|
|
|
|
|
Zavatteri, A.; Abachian, V.E.; Giussi, A.R.; Di Leva, I.V.. |
Estimate of age, growth and natural mortality of longtail hake (Macruronus magellanicus) in the Southwest Atlantic Ocean during summer 2010. Longtail hake (Macurornus magellanicus) total length (TL) and weight (W) growth parameters were estimated and age structure and natural instantaneous mortality coefficient (M) analyzed. Data were obtained within the framework of the Instituto Nacional de Investigación y Desarrollo Pesquero (INIDEP) “Observers on Board of Commercial Vessels” Subprogramme. The information, derived from the area comprised between 46° S-54° S, was collected during the February-April 2010 period. Sagittae otoliths reading of 5,034 individuals (2,429 males and 2,605 females) between 28-99 cm TL was performed. The maximum ages observed in... |
Tipo: Journal Contribution |
Palavras-chave: Age determination; Growth; Natural mortality. |
Ano: 2013 |
URL: http://hdl.handle.net/1834/5504 |
| |
|
|
Wöhler, O.C.; Giussi, A.R.; Hansen, J.E.. |
Sequential population analysis on Long Tail Hake (Macruronus magellanicus)from the Southwest Atlantic. Years 1985-1995. VPA on the Long Tail Hake (Macruronus magellanicus), based on data covering the years 1985 up to 1995, was performed to assess the current state of the stock. Simulation trials, inducing uncertainty about both the natural mortality rate and recruitment were also accomplished, to evaluate the risk of overfishing which is associated to different fishing alternatives, always under the assumption of a single and closed Long Tail Hake population. CPUE data were not appropriate for tunning, so the traditional VPA has been applied. During the period of study, stock biomass and spawning stock biomass showed an increased trend. Long and short-term... |
Tipo: Journal Contribution |
Palavras-chave: Stock assessment; Fishery management; Catch/effort; Fishing mortality; Overfishing; Biomass; Sexual maturity; Stock assessment; Fishery management; Biomass; Overfishing; Sexual maturity; Http://aims.fao.org/aos/agrovoc/c_24251; Http://aims.fao.org/aos/agrovoc/c_24026; Http://aims.fao.org/aos/agrovoc/c_926; Http://aims.fao.org/aos/agrovoc/c_34068; Http://aims.fao.org/aos/agrovoc/c_7016. |
Ano: 1999 |
URL: http://hdl.handle.net/1834/1875 |
| |
|
|
Giussi, A.R.; Sánchez, F.; Wohler, O.C.; Bernardele, J.C.. |
Several grenadier species distribute in the SW Atlantic Ocean. Macrourus carinatus and Caelorinchus fasciatus are more frequently identified in commercial catches and during research cruises. Those benthopelagic fishes, related to subantarctic waters, inhabit at depths beyond 200 m and in high seas, between 36º S-59º S. During the surveys carried out on board of Argentinean research vessels, M. carinatus was present in 4% of the trawls performed. The highest densities (>17 t nm-2), obtained between 360-380 m depth, at 39º S, decreased significantly southwards. C. fasciatus was caught in 6% of the total trawls and the highest densities (15-35 t nm-2) were found at depths beyond 200 m, south of 52º S. Due to the difficulty encountered to identify them, in... |
Tipo: Journal Contribution |
Palavras-chave: Commercial fishing bottom trawling demersal fisheries catch statistics Atlántico Sudoccidental; Argentina marine environment. |
Ano: 2010 |
URL: http://hdl.handle.net/1834/4220 |
| |
|
|
Gorini, F.L.; Abachian, V.E.; Giussi, A.R.. |
Southern hake (Merluccius australis) age and growth were estimated using sagittae otoliths obtained in research cruises and observers programs in the Argentine Sea (SW Atlantic). The only annual growth ring observed, formed by two bands, one hyaline and another opaque, corresponded to winter and summer growth, respectively. According to the analysis of otoliths edge, birthday was established on 1st July. Within the age range observed, that comprised 3-18 year old specimens, age groups 7, 8 and 9 were the most frequently identified in both sexes. Growth parameters estimates showed significant differences between them. |
