|
|
|
| Registros recuperados: 32 | |
|
|
| Perrotta, R.G.; Viñas, M.D.; Madirolas, A.; Reta, R.; Akselman, R.; Castro Machado, F.; Garciarena, A.D.; Macchi, G.J.; Moriondo Danovaro, P.; Llanos, V.; Urteaga, J.R.. |
| Between September 1st and 6th a research cruise was carried out in the Buenos Aires shelf area of "El Rincon" 39°40'-41°30'S, Argentine Sea SW Atlantic. The total area studied was 2,527.8 nautical mile2. Knowledge of the commercial fleet location at the time of the survey allowed to intensify sampling in a 'miniarea' of 52,8 nautical mile2. The acoustic assessment of chub mackerel (Scomber japonicus) biomass was 49,511.9 t, 94 of which corresponded to this last area. Fish samples coming from fishing trawls included only adult individuals of 240-460 mm total length (TL) and ages ranging 2-11 years. The limit age was estimated at 13 years and natural and total mortality rates at 0.23 and 0.54, respectively. Oceanographic conditions were those typical of the... |
| Tipo: Journal Contribution |
Palavras-chave: Population characteristics; Echo surveys; Mackerel fisheries; Fishery oceanography; Biomass; Environmental conditions; Fishery oceanography; Biomass; Environmental conditions; Http://aims.fao.org/aos/agrovoc/c_2938; Http://aims.fao.org/aos/agrovoc/c_926; Http://aims.fao.org/aos/agrovoc/c_32980. |
| Ano: 2003 |
URL: http://hdl.handle.net/1834/2418 |
| |
|
| |
|
|
| Hernández, D.R.; Perrotta, R.G.. |
| Pope's Cohorts Analysis was modified to extend its application to a wider range of natural mortality, M and fishing mortality, F rate values. The modified method maintains the simplicity of the one established by Pope and does not require to resolve any non lineal equation in each cohort reconstruction process. The relative errors obtained when estimating the number of individuals per age (maximum and mean in absolute value) showed acceptable levels within the five domains (M and F pairs of values) analyzed in this work. The new method can be adapted to a particular situation (M and F values range) simply solving an optimization problem (minimization of the maximum relative error absolute value) easily achieved using a calculation sheet or considering the... |
| Tipo: Journal Contribution |
Palavras-chave: Fishing mortality; Natural mortality; Stock assessment; Stock assessment; Http://aims.fao.org/aos/agrovoc/c_24251. |
| Ano: 2008 |
URL: http://hdl.handle.net/1834/3143 |
| |
|
| |
|
| |
|
| |
|
|
| Perrotta, R.G.. |
| Analyzed in this paper is the structure of the fleet applied to mackerel fishing based at Mar del Plata Port (38° LS); an attempt is also made at establishing the best system for measuring the fishing effort; the changes in catch capability (availability and vulnerability)are duly analyzed. Sampling vessels that allow greater data, particulary by in relation to the fishing effort, are available since the 1983/84 fishing season. |
| Tipo: Journal Contribution |
Palavras-chave: Catch/effort; Catchability; Fishing fleet. |
| Ano: 1988 |
URL: http://hdl.handle.net/1834/1959 |
| |
|
| |
|
| |
|
| |
|
|
| Lasta, C.A.; Carozza, C.R.; Suquelle, P.; Bremec, C.; Errazti, E.; Perrotta, R.G.; Cotrina, C.P.; Bertelo, C.; Boccanfuso, J.. |
| Whitemouth croaker Micropogonias furnieri fishery during three intensive fishing seasons in the outer area of the La Plata River (Argentina-Uruguay) is analyzed. Resource exploitation in the South Atlantic area shows a general retraction of the distribution range and an isolation of the La Plata River stock where most of the fishing effort concentrates. The species market evolution brought about, for Argentina and Uruguay, an important shift in its dynamics as of 1992, when the product insertion in Asiatic markets generated an important commercial attraction and a subsequent increase in the fishing effort by the argentine inshore coastal fleet. This caused a change in the fishery development in Argentina and the establishment, in winter, of a fleet... |
| Tipo: Journal Contribution |
Palavras-chave: Coastal fisheries; Fishery management; Catch/effort; Landing statistics; Marketing; Fishery management; Marketing; Coastal fisheries; Http://aims.fao.org/aos/agrovoc/c_24026; Http://aims.fao.org/aos/agrovoc/c_4620; Http://aims.fao.org/aos/agrovoc/c_1696. |
| Ano: 2000 |
URL: http://hdl.handle.net/1834/2540 |
| |
|
|
| Urteaga, J.R.; Perrotta, R.G.. |
