|
|
|
Registros recuperados: 1.204 | |
|
| |
|
|
Olinger,Charles T.; Peoples,Brandon K.; Frimpong,Emmanuel A.. |
Abstract This study examined reproductive traits and growth rates of Heterandria bimaculata (Poeciliidae) in Cusuco National Park (CNP), a cloud forest reserve in northern Honduras, Central America. In CNP, H. bimaculata occurs in the absence of other fish species and major invertebrate predators along an approximately 1000 m elevation gradient. This allowed for the examination of trait variation along the gradient without the confounding effects of interspecific interactions or habitat patchiness. Heterandria bimaculata exhibited traits characteristic of a low-predation environment: balanced sex ratio, slow growth, late maturity and large female size. Females produced more, smaller eggs from upstream to downstream, but overall reproductive allocation... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Central America; Fecundity; Growth rate; Livebearer; Offspring size. |
Ano: 2016 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252016000100003 |
| |
|
|
Lopes,Carla Martins; Almeida,Fernanda Simões de; Orsi,Mário Luís; Britto,Sandro Geraldo de Castro; Sirol,Rodolfo Nardez; Sodré,Leda Maria Koelblinger. |
The aim of this study, utilizing RAPD techniques, was to determine the genetic variability of Salminus brasiliensis groups collected at passage ladders of the hydroelectric plants (HEP) Canoas I and Canoas II - Paranapanema River (Brazil), as well as to estimate the population structure through different parameters of genetic diversity. The data obtained allowed us to conclude that S. brasiliensis of the Canoas Complex has a moderate index of genetic variability ( > 42.00%) when compared to that of other migratory fish species. All genetic diversity analyses (distance = 0.015 and genetic identity = 0.985, F ST =0.018, AMOVA) were signs of low genetic differentiation, and they led to the clustering of S. brasiliensis from Canoas I and Canoas II. This... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Fish transposition; Geneticdiversity; RAPD. |
Ano: 2007 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252007000200006 |
| |
|
|
Liedke,Ana M.R.; Pinheiro,Hudson T.; Floeter,Sergio R.; Bernardi,Giacomo. |
ABSTRACT Among the four butterflyfishes of the genus Chaetodon present in the western Atlantic, the banded butterflyfish Chaetodon striatus has the largest distribution range, spanning 44 degrees of latitude (from Massachusetts, USA to Santa Catarina, Brazil). Although the ecology of the banded butterflyfish has been well studied over its entire range, nothing is known about its phylogeography and how biogeographic barriers structure its populations. To assess the level of genetic connectivity among populations from distinct biogeographic provinces and environmental conditions, we collected samples from seven localities: Puerto Rico, in the Caribbean, and Tamandaré, Salvador, Abrolhos, Trindade Island, Arraial do Cabo and Florianópolis, in Brazil. One... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Biogeography; Evolution; Mitochondrial Genes; Nuclear Genes; Reef Fish. |
Ano: 2020 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252020000100205 |
| |
|
| |
|
|
Godinho,Alexandre Lima; Godinho,Hugo Pereira. |
ABSTRACT Pirá, Conorhynchos conirostris (Valenciennes, 1840), a large migratory catfish endemic to the São Francisco River (SFR), is listed as threatened in the red lists of both Brazil and the state of Minas Gerais. Although fishing for pirá has been prohibited, it is still an important fishery resource, particularly in the middle SFR. We used historical and current occurrence and abundance data regarding pirá to determine if it meets the IUCN criteria of a threatened species. Pirá occurs in the main course of the SFR as well as in its major tributaries. Unlike the most well-known migratory fishes of the SFR, pirá does not use floodplain lakes as nurseries. In the first half of the 20th century, pirá occurred from the upper to the lower SFR. Currently, it... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: IUCN; Red list; São Francisco River; Threatened fish. |
Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252018000100221 |
| |
|
| |
|
| |
|
| |
|
|
Daga,Vanessa Salete; Gogola,Tatiane Mary; Sanches,Paulo Vanderlei; Baumgartner,Gilmar; Baumgartner,Dirceu; Piana,Pitágoras Augusto; Gubiani,Éder André; Delariva,Rosilene Luciana. |
The objective of this study was to assess the abundance, attributes of assemblages, and spatial and temporal distributions of fish larvae and their relationships with some abiotic variables in two floodplain lakes with different degrees of connection to the Paraná River in Ilha Grande National Park, PR, Brazil. Four sampling sites were chosen, two in each floodplain lake. Night samples were taken with plankton nets during three spawning seasons (monthly, from October to March) from 2001 to 2005. The highest diversity and abundance were recorded at Saraiva Lake, with 25 taxa being identified. In Xambrê Lake, only sedentary species were captured, and the most abundant species were Plagioscion squamosissimus and Hypophthalmus edentatus. The greatest abundance... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Ichthyoplankton; Fish reproduction; Parque Nacional de Ilha Grande; Upper Paraná River. |