Tipo: Journal Contribution |
Palavras-chave: Age determination Age groups Growth rings Otoliths Merluccius australis Atlántico Sudoccidental; Argentina marine environment. |
Ano: 2010 |
URL: http://hdl.handle.net/1834/4223 |
| |
|
|
Jerez, B.; Hernández, D.R.; Giussi, A.R.; Malaspina, A.M.. |
To determine the existence of different population units of longtail hake (Macruronus magellanicus) of the Argentine Sea, the meristic and morphometric characters of 861 specimens from two different areas were studied measuring 24 body distances with the landmark methods. Besides, the relation among weight, width and thickness of 806 pairs of sagittae otoliths as a function of length and sex of individuals was analyzed. Using the General Linear Model, the Principal Component Analysis and the Multivariate Analysis of Variance the fitted morphometric variables, the meristic characters and their relation to the Area and Sex factors were assessed. The variability observed does not show any conclusive evidence about the existence of more than one stock in the... |
Tipo: Journal Contribution |
Palavras-chave: Stock identification; Meristic counts; Morphometry; Otoliths. |
Ano: 2013 |
URL: http://hdl.handle.net/1834/5490 |
| |
|
| |
|
|
Wöhler, O.C.; Giussi, A.R.; García de la Rosa, S.B.; Sánchez, M.F.; Hansen, J.E.; Cordo, H.D.; Alvarez Colombo, G.L.; Incorvaia, I.S.; Reta, R.; Abachián, V.E.. |
An assessment survey on the austral fish was carried out during the summer 1997 on both the shelf and slope off southern Argentina. The cruise covered 101,508 nm2 between 45° and 54° 30'S and depths between 50 and 400 m. The survey did not include the area controlled by the United Kingdom. Considering the total area as an undivided stratum, a random sampling was used to estimate demersal fish biomass and a delta distribution-based model to evaluate mean densities. Out of the forty five species caught 28 were bony fish and 17 elasmobranch. Four cephalopod mollusc species were also identified. A biomass of 3.2 million tons (CI(95o/o): 1.90 - 6.06 millions) proved that longtail hake was the most abundant resource within the region followed by common hake... |
Tipo: Journal Contribution |
Palavras-chave: Demersal fisheries; Fishery surveys; Biomass; Population structure; Feeding; Parasitism; Environmental conditions. |
Ano: 1999 |
URL: http://hdl.handle.net/1834/5782 |
| |
|
|
Wöhler, O.C.; Hansen, J.E.; Giussi, A.R.; Cordo, H.D.. |
Period 1985-2001. A stock assessment of Patagonian hoki of the Southwest Atlantic was carried out by using data from the years 1985-2001. A cohort analysis, fitted with some survey abundance indices was used in an adaptive conceptual framework. Simulation trials were performed to project the evolution of the fishery, to evaluate the risk of over-fish the stock under different exploitation levels, and to estimate Biologically Acceptable Catches (BAC). Both total biomass and spawning stock biomass showed increasing trends resulting from four strong year classes (1993, 1995, 1996 and 1998). Total biomass at the beginning of 2001 was estimated to be 2.5 million tons, and spawning stock biomass at the spawning time (August) was estimated to be around 1.28... |
Tipo: Journal Contribution |
Palavras-chave: Stock assessment; Fishery management; Biomass; Risks; Demersal fisheries; Stock assessment; Fishery management; Biomass; Demersal fisheries; Http://aims.fao.org/aos/agrovoc/c_24251; Http://aims.fao.org/aos/agrovoc/c_24026; Http://aims.fao.org/aos/agrovoc/c_926; Http://aims.fao.org/aos/agrovoc/c_2173. |
Ano: 2007 |
URL: http://hdl.handle.net/1834/2525 |
| |
|
|
|