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Registros recuperados: 54 | |
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Durieux, Eric; Meekan, Mark G.; Ponton, Dominique; Vigliola, Laurent. |
Six cohorts of the silver-stripe round herring Spratelloides gracilis, a fast-growing and short-lived tropical clupeid, were collected as juveniles and then as adults during austral summers from November to February in 1998–1999 and 1999–2000, using light traps in the Dampier Archipelago, Western Australia. Otolith analysis allowed backcalculation of size and growth rate at age to examine the relative influences of selective mortality and water temperature on early growth. Negative sizeselective mortality and growth-selective mortality between the juvenile and the adult stages was found only in the cohort that was the smallest and slowest growing in the period immediately following hatching. Selective mortality preferentially removed members of this cohort... |
Tipo: Text |
Palavras-chave: Environmental factors; Indo-Pacific region; Life-history traits; Otolith; Pelagic fishes; Size. |
Ano: 2009 |
URL: http://archimer.ifremer.fr/doc/00008/11940/8643.pdf |
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Dimeet, Joel. |
Une évaluation du gisement d'oursins du golfe du Morbihan a été réalisée en 2008.Six stations ont été échantillonnées : Stibiden, Roc'h Vihan, Port Blanc, Kerners, Hent tenn et Brannec, une station de plus que les années précédentes Pour les cinq stations communes à 2007 et 2008 l'augmentation de la population d'oursins est de 5 % en global et de 25% pour les individus commerciaux. Les densités totales varient entre 87 et 136 individus pour 100 m2 et les densités commerciales entre 56 et 87 oursins pour 100m2. La densité maximale d'oursins commerciaux a été observée à Port blanc. Les tailles des oursins s'échelonnent entre 22mm et 88mm. 63% des oursins échantillonnés avaient une taille supérieure à la taille de première commercialisation, soit 55mm. |
Tipo: Text |
Palavras-chave: Density; Size; Sampling; Survey; Gulf of Morbihan; Layer; Urchin; Densité; Taille; Évaluation; Échantillonnage; Golfe du Morbihan; Gisement; Oursin. |
Ano: 2008 |
URL: http://archimer.ifremer.fr/doc/2008/rapport-6775.pdf |
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Richard, Marion; Forget, Fabien; Mignucci, Alexandre; Mortreux, Serge; Le Gall, Patrik; Callier, Myriam; Weise, Am; Mckindsey, Cw; Bourjea, Jerome. |
Bivalve predation by seabream has been observed worldwide and is a major concern for bivalve farmers. Farmed bivalve-seabream interactions must be better understood to ensure the sustainability of bivalve aquaculture. The objectives of this study were to characterize gilthead seabream Sparus aurata presence in a bivalve farm in Prevost Lagoon (Mediterranean Sea) using acoustic telemetry and to evaluate monthly losses of mussels Mytilus galloprovincialis and oysters Crassostrea gigas due to seabream predation over an 18 mo period inside the farm and at an unprotected experimental platform. Large (281 to 499 mm TL) seabream were more commonly detected in the bivalve farm than were small (200 to 280 mm TL) seabream. In contrast to small seabream, 90% of large... |
Tipo: Text |
Palavras-chave: Shellfish culture; Sparus aurata; Size; Acoustic telemetry; Crassostrea gigas; Mytilus galloprovincialis; Oyster; Mussel. |
Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00663/77515/79299.pdf |
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Azema, Patrick; Maurouard, Elise; Lamy, Jean-baptiste; Degremont, Lionel. |
Mortality associated with ostreid herpesvirus 1 (OsHV-1) has significantly impacted Crassostrea gigas farmers all around the world. Although selective breeding programs to improve OsHV-1 resistance can significantly reduce the mortality rate below 20%, husbandry practices have also been one way to limit or decrease mortality. The main objectives of this study were to describe the influence of two husbandry practices on OsHV-1-induced mortality in C. gigas spat and how different family lines respond to husbandry practices to gain a better understanding of the potential benefits of breeding management as a tool to adapt to improved practices. The first analysis investigated the importance of the size of C. gigas when challenged with OsHV-1 for the first... |
Tipo: Text |
Palavras-chave: Mortality; Crassostrea gigas; Size; OsHV-1; Growing height. |
Ano: 2017 |
URL: http://archimer.ifremer.fr/doc/00366/47717/47758.pdf |
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Sauriau, P; Baud, Jean-pierre. |
