Consulta: creatorFacets:"Sánchez, R.P."
Registros recuperados: 12
Data/hora: 13/06/2024 02:52:41

Ichthyoplankton composition, distribution and abundance on the southern patagonian shelf and adjacent waters.
Provedor de dados: 20
Autores: Ehrlich, M.D.; Sánchez, R.P.; de Ciechomski, J.D.; Machinandiarena, L.; Pájaro, M.
This paper reviews the information on pelagic and demersal fish eggs and larvae, describing the distribution and seasonality of different species and their arrangement in icthyoplankton assemblages in the Southern patagonian waters. It also reports on 11 surveys conducted by INIDEP during 1992-1995. A total of 488 ichthyoplankton samples were analyzed. Fish eggs have been recognized in 47.  of all ichthyoplankton samples. They belong to three species: Coelorhynchus fasciatus, Macrourus whitsoni and Micromesistius australis. Fish larvae of 23 species and 17 families have been identified in 96.  of all samples analyzed. Spawning of most species begins in autumn, and progresses through winter, when the southern blue whiting and grenadier fish contribute to...
Tipo: Journal Contribution
Palavras-chave: Ichthyoplankton; Fish larvae; Fish eggs; Seasonal distribution; Abundance; Fish larvae; Http://aims.fao.org/aos/agrovoc/c_2924.
Ano: 1999
URL: http://hdl.handle.net/1834/2574

Consideraciones sobre el crecimiento de la caballa (Scomber japonicus marplatensis)durante su primer año de vida
Provedor de dados: 20
Autores: Sánchez, R.P.
Through the analysis of the morphological changes ocurring in the process of growth, it was possible to identify three stages (primary juvenile: 25-75 mm; secondary juvenile: 76-160 mm; and juvenile preadult: 161-250 mm)during the first year of the species life. Regression equations for the different relations studied: body weight/body lenght, body surface/body lenght, body surface/body weight, and metabolic rate/body lenght, have been calculated for each stage. The variation of the number of gill rakers, mean distance between adjacent rakers and mean values of gill rakers lenght in reference to body growth was studied, and the relation between filtering area and body length was established.
Tipo: Journal Contribution
Palavras-chave: Length-weight relationships; Condition factor; Gills; Juveniles; Mackerel fisheries; Gills; Http://aims.fao.org/aos/agrovoc/c_3262.
Ano: 1982
URL: http://hdl.handle.net/1834/2047

Estudio sobre el crecimiento en peso y factor de condición en larvas de anchoíta, Engraulis anchoita Hubbs &amp; Marini. Variaciones regionales, estacionales y anuales
Provedor de dados: 20
Autores: de Ciechomski, J.D.; Sánchez, R.P.; Alespeiti, G.; Regidor, H.
The equation log W=a+bL (where W=dry weight in ug, and L=total length in mm)was used to describe the growth in weight of larval anchovy collected in two areas of the Argentine sea, sampled in different months and several years. Regression lines were compared by covariance analysis applied to two size groups, namely larvae less and over 10 mm total length, as an evident break in the slopes indicated the existence of a chenge of rythm in the trajectory of larval growth in length. Significant differences between the slopes of the growth lines were observed within the smaller size group. No regional or yearly differences could be established fo larvae larger than 10 mm.
Tipo: Journal Contribution
Palavras-chave: Length-weight relationships; Fish larvae; Condition factor; Fish larvae; Http://aims.fao.org/aos/agrovoc/c_2924.
Ano: 1986
URL: http://hdl.handle.net/1834/2023

Estudios sobre reproducción y fecundidad de la polaca (Micromesistius australis Norma 1937)en el Mar Argentino
Provedor de dados: 20
Autores: Sánchez, R.P.; de Ciechomski, J.D.; Acha, E.M.
An analysis is presented of reproduction aspects of Argentine Sea blue whiting. The species spawns in the study area mostly during August and September, although some spawners have been detected even in November. Total length at 50-per-cent maturity was 35,4 cm for the males and 38.0 for the females. Significant differences between the length of maturity for individuals of the continental shelf compared to those of the slope, have been obtained. The southern blue whiting is a discontinuous spawner, showing one annual reproduction peak. Fecundity was investigated on the basis of samples collected in 1978 by the RV"Walther Herwig" and "Shinkai Maru". A significant positive correlation was also observed at relating oocyte dry weight and gonad factor, whereas...
Tipo: Journal Contribution
Palavras-chave: Reproduction; Fecundity; Sexual maturity; Stock assessment; Stock assessment; Reproduction; Fecundity; Sexual maturity; Http://aims.fao.org/aos/agrovoc/c_24251; Http://aims.fao.org/aos/agrovoc/c_6507; Http://aims.fao.org/aos/agrovoc/c_15725; Http://aims.fao.org/aos/agrovoc/c_7016.
Ano: 1986
URL: http://hdl.handle.net/1834/2028

