Revista de Investigación y Desarrollo Pesquero

Permanent URI for this community

https://marabierto.inidep.edu.ar/handle/inidep/9

Browse

Browsing Revista de Investigación y Desarrollo Pesquero by Subject "abundancia"

Now showing 1 - 3 of 3
  • No Thumbnail Available
    Item
    Distribución de huevos, larvas y prerreclutas de merluza (Merluccius hubbsi) en la Zona Común de Pesca Argentino-Uruguaya. Período 1999-2001
    (Mar del Plata : Instituto Nacional de Investigación y Desarrollo Pesquero (INIDEP), 2006) Machinandiarena, L.; Brown, Daniel R.; Ehrlich, Martín D.; Pájaro, Marcelo; Dorado, J.; Teso, V.
    Distribution and abundance of eggs, larvae and prerecruit stages of Merluccius hubbsi were evaluated to examine spawning, nursery and settlement areas in the Argentine-Uruguayan Common Fishing Zone during the 1999-2001 period. Larvae and prerecruit stages were more abundant at stations from 50 m to 100 m depth. The nursery area would extend from the 50 m isobath south of 37° S to the 200 m isobath northward where the shelf becomes narrower. In the whole sampling area small size prerecruits were caught; therefore, the whole zone should be considered as a potential settlement area.
  • No Thumbnail Available
    Item
    Distribución y abundancia de cápsulas de huevo y aspectos del desarrollo embrionario de las rayas Bathyraja brachyurops y Bathyraja macloviana en la plataforma bonaerense
    (Instituto Nacional de Investigación y Desarrollo Pesquero, 2016) Vazquez, Diego M.; Gabbanelli, Valeria; Díaz de Astarloa, Juan Martín; Mabragaña, Ezequiel
    In this work the distribution and abundance of egg cases of skates Bathyraja brachyurops and B. macloviana on the Buenos Aires continental shelf and the Mar del Plata submarine canyon are analyzed and stages of embryonic development described. Although distribution, similar for both species, was registered south of 37° S at 84-215 m depth, some cases of B. macloviana were found down to 1,395 m. The highest abundance of B. brachyurops was recorded between 97-145 m and 251 m and that of B. macloviana at 94-105 m. Results indicate similar oviposition areas that coincide with the Argentine break front and the Patagonian scallop banks. Cases with embryos in different stages of development were collected. The anatomical structures, similar for both species in the first stages, showed differences in spinulation and pigmentation in the final ones. In both species early stages of development were found between July and September. The different stages observed in B. brachyurops embryos in July suggest oviposition at different times of the year. Those of B. macloviana found in the same stage in different seasons and in different stages in the same season suggest a similar oviposition pattern.
  • No Thumbnail Available
    Item
    Influencia de las interacciones con el factor Año en los índices anuales de abundancia obtenidos por modelos lineales generales utilizando datos de Captura por Unidad de Esfuerzo
    (Mar del Plata : Instituto Nacional de Investigación y Desarrollo Pesquero (INIDEP), 2006) Hernández, Daniel R.; Perrotta, Ricardo G.
    The problem in the definition of a relative annual abundance index using a General Linear Model is posed. The possible factors generating changes in the catch per unit effort (CPUE) are discussed and the parameterization of the model is analyzed, in particular the Sigma-restrictive parameterization. This report considers the problem caused by the presence of interactions of first order that include the factor Year in the model. It has been mathematically demonstrated that in the presence of these interactions, the index series is not proportional to the abundance annual mean of the resource. An approach of practical order to evaluate the possible effect of the interactions that include the factor Year in the index is considered using the percentage of explained variance of the model with and without these interactions. Some methodological rules are also defined to attenuate several problems generated by the mentioned interactions: (1) evaluating if type of fleet, included as categories of the factor Ship, has experienced modifications throughout the period of study that could have generated changes in the efficiency of fishing units; (2) allowing for the possibility of working with indexes pondered by Area; (3) using the most convenient categorization for the factor Month (month, bimonthly, quarterly, fishery season, etc.), considering the seasonal distribution of the resource and the activity of the fleet, as well as the limitations generated by the presence of empty cells in the design. Two application examples are presented