Based on Coulter Counter data, a new method is proposed to study the influence of the polymorphous variability in size as well as in shape of the diatom species Skeletonema costatum on the physiological performances of the Manila clam Ruditapes philippinarum . Three conditions are required in order to convert volumetric data determined with the Coulter Counter into metric data, i.e. (1) stability of the pervalvar diameter of the diatom chains, (2) statistical independence between length and pervalvar diameter of the diatom chains, and (3) negligible level of coincident passages through the aperture orifice. Under these three conditions, the mean length (l) of a S. costatum chain can be related to the mean pervalvar diameter (d) of diatom chains and to the... |
Tipo: Text |
Palavras-chave: Bivalvia; Skeletonema costatum; Bacillariophyceae; Algae; Physiology; Biopolymorphism; Counters; Size; Size distribution; Feeding; Nutrition. |
Ano: 1991 |
URL: http://archimer.ifremer.fr/doc/1991/acte-1670.pdf |
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Simon, Victor; Elleboode, Romain; Mahe, Kelig; Legendre, Laurent; Ornelas-garcia, Patricia; Espinasa, Luis; Retaux, Sylvie. |
Background Life in the darkness of caves is accompanied, throughout phyla, by striking phenotypic changes including the loss or severe reduction in eyes and pigmentation. On the other hand, cave animals have undergone constructive changes, thought to be adaptive, to survive in this extreme environment. The present study addresses the question of the evolution of growth in caves, taking advantage of the comparison between the river-dwelling and the cave-dwelling morphs of the Mexican tetra, Astyanax mexicanus. Results A sclerochronology approach was undertaken to document the growth of the species in these two very distinct habitats. Scales from 158 wild Astyanax mexicanus specimens were analyzed from three caves (Pachón, Tinaja and Subterráneo) and two... |
Tipo: Text |
Palavras-chave: Cave; Fish; Size; Age; Scales; Growth; Food; Comparative biology; Life history traits. |
Ano: 2017 |
URL: http://archimer.ifremer.fr/doc/00412/52337/53124.pdf |
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Fleury, Pierre-gildas; Mingant, Christian; Castillo, A. |
In order to have a better understanding of recessing in great scallop, Pecten maximus and consequently the causes of mortality at reseeding, this study has monitored, at different seasons, the dispersion and recessing of different sizes of juveniles (about 15, 30 and 45 mm, called small, medium and large) after seeding. Moreover, the aim was to see when small spat (15 mm) could be seeded, and thus reduce the costs of intermediate culture. Three monitoring approaches were used together: (1) continual observations by remote video camera, of a defined area (less than 1 m2) containing 10 scallops from each size group; (2) daily monitoring of behaviour with divers along three bottom lines, with 20 × 1 m2 plots each and nine marked scallops per plot; and (3) the... |
Tipo: Text |
Palavras-chave: Behaviour; Great scallop (Pecten maximus); Season; Seeding; Size; Vitality of spat. |
Ano: 1996 |
URL: http://archimer.ifremer.fr/doc/00326/43752/43284.pdf |
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Martins, Irene; Colaco, Ana; Dando, Paul R; Martins, I; Desbruyeres, Daniel; Sarradin, Pierre-marie; Marques, J; Serrao Santos, R. |
Bathymodiolus azoricus is a mussel from vent fields in the south-west of the Azores Triple junction (Mid-Atlantic Ridge-MAR). Experimental evidence indicates that B. azoricus is a mixotrophic organism, which obtains energy from a dual endosymbiosis and filter-feeding. Yet the relative contribution of symbiosis and filter-feeding to B. azoricus nutrition is still unclear. To address this question, we developed and individual-based model which describes sulphide and methane uptake by endosymbionts, the energy gained through microbial oxidations, the transfer of energy from endosymbionts to B. azoricus, filter-feeding of particulate organic matter (POC) by B. azoricus and the energetic wastes of the mytilid with respiration. The model accounts for... |
Tipo: Text |
Palavras-chave: Carbon flux model; Organic matter; Size; Filter feeding; Endosymbiosis; Bathymodiolus azoricus. |
Ano: 2008 |
URL: https://archimer.ifremer.fr/doc/2008/publication-4541.pdf |
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Durieux, Eric; Farver, Thomas B.; Fitzgerald, Patrick S.; Eder, Kai J.; Ostrach, David J.. |
Acetylcholinesterase (AChE) activity is one of the most common biomarkers of neurotoxicity used in aquatic organisms. However, compared to its extensive use as biomarker, the effects of natural factors onAChE activity remain unclear especially in estuarine fishes. The aim of this study was to evaluate the effects of natural factors on AChE activity of striped bass (Morone saxatilis) juveniles. Brain AChE activity was measured in YOY (Young-Of-Year) individuals collected monthly from August 2007 to January 2008 at 12 different sites in the San Francisco Estuary system. The spatio-temporal variability of AChE was analyzed relative to water temperature and salinity as well as fish size. AChE activity was highly positively correlated with water temperature and... |