A drift study of vertical distribution and mortality of Engraulis anchoita eggs and larvae.
Provedor de dados: 20
Autores: Sánchez, R.P.; de Ciechomski, J.D.; Lasta, C.A.; Guerrero, R.A.
Lagrangian changes in distribution and survival within an anchovy egg and larvae patch were studied by means of multiple opening/closing sampling following a free drifting buoy. The buoy was equipped with a radar reflector and flashing light, and it was connected to a current cross drogue floating at 15 m depth, which corresponded to the main egg and larvae concentration within the patch. The drifter was launched on the Buenos Aires continental shelf, off Necochea during the spring spawning peak of 1983. Three discrete depths (within, below and above the thermocline)were repeatedly sampled close to the drogue with a Motoda sampler. Egg and larval abundances in the vicinity of the drogue were monitored at 3/4 hour intervals for a period of three days. Each...
Tipo: Journal Contribution
Palavras-chave: Fish larvae; Fish eggs; Vertical migrations; Feeding; Environmental effects; Ichthyoplankton surveys; Vertical distribution; Survival; Abundance; Drifting data buoys; Fishery surveys; Feeding; Fish larvae; Survival; Http://aims.fao.org/aos/agrovoc/c_2838; Http://aims.fao.org/aos/agrovoc/c_2924; Http://aims.fao.org/aos/agrovoc/c_7538.
Ano: 1999
URL: http://hdl.handle.net/1834/1871

Evaluación de la biomasa de adultos desovantes, distribución vertical y variación cuantitativa de la intensidad de los desoves de la anchoíta (Engraulis anchoita) durante la primavera de 1982
Provedor de dados: 20
Autores: de Ciechomski, J.D.; Sánchez, R.P.; Lasta, C.A.
Ichthyoplankton was sampled in 9 exploratory cruises in the sea off Buenos Aires province (Argentina), Uruguay and Brazil, during the spawning peak of the anchovy in spring-early summer and mid-autumn. The most abundant speices in the ichthyoplankton was Engraulis anchoita, representing 88. of the eggs and 76. of the larvae collected in all the cruises. These percentages vary boath regionally and seasonally; as regards eggs, the lowest percentage (10. ) was found in January. The distribution of anchovy eggs and larvae, covered almost entirely the surveyed area, with the exception of hte region influenced by the River Plate estuary. Minimum salinity tolerance for the species eggs was 23.5o/oo. The eastern limit of the distribution of anchovy eggs, extends...
Tipo: Journal Contribution
Palavras-chave: Vertical distribution; Fish eggs; Spawning populations.
Ano: 1986
URL: http://hdl.handle.net/1834/2040

Patrones de distribución espacio-temporal de los estadíos embrionarios y larvales de la anchoíta (Engraulis anchoita Hubbs &amp; Marini) a micro y macro-escala. Su relación con la supervivencia
Provedor de dados: 20
Autores: Sánchez, R.P.
This dissertation is focused on the study of implications of spatial patterns on survival of eggs and larvae and subsequent recruitment of the SW Atlantic anchovy, Engraulis anchoita. The study of distribution patterns is encompassed within the conceptual framework of the analysis of reproductive strategies of marine bony fish, as adaptations that enable them to cope with and actively exploit environmental variability, regulating their abundance and avoiding extinction. The SW Atlantic anchovy, is ideally suitable for studies on reproductive biology and recruitment on a comparative basis. Its spawning and nursery grounds are located in very diverse ecosystems. This variety refers to their physico-chemical properties, carrying capacity, the influence of...
Tipo: Theses and Dissertations
Palavras-chave: Fish eggs; Fish larvae; Recruitment; Ichthyoplankton; Biomass; Reproduction; Developmental stages; Mortality; Stock assessment; Environmental conditions; Biomass; Developmental stages; Stock assessment; Fish larvae; Reproduction; Mortality; Environmental conditions; Http://aims.fao.org/aos/agrovoc/c_926; Http://aims.fao.org/aos/agrovoc/c_2230; Http://aims.fao.org/aos/agrovoc/c_24251; Http://aims.fao.org/aos/agrovoc/c_2924; Http://aims.fao.org/aos/agrovoc/c_6507; Http://aims.fao.org/aos/agrovoc/c_4945; Http://aims.fao.org/aos/agrovoc/c_32980.
Ano: 1995
URL: http://hdl.handle.net/1834/1491

Exploraciones oceanográficas y pesqueras en el Mar Argentino y la región adyacente del Atlántico Sudoccidental (años 1874-1993)
Provedor de dados: 20
Autores: Angelescu, V.A.; Sánchez, R.P.
A detailed analysis is presented of the main contributions both local and international to the fields of oceanography and fishery sciences resulting from exploratory cruises carried out on the continental shelf off Argentina and the adjacent oceanic basin of SW Atlantic over the last 100 years. The end of the 19th century is chosen as starting point for this analysis as it marks the beginning of active marine research by Argentine scientists and an accumulation of information on Antarctic and Subantarctic marine organisms in foreign journals. Mention is also made to previous contributions derived from the classic expeditions and global circumnavigation voyages during the 18th and 19th centuries. Although the aims of those were not always strictly...
Tipo: Book Section
Palavras-chave: Oceanography; Oceanographic surveys; Fishery oceanography; Fishery surveys; Historical account; International cooperation; Research vessels; Fishery oceanography; Research vessels; Oceanography; International cooperation; Http://aims.fao.org/aos/agrovoc/c_2938; Http://aims.fao.org/aos/agrovoc/c_6516; Http://aims.fao.org/aos/agrovoc/c_12889; Http://aims.fao.org/aos/agrovoc/c_16378.
Ano: 1997
URL: http://hdl.handle.net/1834/1705

