Mortalidad embrionaria por canibalismo en la anchoíta argentina Engraulis anchoita Hubbs y Marini, 1935
The Argentine anchovy Engraulis anchoita Hubbs and Marini, 1935, is, in terms of biomass, the greatest fish resource in the Southwest Atlantic. It plays a key role in the Argentine fisheries as trophic support for several commercially exploited species. Argentine anchovy migrate to their coastal spa...
| Autores: | , , |
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| Tipo de recurso: | artículo |
| Fecha de publicación: | 2001 |
| País: | España |
| Institución: | Consejo Superior de Investigaciones Científicas (CSIC) |
| Repositorio: | DIGITAL.CSIC. Repositorio Institucional del CSIC |
| OAI Identifier: | oai:digital.csic.es:10261/325906 |
| Acceso en línea: | http://hdl.handle.net/10261/325906 |
| Access Level: | acceso abierto |
| Palabra clave: | Pesquerías Canibalismo anchoíta argentina Engraulis anchoita huevos depredación zooplancton |
| Sumario: | The Argentine anchovy Engraulis anchoita Hubbs and Marini, 1935, is, in terms of biomass, the greatest fish resource in the Southwest Atlantic. It plays a key role in the Argentine fisheries as trophic support for several commercially exploited species. Argentine anchovy migrate to their coastal spawning grounds during spring and summer; and at least two populations co-exist in the spawning- area: the northern, or Buenos Aires, population (from 33° LS to -41° LS) and the southern, or Patagonian, population (from 41° LS to -48° LS). From a trophic standpoint, this a poor habitat for such a large number of anchovies, and copepods predominate amont their prey organisms to findings from our analysis of stomach contents. No relationship was found between consumption and density of plankton eggs; however, in the northern population, there was evidence of an increase in cannibalism as mezooplancton density decreased. Regarding the number of eggs ingested, we estimated a mean value of 10.0 eggs/fish (standard desviation: 5.04) and 0.8 (s.d.: 0.44) eggs/fish (s.d.e.: = 0.44) for the Buenos Aires and Patagonian populations, respectively. The mean number of anchovy eggs per stomach was 14.1 (s.d. 7.9) for nocturnal samples and 1.0 (s.d.: 0.4) for daytime samples. Consumption of eggs over a 12 h feeding period was estimated to have caused 27 % of the total eggs mortality for the Buenos Aires stock and 1-2 % for the Patagonian stock. Our results indicate that intraespecific predation on eggs by anchovy adults represents a high percentage of the total embryonic mortality, especially in areas where other food resources are scarce. |
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