19 resultados para Roberto Piva
Resumo:
La presente lista constituye un nuevo aporte a la información de los peces de agua dulce de la Argentina (López et al., 1981, 1982, 1986 y 1989). Por razones de economía de espacio, hemos variado el esquema seguido en las anteriores, no mencionamos los resúmenes de las diferentes reuniones, ni las especies citadas en el texto de los trabajos incluidos. Por otra parte, no consideramos las contribuciones de nuestros colegas uruguayos (con excepción de aquellas referidas a cuerpos de agua compartidos), ya que temimos caer en olvidos involuntarios que, con el tiempo, se transformen en situaciones enojosas. (PDF tiene 15 paginas.)
Resumo:
La presente lista constituye el tercer suplemento a las bibliografías de los peces de Agua Dulce de la Argentina y Uruguay (López et al., 1981, 1982, 1986). Los criterios que sustentan la inclusión de los trabajos son los señalados en 1981. Se incluyen en este trabajo los artículos posteriores a 1986 y los que han pasado inadvertidos en las anteriores. Se mencionan las especies citadas, salvo cuando figuran en el título del trabajo o su número es excesivo. (PDF tiene 36 paginas.)
Resumo:
Four species of Characiformes and five species of Siluriformes are recorded from ten new argentine localities. New distributional data are discussed. Relevant morphological measurements and some comments are added.
Resumo:
Commercial trawling on the Atlantic slope areas off Brazil intensified in the late 1990’s owing to the expansion of coastal trawling areas and the operations of a chartered foreign fleet. Between 2000 and 2003, 59 fishing trips conducted by 10 chartered trawlers were intensely monitored by observers and satellite vessel monitoring systems, totaling 9,069 tows and 30,085.2 trawling hours. Fishing operations occurred in northern, northeastern, southeastern, and southern sectors of the Brazilian coast in 60–1,173 m depths. Total retained and processed catch were 8,074.6 t and 6,479.8 t, respectively. Argentine hake, Merluccius hubbsi; and Argentine shortfin squid, Illex argentinus, were the primary species taken contributing to 41.1% and 28.6% of the overall catch, respectively. The silver John dory, Zenopsis conchifera; monkfish, Lophius gastrophysus; Brazilian codling, Urophycis mystacea; and the black grouper, Epinephelus nigritus, composed 23% of total processed catch, and the remaining 7.2% was composed of deep-sea shrimps (family Aristeidae) and other teleosts and elasmobranches. The occupation of slope areas included an early exploratory phase, followed by directed phases of the upper slope (300–500 m), aiming principally at the Argentine hake, and the lower slope (>700 m), targeting valuable concentrations of deep-sea aristeid shrimps. The role of chartering for slope trawling development was critically addressed. We conclude that chartered vessels were efficient explorers and were particularly important in areas not available to the technologically limited national fleet. Because the charters were market-oriented and had elevated profit demands, however, those vessels quickly turned from exploration to exploitation and competed with national trawlers in shallower areas and produced significant impacts on Brazil’s modest deep-sea resources.