| Argentine black drum distributes mainly in shallow waters associated to estuarine areas, particularly to Samborombon Bay where it may be detected throughout the year. Nevertheless, it can also be spotted more southwards (40°S) and at deeper waters. During summer, catches of the species in Samborombon Bay are practically negligible, probably due to movements towards shallow waters out of reach of the inshore commercial fleet. Landings increase in autumn and show peak values in winter, coinciding with the fishing season of whitemouth croaker, Micropogonias furnieri, whose geographical distribution within the bay overlaps that of black drum. As of 1995, landings of black drum showed increasing trends both in Argentina and Uruguay. These increments coincide... |
| Tipo: Journal Contribution |
Palavras-chave: Age determination; Growth; Landing statistics; Geographical distribution; Fishery management; Coastal fisheries; Growth; Age determination; Geographical distribution; Fishery management; Coastal fisheries; Http://aims.fao.org/aos/agrovoc/c_3394; Http://aims.fao.org/aos/agrovoc/c_24110; Http://aims.fao.org/aos/agrovoc/c_5083; Http://aims.fao.org/aos/agrovoc/c_24026; Http://aims.fao.org/aos/agrovoc/c_1696. |
| Ano: 2001 |
URL: http://hdl.handle.net/1834/2593 |
| |
|
| |
|
|
| Perrotta, R.G.; Garciarena, A.D.; Madirolas, A.; Cabreira, A.. |
| Chub mackerel (Scomber japonicus) landings corresponding to November 2003-January 2004 and November 2004-January 2005 fishing seasons were analyzed at the Mar del Plata port (Argentina, SW Atlantic). Fourty one samples were taken to measure total length exclusively and 4 sub-samples to record individual data (total length, weight, sex, sexual stage, age according to otoliths reading). Total length ranged 20-50 cm (1 and 8 years old). The most abundant sizes, between 32-37 cm, corresponded to ages 3 and 4, respectively. Most of the fish caught were adult (95%) and mature (85%) specimens. Length-weight, length-age relations were calculated and length-growth, weight-growth parameters estimated. The catch per unit of effort, of high variability (0-2,455 kg... |
| Tipo: Journal Contribution |
Palavras-chave: Landing statistics; Biological sampling; Growth; Fishing effort; Echo surveys; Biomass; Growth; Biomass; Fishing effort; Http://aims.fao.org/aos/agrovoc/c_3394; Http://aims.fao.org/aos/agrovoc/c_926; Http://aims.fao.org/aos/agrovoc/c_24027. |
| Ano: 2009 |
URL: http://hdl.handle.net/1834/3455 |
| |
|
|
| Perrotta, R.G.; Hernandez, D.R.. |
| Bluemouth (Helicolenus dactylopterus), a benthic fish mostly inhabiting at depths between 500 m and 600 m, represents a highly valuable economic resource for local fishermen at the Azores Islands (NE Atlantic). Nominal catches of bluemouth increased from 1990 through 1994, and declined afterwards reaching in 1999 the lowest value recorded. Standardized catch per unit effort (CPUE) was used as an index for stock relative abundance; a General Linear Model, considering several factors that may have affected the fishing efficiency of commercial vessels, was run to obtain this CPUE index. These factors were: fleet type, year, month, and boat size; the last three factors were found to be statistically significant. A discrete version of the Schaefers Biomass... |
| Tipo: Journal Contribution |
Palavras-chave: Stock assessment; Catch/effort; Risks; Mathematical models; Stock assessment; Mathematical models; Http://aims.fao.org/aos/agrovoc/c_24251; Http://aims.fao.org/aos/agrovoc/c_24199. |
| Ano: 2005 |
URL: http://hdl.handle.net/1834/1563 |
| |
|
|
| Perrotta, R.G.; Madirolas, A.; Viñas, M.D.; Akselman, R.; Guerrero, R.A.; Sánchez, M.F.; López, F.; Castro Machado, F.; Macchi, G.J.. |
| In August 1996 acoustic methods were employed to estimate mackerel (Scomber japonicus) abundance in the Buenos Aires, Argentina shelf area of "El Rincón" (4,287 mn2), located between 39°- 40° 30' S. Results showed a biomass estimate of 77,260 t. ASIMRAD EK-500 equipment operated with a 38 KHz split-beam transducer was used. Midwater fishing trawls were employed to identify echotraces and to collect mackerel samples.Trawls 4 and 5 were the most successful. Samples included only adult fish (310-470 mm Lt and ages ranging 2-11). Length and weight growth parameters and mortality rates were estimated. Analysis of the stomach contents revealed that mackerel was feeding exclusively on zooplankters over 2 mmlength. The analysis of the characteristics (dimensions... |
| Tipo: Journal Contribution |
Palavras-chave: Abundance; Biomass; Population structure; Zooplankton; Environmental conditions; Echo surveys; Biomass; Population structure; Zooplankton; Environmental conditions; Http://aims.fao.org/aos/agrovoc/c_926; Http://aims.fao.org/aos/agrovoc/c_6115; Http://aims.fao.org/aos/agrovoc/c_15490; Http://aims.fao.org/aos/agrovoc/c_32980. |
| Ano: 1999 |
URL: http://hdl.handle.net/1834/2529 |
| |
|
| |
|
| |
|
| |
| Registros recuperados: 32 | |
|
|
|
