005 in two black water streams of the coastal Atlantic rainforest in southern Brazil. The diet, evaluated by qualitative and quantitative methods, included aquatic and terrestrial insects, decapods, oligochaetes, plants and spiders. Large individuals feed mainly on plants, terrestrial insects, and spiders, whereas small fish feed basically on plants and oligochaetes. The species showed an omnivorous feeding habit, and its diet was composed of autochthonous (mainly oligochaetes) and allochthonous (plants and terrestrial insects) material. |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Characin; Diet Feeding ecology Freshwater Neotropics. |
| Ano: 2009 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252009000300008 |
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| Abilhoa,Vinícius; Vitule,Jean Ricardo Simões; Bornatowski,Hugo. |
| Feeding habits of the killifish Rivulus luelingi collected in a black water stream of the Coastal Atlantic Rainforest in southern Brazil were investigated. Eight samplings were made between April 2003 and January 2004. The diet, assessed through a similarity matrix with the estimated contribution values of food items, included microcrustaceans, aquatic immature insects (larvae and pupae), aquatic adult insects, terrestrial insects, insect fragments, spiders, and plant fragments. Differences in the diet according to temporal variations (months) were registered, but changes related with size classes evaluated and high/low precipitation period were not observed. The species presented an insectivorous feeding habit, and its diet in the studied stream was... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Diet; Feeding habits; Freshwater; Killifish; Neotropics. |
| Ano: 2010 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252010000400010 |
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| Abreu,Janessa S.; Brinn,Richard P.; Gomes,Levy C.; McComb,Dawn Michelle; Baldisserotto,Bernardo; Zaiden,Sérgio F.; Urbinati,Elisabeth C.; Marcon,Jaydione L.. |
| We investigated the use of beta 1,3 glucan as an imunostimulant during a transport experiment to determine the effects upon the stress response of the pencilfish (Nannostomus trifasciatus). Pencilfish were fed for seven days with different concentrations of beta 1,3 glucan: 0.0% (control); 0.01%; 0.1% and 0.5% of beta 1,3 glucan per kg of feed-1. Fish were then transported for 24 hours by boat from Barcelos to Manaus. The highest dose of beta 1,3 glucan in the food increased Na+influx after 12 hours of transport and 0.1 and 0.5% beta 1,3 glucan maintained the flux of both ions close to zero at 24 hours. All doses of beta 1,3 glucan reduced K+ loss significantly in the beginning of the transport, but after 12 to 24 hours did not. No significant differences... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Cortisol; Immunostimulant; Ion fluxes; Ornamental fish; Rio Negro basin. |
| Ano: 2014 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252014000300623 |
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| Afonso,André S.; Cantareli,Carlos V.; Levy,Rafael P.; Veras,Leonardo B.. |
| ABSTRACT Mating events and aggregations of vulnerable nurse sharks Ginglymostoma cirratum were recorded in the insular protected area of Fernando de Noronha (FEN), Brazil, between April and August 2015. Female sharks were observed clustering in groups of up to 14 individuals in shallow water adjacent to the shore. Several evasive mating behaviours in the presence of males were noticed, including shoreward movement, positioning ventral side up at the sea surface with emerged pectoral and pelvic fins, body rolling and caudal fin thrashing. Fresh bite marks indicative of male courtship and coupling attempts were visible in female's pectoral and caudal fins. Altogether, the observed behaviours match previous reports of non-cooperative female nurse sharks... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Bite marks; Copulation; Fernando de Noronha; Marine protected areas; Reproductive aggregations. |
| Ano: 2016 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252016000400207 |
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| Agostinho,Angelo Antonio; Agostinho,Carlos Sergio; Pelicice,Fernando Mayer; Marques,Elineide Eugênio. |
| Fish ladders are a strategy for conserving biodiversity, as they can provide connectivity between fragmented habitats and reduce predation on shoals that accumulate immediately below dams. Although the impact of predation downstream of reservoirs has been investigated, especially in juvenile salmonids during their downstream movements, nothing is known about predation on Neotropical fish in the attraction and containment areas commonly found in translocation facilities. This study analysed predation in a fish passage system at the Lajeado Dam on the Tocantins River in Brazil. The abundance, distribution, and the permanence (time spent) of large predatory fish along the ladder, the injuries imposed by piranhas during passage and the presence of other... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Dam; Fish migration; Fish pass; Piscivores; Serrasalmus. |
| Ano: 2012 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252012000400001 |
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| Agostinho,Angelo Antônio; Marques,Elineide Eugênio; Agostinho,Carlos Sérgio; Almeida,Deusimar Augusto de; Oliveira,Rafael José de; Melo,Jussiclene Rodrigues Bezerra de. |
| Fish ladders are generally conceived to reestablish connectivity among critical habitats for migratory species, thus mitigating the impacts of the blockage of migration routes by dams. If this management tool is to be meaningful for conserving fish species, it must provide a fully permeable connection and assure both upward and downward movements. However, because reservoirs have very different hydrodynamics than the original river, it is expected that, at least in the inner area, they may constitute an additional barrier to this movement, especially for descending fish. Thus, the present study sought to determine if migratory fish and their offspring disperse downstream from the dam after ascending a ladder and spawning in the upper reaches of a basin. To... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Fish passage; Reservoir; Downstream migration; Larvae drift; Rio Tocantins. |
