Consulta: creatorFacets:"Acha, E.M."
Registros recuperados: 5
Data/hora: 11/06/2024 09:00:07

The Invasive Rapa Whelk Rapana venosa (Valenciennes 1846): Status and potential ecological impacts in the Rio de la Plata estuary, Argentina-Uruguay
Provedor de dados: 20
Autores: Giberto, D.A.; Bremec, C.; Schejter, L.; Schiariti, A.; Mianzan, H.W.; Acha, E.M.
Recent range extensions of the invasive rapa whelk Rapana venosa, biological data of the population and possible ecological impacts on the food webs of the Rio de la Plata estuary are presented. A total of 41 rapa whelks and 21 egg capsules were collected between February 2004 and March 2006. Specimens were found all over the mixohaline waters of the estuary, with records off Montevideo, Samborombon Bay and off Punta Rasa. Specimens ranged between 28 and 120 mm shell length. Almost all R. venosa presented epibionts all over the shell, suggesting an exposed lifestyle. Egg-masses were attached to specimens of R. venosa, debris and plastic garbage. The spatial distribution of R. venosa within the estuary was coupled with the spatial distribution of Mactra...
Tipo: Journal Contribution
Palavras-chave: Estuaries; Introduced species; Predators; Food webs; Estuaries; Predators; Food webs; Http://aims.fao.org/aos/agrovoc/c_2673; Http://aims.fao.org/aos/agrovoc/c_6163; Http://aims.fao.org/aos/agrovoc/c_10973.
Ano: 2006
URL: http://hdl.handle.net/1834/1572

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

Estrategia reproductiva de la saraca, Brazilian menhaden, Brevoortia aurea (Pisces: Clupeidae), en el estuario del Río de la Plata
Provedor de dados: 20
Autores: Acha, E.M.
The Brazilian menhaden, Brevoortia aurea, is the only species of genus Brevoortia in South American Atlantic waters, being abundant in the Rio de la Plata estuary.  The temporal and spatial reproductive pattern of this menhaden was analyzed in relation to the major hydrographic features of the region, and the reproductive biology was studied by using histological analysis of ovaries. B.aurea is a multiple spawner with indeterminate annual fecundity. Daily spawning activity was mostly in the afternoon (15:00 - 16:00),based on the incidence of females with both hydrated oocytes and postovulatory follicles. Spawning frequency, determined using the percentage of females with postovulatory follicles, was about 12.  during November.  At this frequency, each...
Tipo: Theses and Dissertations
Palavras-chave: Reproduction; Fecundity; Ovaries; Fish larvae; Eggs; Life history; Brackishwater fish; Spawning grounds; Spawning seasons; Estuaries; Estuaries; Ovaries; Eggs; Life history; Spawning grounds; Reproduction; Fecundity; Fish larvae; Http://aims.fao.org/aos/agrovoc/c_2673; Http://aims.fao.org/aos/agrovoc/c_5456; Http://aims.fao.org/aos/agrovoc/c_2502; Http://aims.fao.org/aos/agrovoc/c_12170; Http://aims.fao.org/aos/agrovoc/c_7277; Http://aims.fao.org/aos/agrovoc/c_6507; Http://aims.fao.org/aos/agrovoc/c_15725; Http://aims.fao.org/aos/agrovoc/c_2924.
Ano: 1999
URL: http://hdl.handle.net/1834/1458

Aspectos reproductivos de las principales especies de peces en la Zona Comun de Pesca Argentino-Uruguaya y en El Rincón. Noviembre, 1994
Provedor de dados: 20
Autores: Macchi, G.J.; Acha, E.M.
The maturity stages of the main commercial coastal fishes caught during the cruise H-13/94 are macroscopically analyzed, focusing this study on the white croaker Micropogonias furnieri and the striped weakfish Cynoscion striatus. Samples were obtained in the Argentine-Uruguayan Common Fishing Zone (AUCFZ) and El Rincón (Buenos Aires Prov., Argentina) during November 1994.
Tipo: Journal Contribution
Palavras-chave: Marine fish; Reproduction; Sexual maturity; Environmental conditions; Coastal waters; Reproduction; Sexual maturity; Environmental conditions; Coastal waters; Http://aims.fao.org/aos/agrovoc/c_6507; Http://aims.fao.org/aos/agrovoc/c_7016; Http://aims.fao.org/aos/agrovoc/c_32980; Http://aims.fao.org/aos/agrovoc/c_25205.
Ano: 1998
URL: http://hdl.handle.net/1834/2473

Caracterización de la zona de 'El Rincón' (provincia de Buenos Aires) como área de reproducción de peces costeros
Provedor de dados: 20
Autores: Acha, E.M.; Orduna, M.; Rodrigues, K.A.; Militelli, M.I.; Braverman, M.S.
In order to characterize the 'El Rincón' (Buenos Aires prov., Argentina) spawning ground, adult fishes were caught with a bottom trawl net and ichthyoplankton samples obtained with a Nackthai net. Salinity and temperature were measured with a CTD. Samples and measurements were performed during the RV Eduardo Holmberg EH-03/08 scientific cruise carried out in November 2008. The region is characterized by the presence of an oceanographic front formed by waters diluted by the discharges of the Negro and Colorado rivers, high salinity waters originated in the San Matías Gulf and intermediate salinity continental shelf waters. The eggs and/or larvae identified corresponded to Argentine anchovy, Brazilian flathead, Argentine seabass, red porgy, leatherjack,...
Tipo: Journal Contribution
Palavras-chave: Ichthyoplankton Marine fish Spawning grounds Coastal zone Reproduction Oceanography PSW; Argentina; Buenos Aires; El Rincon marine environment.
Ano: 2012
URL: http://hdl.handle.net/1834/4910