Tipo: Text |
Palavras-chave: Fish; Biomarker; Acetylcholinesterase; Brain; Temperature; Salinity; Size. |
Ano: 2011 |
URL: http://archimer.ifremer.fr/doc/00008/11939/8642.pdf |
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Degremont, Lionel. |
As with summer mortalities reported in France between 2001 and 2006, mortality caused by the Ostreid herpesvirus 1 (OsHV-1) in Crassostrea gigas affects mostly juveniles, although adults can also be impacted to a small extent. This could suggest that both mortalities have similar causes and that establishment of resistance, in particular to the Ostreid herpesvirus 1 (OsHV-1), depends on either the size or the age of oysters. The present study reports an investigation of both size and age using three cohorts produced during winter and three produced during summer. Each cohort contained oysters genetically selected to be resistant or susceptible to the summer mortality phenomenon, as well as unselected control oysters. Any abnormal mortality was recorded... |
Tipo: Text |
Palavras-chave: Mortality; Crassostrea gigas; Disease resistance; Size; Age; Ostreid herpesvirus. |
Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00157/26799/24909.pdf |
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Lorrain, A.; Clavier, J.; Thebault, J.; Tremblay-boyer, L.; Houlbreque, F.; Amice, E.; Le Goff, M.; Chauvaud, L.. |
Researchers often use metabolic measurements in the field over narrow time periods to estimate an organism's metabolism over large time scales. Here, we measured in situ respiration, calcification and excretion rates of the tropical gastropod Tectus niloticus L. through benthic chamber experiments. Our samples spanned a 21 h time frame and were taken during both the warm and cool seasons. We assessed diel and seasonal variability in metabolic rates, as well as the effect of individual size and the contribution of shell epi-and endobionts. Our results show that metabolic rates vary through time at both diel and seasonal scales, as measured fluxes for respiration and calcification were significantly higher at night during the warm season. This nocturnal... |
Tipo: Text |
Palavras-chave: Gastropod; Seasonal variations; Diel variations; Size; Carbon fluxes; CO2; CaCO3; New Caledonia. |
Ano: 2015 |
URL: https://archimer.ifremer.fr/doc/00256/36675/39633.pdf |
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Loskot, V.M.. |
Individual, sex, age, seasonal and geographic variation of size and plumage coloration of Lesser Whitethroat Sylvia curruca (Linnaeus, 1758) was studied on more than 1100 bird skins from all parts of its breeding range. The results of analysis of birds from the south-eastern part of the breeding range of the species support the validity of five light-coloured subspecies: halimodendri Sushkin, 1904, telengitica Sushkin, 1925, snigirewskii Stachanow, 1929, minula Hume, 1873, and margelanica Stolzmann, 1897. Their diagnoses and ranges are refined and supplemented. Numerous phenotypically intermediate birds from intergradation zones between the subspecies show that these five together with the two northern darkcoloured forms S. c. curruca and S. c. blythi... |
Tipo: Article / Letter to the editor |
Palavras-chave: Sylvia; Lesser Whitethroat; Species-limits; Intergradation; Subspecies; Nomenclature; Systematics; Intraspecific variation; Size; Plumage coloration; Distribution.; 42.83. |
Ano: 2005 |
URL: http://www.repository.naturalis.nl/record/210817 |
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Nordhagen, J.R.; Heuch, P.A.; Schram, T.A.. |
Salmon lice Lepeophtheirus salmonis (Krøyer, 1837) from farmed Atlantic salmon have been implicated in the drastic sea trout and salmon stock declines found in Ireland and Norway. Can salmon lice from farmed and wild fish be distinguished? The hypothesis has been advanced that the treatment of salmon infested with salmon lice with organophosphate pesticides has resulted in the evolution of early maturing, smaller female lice, which are favoured because they have the chance to reproduce before treatment. Salmon lice on wild fish have been reported to be larger and have more eggs in their egg strings (sacks) than lice on farmed fish. The question is whether the size differences between the lice are genetically fixed or an expression of phenotypic plasticity.... |
Tipo: Article / Letter to the editor |
Palavras-chave: Salmon lice; Origin; Size; Phenotypic plasticity. |
Ano: 2000 |
URL: http://www.repository.naturalis.nl/record/534287 |
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Registros recuperados: 54 | |
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