| Ano: 2007 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252007000200005 |
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| Agostinho,Carlos Sérgio; Agostinho,Angelo Antônio; Pelicice,Fernando; Almeida,Deusimar Augusto de; Marques,Elineide Eugênio. |
| Although dozens of fish ladders have been constructed at dams of Brazilian reservoirs, there are few studies evaluating their efficiency as a tool for the conservation of Neotropical ichthyofauna, especially for migratory species. Therefore, the present study evaluated the selectivity of the species that entered and ascended the fish ladder located next to Lajeado Dam (Luis Eduardo Magalhães Hydroelectric Power Plant) on the Tocantins River. Samples were taken monthly from November, 2002 through October, 2003, in the resting pools of the ladder, using cast nets, and in the downstream stretch, using gillnets. The selectivity of the ladder in attracting fish was evaluated by comparing the occurrence, relative abundance, dominance and the congruence of... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Migratory fish; Fish conservation; Biodiversity; Reservoir; Lajeado Dam; Tocantins River. |
| Ano: 2007 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252007000200015 |
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| Aguilar-Betancourt,Consuelo M.; González-Sansón,Gaspar; Flores-Ortega,Juan R.; Kosonoy-Aceves,Daniel; Lucano-Ramírez,Gabriela; Ruiz-Ramírez,Salvador; Padilla-Gutierrez,Sandra C.; Curry,R. Allen. |
| ABSTRACT The main goal of this research was to investigate the differences in diet composition among three species of the genus Lutjanus inhabiting a coastal lagoon as juveniles. The working hypothesis was that these species feed on a common base of food resources and therefore, some niche overlap is present in terms of general diet composition. However, changes in the trophic niche with size and differences in some morphological traits among species explain observed differences in diet. Fish were collected during 42 sampling trips conducted regularly from February 2011 to January 2012 using several types of fishing gear. Total number of analyzed stomachs was 288 for Lutjanus argentiventris from 2.3 to 19.9 cm total length (TL); 178 for Lutjanus colorado... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Estuarine habitat; Feeding; Lutjanidae; Ontogenic changes; Trophic morphology. |
| Ano: 2017 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252017000400211 |
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| Akama,Alberto; Ferraris, Jr.,Carl J.. |
| A new species of auchenipterid catfish, Entomocorus melaphareus, is described. The new species is readily distinguished from its two congeners, Entomocorus benjamini Eigenmann, 1917, and E. gameroi Mago Leccia, 1983, by having darkly pigmented, rather than hyaline, pectoral and pelvic fins. Entomocorus melaphareus is known from the margins of the lower and middle rio Amazonas, and is the only species of the genus known from the main channel of that river. |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Auchenipteridae; Neotropical; Entomocorus benjamini; Entomocorus gameroi. |
| Ano: 2003 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252003000200001 |
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| Albert,James S.; Val,Pedro; Hoorn,Carina. |
| ABSTRACT We review geological evidence on the origin of the modern transcontinental Amazon River, and the paleogeographic history of riverine connections among the principal sedimentary basins of northern South America through the Neogene. Data are reviewed from new geochronological datasets using radiogenic and stable isotopes, and from traditional geochronological methods, including sedimentology, structural mapping, sonic and seismic logging, and biostratigraphy. The modern Amazon River and the continental-scale Amazon drainage basin were assembled during the late Miocene and Pliocene, via some of the largest purported river capture events in Earth history. Andean sediments are first recorded in the Amazon Fan at about 10.1-9.4 Ma, with a large increase... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Biostratigraphy; Geochronology; Landscape Evolution Model; River capture; Transcontinental Amazon. |
| Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252018000300306 |
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| Albrecht,Miriam P.; Pellegrini-Caramaschi,Erica. |
| The feeding ecology of Leporinus taeniofasciatus in the upper rio Tocantins was characterized before (river phase) and after (reservoir phase) its impoundment by the Serra da Mesa Hydroelectric Dam. The importance of each food item was given by the Alimentary Index (IAi), which combines the frequency of occurrence and volumetric methods. A significant difference in the diet of L. taeniofasciatus between seasons in the river phase, detected by a multivariate analysis of variance, was not kept when the reservoir was formed. Its feeding activity, verified through the percentage of stomachs with different degrees of fullness, was not affected by the impoundment. Leporinus taeniofasciatus was able to incorporate terrestrial food items to its diet when they... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Diet; Fish; Neotropical; Reservoir. |
| Ano: 2003 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252003000100006 |
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| Registros recuperados: 1.204 | |
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