Consulta: subjectFacets:"Diel cycle"
Registros recuperados: 6
Data/hora: 09/06/2024 14:31:21

Schooling behaviour of small pelagic fish: phenotypic expression of independent stimuli
Provedor de dados: 5
Autores: Brehmer, Patrice; Gerlotto, François; Laurent, Charline; Cotel, Pascal; Achury, Alina; Samb, Birane.
We compared echo sounder measurements of fish schools on Venezuelan and Senegalese coastal shelves. In both areas Sardinella aurita was the predominant aggregative species; the stocks are known to be genetically independent. Persistent school typology is described by analysing 7 acoustic surveys in Venezuela and comparing with pioneer observations in Senegal. The echo types encountered in both countries were comparable, with S. aurita and their associated species having comparable schooling behaviour. School morphology appears to be more related to species than to global characteristics of their ecosystems, as fish school descriptors were similar for both stocks. Nevertheless, S. aurita may adopt different school morphologies. Differentiation between day...
Tipo: Text
Palavras-chave: Small pelagic fish; Schooling; Phenotypic expression; In situ observations; Echo type; Diel cycle; Behaviour.
Ano: 2007
URL: http://archimer.ifremer.fr/doc/2007/publication-2536.pdf

Acoustic accelerometry reveals diel activity patterns in premigratory Port Jackson sharks
Provedor de dados: 5
Autores: Kadar, Julianna; Ladds, Monique; Mourier, Johann; Day, Joanna; Brown, Culum.
Distinguishing the factors that influence activity within a species advances understanding of their behavior and ecology. Continuous observation in the marine environment is not feasible but biotelemetry devices provide an opportunity for detailed analysis of movements and activity patterns. This study investigated the detail that calibration of accelerometers measuring root mean square (RMS) acceleration with video footage can add to understanding the activity patterns of male and female Port Jackson sharks (Heterodontus portusjacksoni) in a captive environment. Linear regression was used to relate RMS acceleration output to time‐matched behavior captured on video to quantify diel activity patterns. To validate captive data, diel patterns from captive...
Tipo: Text
Palavras-chave: Accelerometer; Activity pattern; Diel cycle; Migratory restlessness; Port Jackson shark; Root mean square acceleration.
Ano: 2019
URL: https://archimer.ifremer.fr/doc/00508/61990/66104.pdf

Macrobenthic communities on the continental shelf of Cote-d'Ivoire. Seasonal and diel cycles in relation to hydroclimate
Provedor de dados: 5
Autores: Le Loeuff, P; Intes, A.
Benthic communities of the shrimp (Penaeus notialis) grounds off Grand-Bassam, Cote-d'Ivoire, exhibit distinct variations, correlated to annual changes in hydroclimate, characterized by warm and cold (upwelling) seasons. These changes appear to be the result of the well-defined reproduction periods of many short-living benthic species, as clearly shown by the peaks of abundance in the samples, at different times of the year, but quite often at the end of the cold and the beginning of the warm seasons (September-November). Many species show marked diel rhythms, either diurnal (pagurids, brachyurans) or nocturnal (macrurans, brachyurans, molluscs), so that the species composition displays distinct differences between day and night samples (February 1970...
Tipo: Text
Palavras-chave: Faune benthique; Golfe de Guinée; Cycle saisonnier; Cycle circadien; Perturbation; Benthic fauna; Gulf of Guinea; Seasonal cycle; Diel cycle; Perturbation.
Ano: 1999
URL: http://archimer.ifremer.fr/doc/00325/43601/43985.pdf

Dark metabolism and carbon-nitrogen uncoupling in the toxic dinoflagellate Alexandrium catenella (Dinophyceae)
Provedor de dados: 5
Autores: Jauzein, Cecile; Collos, Yves; Laabir, Mohamed; Vaquer, Andre.
Uptake rates of three potential N-sources (ammonium, nitrate and N-urea) and two potential C-sources (HCO(3)(-) and C-urea) were estimated during growth of Alexandrium catenella in both light and dark phases. According to the variations observed in (13)C-isotopic ratio, A. catenella cells were not able to use C-urea. Furthermore, decreases in (13)C cell content during darkness revealed a probably high involvement of C recently fixed in dark respiration. Dark N-uptake capacities of A. catenella were characterized by dark/light uptake ratio of 27%, 43% and 65% for NO(3)(-), NH(4)(+) and N-urea, respectively. An accumulation of C-rich compounds during the light period was highlighted through strong diel variations in C:N ratio and would provide C and energy...
Tipo: Text
Palavras-chave: Diel cycle; Dark uptake; Nitrogen; Carbon; Uncoupling; Alexandrium catenella.
Ano: 2011
URL: http://archimer.ifremer.fr/doc/00056/16699/14199.pdf

Alimentação e ciclo alimentar diário de Hoplosternum littorale (Hancock) (Siluriformes, Callichthyidae) nas lagoas Guaraná e Patos da planície do alto rio Paraná, Brasil
Provedor de dados: 104
Autores: Hahn,Norma Segatti; Almeida,Vera Lúcia Lescano de; Luz,Karla Danielle Gaspar da.
Hoplosternum Uttorale (Hancock, 1828) is an abundant species in the lagoons of the upper Paraná river floodplain. This species was sampled in Patos and Guaraná lagoons in the flood period (November/92-May/93) and low water period (June-October/93). To analyse food contents in the diet were analysed stomach of 91 adults. Twenty seven food items were recorded, among them, Testaceae, Nematoda, microcrustaceans, quironomids and organic detritus were predominant. These items allows to characterize the species as bentivore. To study feeding activity were analized 565 adults stomach contents. Food intake was more intense during flooding. Considering diel variation, the species started to eat during dusk, increasing during night, stopping to eat during daytime.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Siluriformes; Callichthyidae; Hoplosternum Uttorale; Feeding; Diel cycle; Lagoons.
Ano: 1997
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0101-81751997000100005

Ecological aspects of the surf-zone ichthyofauna of Itamambuca Beach, Ubatuba, SP
Provedor de dados: 49
Autores: Gondolo,Guilherme Fernandez; Mattox,George Mendes Taliaferro; Cunningham,Patricia Teresa Monteiro.
Sandy beaches are among the most extensive environments in Brazil and are generally threatened by disorderly urban growth due to their location along the coast, where human populations tend to concentrate. This is especially true in southeastern Brazil, where the largest urban areas are located. Thus, better knowledge regarding these natural resources is of considerable importance. The surf zone of sandy beaches is inhabited by a number of fish species, including juveniles seeking both food and shelter from predators. An ecological survey was conducted in the surf zone of Itamambuca beach in the city of Ubatuba, São Paulo State, Brazil, in order to evaluate the composition, structure and dynamics of the fish fauna using community descriptors. Diurnal and...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Marine fish; Sandy beach; Community; West Atlantic; Seasonal; Diel cycle.
Ano: 2011
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1676-06032011000200019