Ano: 2009 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252009000300010 |
| |
|
| |
|
|
Prado,Marina Rodrigues do; Carvalho,Débora Reis de; Alves,Carlos Bernardo Mascarenhas; Moreira,Marcelo Zacharias; Pompeu,Paulo Santos. |
ABSTRACT This study aimed to evaluate if the presence of pollutants promotes changes in feeding habits of fish species from different trophic guilds: the detritivorous species, Hypostomus francisci, and the piscivorous, Hoplias intermedius. Both species were sampled at 12 sites (with different degrees of pollution) in the Rio das Velhas basin, which is heavily polluted by domestic and industrial sewage from the Metropolitan Region of Belo Horizonte (MRBH). Stable isotope analyses of carbon (δ13C) and nitrogen (δ15N) of fish tissue and the main food resources were performed. Fishes from both trophic guilds altered their diets in degraded environments, but the detritivorous species showed greater trophic plasticity. The isotopic niche of both trophic guilds... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Detritivorous; Hoplias intermedius; Hypostomus francisci; Piscivorous; Stable isotopes. |
Ano: 2020 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252020000100203 |
| |
|
|
Paschoalini,Alessandro Loureiro; Perini,Violeta da Rocha; Ribeiro,Dirceu Marzulo; Formagio,Paulo Sérgio; Rizzo,Elizete; Bazzoli,Nilo. |
The alterations to the hydrologic regime downstream from hydroelectric dams may cause an impact on the reproductive success of fishes. This study aimed to analyse the influence of the physical and chemical parameters of the water of the Grande and Pardo Rivers on gonadal maturation, oocyte diameter, follicular atresia and biological indices of Pimelodus maculatus collected from three river sections: Grande River, downstream from the Porto Colômbia dam (S1), Grande River, downstream from the confluence with the Pardo River (S2) and in the Pardo River channel (S3). Males and females captured in S1 presented significantly higher average values for total length and body weight than those captured in S2 and S3. The gonadosomatic index values were significantly... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Abiotic factors; Dam impacts; Environmental impacts; Gonadosomatic index. |
Ano: 2013 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252013000300615 |
| |
|
| |
|
|
Nakayama,Celeste Mutuko; Feldberg,Eliana; Bertollo,Luiz Antonio Carlos. |
Six species of Serrasalmidae from the central Amazon, representatives of the genera Serrasalmus (S. elongatus, S. maculatus, S. cf. rhombeus, and S. rhombeus), Pygocentrus (P. nattereri), and Colossoma (C. macropomum), were analyzed regarding the distribution of the Ag-NORs, C-positive heterochromatin and 18S and 5S rRNA genes on the chromosomes. All specimens had 2n = 60 chromosomes, except S. cf. rhombeus, with 2n = 58, and C. macropomum with 2n = 54 chromosomes. The Ag-NORs were multiple and located on the short arms of subtelo-acrocentric chromosomes in all Serrasalmus species and in P. nattereri, but were found on metacentric chromosomes in C. macropomum. The 18S rDNA sites were usually coincident with Ag-NORs, although some species had a higher... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Chromosomal evolution; Fish; Heterochromatin; Piranhas; Ribosomal genes. |
Ano: 2012 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252012000100005 |
| |
|
| |
|
|
Novakowski,Gisele Caroline; Hahn,Norma Segatti; Fugi,Rosemara. |
We assessed the trophic structure of the fish fauna in Sinhá Mariana pond, Mato Grosso State, from March 2000 to February 2001. The aim was to determine the feeding patterns of the fish species during the rainy and dry seasons. The diets of 26 species (1,294 stomach contents) were determined by the volumetric method. Insects and fish were the most important food resources: insects were the dominant food of 23% and 27% of the species, respectively, in the rainy and dry season, and fish was the dominant item for 31% of the species in both seasons. Cluster analysis (Euclidean Distance) identified seven trophic guilds in the rainy season (detritivores, herbivores, insectivores, lepidophages, omnivores, piscivores and planktivores), and five trophic guilds in... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Fishes; Feeding overlap; Seasonal analysis; Pond. |
Ano: 2008 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252008000400004 |
| |
|
| |
|
| |
|
| |
Registros recuperados: 1.204 | |
|
|
|