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| 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 |
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| 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 |
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| Montoya, N.G.; Akselman, R.; Pájaro, M.; Perrotta, R.G.; Carreto, J.I.. |
| Spring blooms of the toxic dinoflagellate Alexandrium tamarense in the Argentine sea produce shellfish toxicity through the parallytic shellfish poison (PSP)accumulation. The trace PSP content in the mackerel Scomber japonicus liver was previously demonstrated in the Buenos Aires province coastal region (Carreto et al, 1993a),and a certain capability to accumulate the toxins was suggested.However, it was up to spring 1993 when a great number of PSP intoxicated mackerels where detected for the first time in a wideshelf area off the Buenos Aires province. This area, known as 'El Rincón' (39°00'-40°30'S), has become a growing importance mackerel fishing ground during the last few years. A high PSP concentration was determined in those mackerels, being the... |
| Tipo: Journal Contribution |
Palavras-chave: Toxicity; Algal blooms; Biological poisons; Stomach; Toxicity; Stomach; Algal blooms; Http://aims.fao.org/aos/agrovoc/c_7826; Http://aims.fao.org/aos/agrovoc/c_7422; Http://aims.fao.org/aos/agrovoc/c_32367. |
| Ano: 1997 |
URL: http://hdl.handle.net/1834/1939 |
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| Balech, E.; Akselman, R.; Negri, R.M.. |
| The present work is a supplement of the monography "The dinoflagellates of the Southwestern Atlantic" by E. Balech (in press). Eightenn species belonging to the genera Ceratium, Dinophysis, Diplopelta, Gonyaulax, Heterochisma. Oblea, Oxyphysis, and Protoperidinium are discussed on accurt of their presence, up to the present unknown in the area. Comments on their geographical distributions, ecological requirements and morphological details are included in the work. |
| Tipo: Journal Contribution |
Palavras-chave: Organism morphology; Geographical distribution; New records; Phytoplankton; Geographical distribution; Phytoplankton; Http://aims.fao.org/aos/agrovoc/c_5083; Http://aims.fao.org/aos/agrovoc/c_13344. |
| Ano: 1984 |
URL: http://hdl.handle.net/1834/2042 |
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