http://hdl.handle.net/1834/1358 Mon, 10 Jun 2013 15:21:31 GMT 2013-06-10T15:21:31Z http://hdl.handle.net/1834/2544 Title: Talla de primera madurez del abadejo (Genypterus blacodes) en el Atlántico Sudoccidental. Authors: Cordo, H.D.; Machinandiarena, L.; Macchi, G.J.; Villarino, M.F. Abstract: The length at first maturity (Lm50. ) and the maturity ogive are very important parameters in stock assessment. In this paper the ling Genypterus blacodes females Lm50. is estimated with frequencies of mature fish determined by microscope diagnosis of ovaries collected during the spawning season (SW Atlantic). The Lm50. of ling was estimated at 70.5 cm of total length (TL), which corresponds to an age of 4.5 years. The maturity process occurs between 63 and 78 cm TL (between 3.7 and 5.4 years). Tue, 01 Jan 2002 00:00:00 GMT http://hdl.handle.net/1834/2544 2002-01-01T00:00:00Z http://hdl.handle.net/1834/2533 Title: Síntesis de las evaluaciones y sugerencias de manejo efectuadas sobre el recurso merluza (Merluccius hubbsi) entre el año 1986 y mayo de 1997. Authors: Bezzi, S.I. Abstract: Hake (Merluccius hubbsi) stock assessments and management recommendations made as of 1986 for the Argentine Sea, are summarized. The surplus production models used allowed to diagnose an overdimensioned fleet and to establish that, as of 1983, population densities were lower than the optimum values. In 1990 it was mentioned that total landings exceeded the Maximum Sustainable Yield and that the fishing effort was above the optimum exploitation level. The Virtual Population Analysis was first applied in 1993 and, for the 1986-1991 period, a 25. increase in fishing mortality, significant reductions of total and reproductive biomasses and a first catch length of 25 cm were detected. Besides, proposals were made to enhance accuracy of future assessments. In 1994 stock assessment was updated and a significant reduction of the fishing effort was suggested. In 1995 two hake management units were defined and independent assessments initiated north and south of 41°S. The following year risk analysis was introduced and protection of patagonian hake nursery ground was suggested. In 1997 the ADAPT methodology was first applied and, considering the uncertainty of the information available, a risk analysis was performed. Conclusions were that north and south stocks were overfished, that total biomass was decreasing, that reproductive biomass was lower than the biologically acceptable level and that the fishery was sustained by a few year classes. Sat, 01 Jan 2000 00:00:00 GMT http://hdl.handle.net/1834/2533 2000-01-01T00:00:00Z http://hdl.handle.net/1834/2466 Title: Resultados de una campaña de evaluación de recursos demersales costeros de la Provincia de Buenos Aires y del litoral Uruguayo. Noviembre, 1994 Authors: Lasta, C.A. Abstract: The Coastal Project developed at the INIDEP (Mar del Plata,Argentina) offers an analysis on the operative modality of coastal assessment surveys, proposing an information process useful to standardize data collection and processes of future surveys. The efficiency of the evaluation of strata used until the year 1993 was analyzed and a new stratification is proposed. The aim was to define area-strata of importance for the main coastal species, using the traditional stratification of the coastal ecosystem and the mew methodology. The reason for redefining strata is that a decrease was been detected in the number of traditional species and an increment on the biomass of non-commercial species and,associated with it, the development of new explotation areas. The analysis of the physical environment of the coastal ecosystem includes aspects of the biology of such species and the distribution of reproductive concentrations, nursery and spawning areas, due in part to oceanographic structures like thermal, saline frontsand turbidity. The dynamics of coastal resources considering two different oceanographic areas with different types of fishing administration and different levels of fishing effort, are described. These two areas are: The Argentine Uruguayan Common Fishing Zone(AUCFZ), influenced by the Río de la Plata, and the area of El Rincón, of marine waters. In the area influenced by the estuary of the Río de la Plata the coastal fleets of Uruguay and Argentina carried out jointly commercial fishing activities; this area is administrated by the Administrating Commission of the Río de la Plata (ACRP)and the Mixed Technical Commission of the Marine Front(MTCMF) by means of the AUCFZ. In the area of El Rincón the only fishing fleet is Argentine and it is administrated by the Secretariat of Agriculture,Livestock, Fisheries and Food. Thu, 01 Jan 1998 00:00:00 GMT http://hdl.handle.net/1834/2466 1998-01-01T00:00:00Z http://hdl.handle.net/1834/2422 Title: Relación largo-peso y largo-edad de primera madurez sexual de la merluza Authors: Simonazzi, M. Abstract: Estimations were made on the basis of a subsample of 6,734 individuals of Merluccius hubbsi from the Argentine Sea south of 41°S. Length-weight relation potential regression parameters were a=0.00950863, 0.01093448 and 0.01096117b=2.90831652, 2.86558431 and 2.86583191 for males, females and total individuals, respectively. The Newton algorithm was used to minimize the residuals. Maturity ogives were estimated with the logistic model adjusted by no lineal minimum quadratic ordinates. Length at first maturity at 50 was 33.79 cm for males and 35.38 cm for females. Age at first maturity estimated with the same model adjusted to the time elapsed from birth to catching was 2.61 and 2.67 years for males and females, respectively. Good fitting in all regressions was obtained. Wed, 01 Jan 2003 00:00:00 GMT http://hdl.handle.net/1834/2422 2003-01-01T00:00:00Z