Browsing by Author "Espinach Ros, A."

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    El dorado, Salminus maxillosus (Pisces, Characiformes) en el Río de la Plata y Río Uruguay inferior
    (Mar del Plata: Instituto Nacional de Investigación y Desarrollo Pesquero (INIDEP), 1986) Sverlij, S.B.; Espinach Ros, A.
    Catch per unit effort (CPUE), lenght distribution, age, growth, reproduction, migrations and feeding were studies through samples collected with longlines and a gang of gill-nets of several mesh size. CPUE data showed a progressive decrease of the relative abundance in the Río de la Plata, during the study period. Age was studied from scales. Back-calculations of growth revealed the pressence of Lee's phenomenon. Means lenghts at age were greater in females. No significant difference was found in lenght-weight regressions from both sexes and sampling areas. Only young individuals from 1 to 6 years were caught. None of the fish studied had ripening gonads. Extensive migrations were recorded both in the Paraná and Uruguay rivers. Stomach contents analysis confirmed the ichthyoplagous habits of the species.
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    Growth of Argentine silverside (Odontesthes bonariensis) stocked at low densities in two oligohaline shallow lakes (Buenos Aires province, Argentina)
    (Mar del Plata : Instituto Nacional de Investigación y Desarrollo Pesquero (INIDEP), 2006) Espinach Ros, A.; Dománico, A.
    Argentine silversides (Odontesthes bonariensis) stocked as fry (45 days old) at low densities in two oligohaline Pampasic shallow lakes (Buenos Aires province, Argentina) grew to legal harvest size (250 mm, total length) in one year, and averaged 403 mm in length and 500 g in weight after 25 months.