Estimación de la biomasa de adultos desovantes de la anchoíta (Engraulis anchoita)en el área costera bonaerense durante la primavera de 1981 y análisis comparativo de los recuentos de ictioplancton con redes de diferentes mallas
Provedor de dados: 20
Autores: Sánchez, R.P.; de Ciechomski, J.D.
A bongo sampler fifted with nets of two different mesh sizes, 330 and 505 u. was used to collected 137 ichthyoplankton samples in the coastal areas off Buenos Aires Province in October, 1981. The efficiency of the two meshes for catching anchovy eggs and larvae and total ichthyoplankton was examined. The statistical analysis of the samples shows that there are no significant differences between the numbers of anchovy and total eggs collected by the different meshes. As regards anchovy and total larvae the finer mesh showed as significantly higher catching efficiency. The results of this partial estimate do not suggest that a major revision of the total assessment of the complete stock is necessary.
Tipo: Journal Contribution
Palavras-chave: Stock assessment; Fish eggs; Stock assessment; Http://aims.fao.org/aos/agrovoc/c_24251.
Ano: 1984
URL: http://hdl.handle.net/1834/2044

Larval and juvenile growth of two Patagonian small pelagic fishes: Engraulis anchoita and Sprattus fuegensis
Provedor de dados: 20
Autores: Brown, D.R.; Sánchez, R.P.
Patagonian anchovy (Engraulis anchoita) and sprat (Sprattus fuegensis) constitute the two most important pelagic resources of the Argentine Patagonian shelf (SW Atlantic). Age and growth parameters of larvae and juveniles of both species were determined analyzing otoliths daily increments. A total of 404 anchovies (4.1-33 mm SL) and 157 sprats (5-41 mm SL) were analyzed. The Laird-Gompertz growth model was fitted to the length-at-age data of anchovies: L(t) = 4.2 exp (2.28 (1-(-0.034 t))). The parameters of the model were: L: 41.06 mm; the inflection point: 15.11 mm and 27 days; and the maximum growth rate: 0.51 mm day-1. The length-at-age data of sprat larvae and juveniles were represented in two linear models: L(t) = 0.32 t + 7.6; and L(t) = 0.22 t +...
Tipo: Journal Contribution
Palavras-chave: Fish larvae juveniles growth rate otoliths pelagic fish Atlántico Sudoccidental; Argentina daily increments marine environment Engraulis anchoita Sprattus fuegensis.
Ano: 2010
URL: http://hdl.handle.net/1834/4222

Estudios sobre las variaciones espacio-temporales en los patrones de distribución de embriones y larvas de la anchoíta (Engraulis anchoita), en relación con la estimación de su intensidad reproductiva
Provedor de dados: 20
Autores: Sánchez, R.P.
Ichthyoplankton samples were collected during an exploratory cruise carried out by the RV Dr.Holmberg during the spring spawning peak of 1981 in the sea-shelf off Buenos Aires province (Argentina). The cruise was designed to carry out population studies in a restricted area of intense reproduction activity, in order to gather information on the time-space patterns of distribution of the eggs and larvae of the species.
Tipo: Journal Contribution
Palavras-chave: Fish larvae; Mortality; Growth curves; Controlled conditions; Fish eggs; Fish larvae; Mortality; Http://aims.fao.org/aos/agrovoc/c_2924; Http://aims.fao.org/aos/agrovoc/c_4945.
Ano: 1986
URL: http://hdl.handle.net/1834/2031

Fecundidad y frecuencia reproductiva de las poblaciones bonaerense y patagónica de anchoíta Argentina Engraulis anchoita.
Provedor de dados: 20
Autores: Pájaro, M.; Macchi, G.J.; Sánchez, R.P.
Fecundity and spawning frequency were estimated in the northern(off Buenos Aires Province)and southern (patagonian)argentine anchovy Engraulis anchoita populations in 1993, during the peak of the spawning season. Relative fecundity, expressed as eggs per ovary-free weight was 574±21 (CI 95. ) and 605±49 (CI 95. ) in the northern and southern populations. The difference was not statistically significant between stocks (P0.13). Relative fecundity was higher in anchovies larger than 130 mm. The mean batch fecundity for the northern and southern populations was 13675±856 (CI 95. ) and21677±2.753 (CI 95. ) respectively. Batch fecundity (F)expressed as alinear function of ovary-free weight (W)was: F=-1310+649 * W(northern), F=-5935+786 * W (southern). The daily...
Tipo: Journal Contribution
Palavras-chave: Ovaries; Fecundity; Spawning populations; Fish eggs; Spawning seasons; Ovaries; Fecundity; Http://aims.fao.org/aos/agrovoc/c_5456; Http://aims.fao.org/aos/agrovoc/c_15725.
Ano: 1997
URL: http://hdl.handle.net/1834/1935