Integrating reproductive ecology, early life dynamics and mesoscale oceanography to improve albacore tuna assessment in the Western Mediterranean

Albacore tuna is a pelagic top predator of high ecological and commercial relevance worldwide. Despite the importance of this species, there is only limited knowledge of its life cycle, reproductive dynamics and early life ecology. In the Mediterranean, where the assessment is based on data-poor met...

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Detalles Bibliográficos
Autores: Alvarez Berastegui, Diego, Saber, Sámar, Ingram, G.W., Reglero, Patricia, Macías-López, Ángel David, García-Barcelona, Salvador, Ortiz-de-Urbina-Gutiérrez, José María, Tintoré, Joaquim, Alemany, Francisco, Díaz-Barroso L
Tipo de recurso: artículo
Fecha de publicación:2018
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/326587
Acceso en línea:http://hdl.handle.net/10261/326587
Access Level:acceso abierto
Palabra clave:Early life
Pesquerías
Centro Oceanográfico de Málaga
Tuna fisheries
Fisheries assessment
Long line
Western Mediterranean
Larval habitat
Operational fisheries oceanography
Descripción
Sumario:Albacore tuna is a pelagic top predator of high ecological and commercial relevance worldwide. Despite the importance of this species, there is only limited knowledge of its life cycle, reproductive dynamics and early life ecology. In the Mediterranean, where the assessment is based on data-poor methods, the status of the albacore population remains uncertain. Here we combine information from commercial fisheries, ichthyoplankton surveys and oceanographic data in the Western Mediterranean Sea to identify the geographical location of the main spawning areas and larval habitats. We applied this information to develop a habitat-corrected larval abundance index providing information on early life dynamics. The larval index was compared with fisheries-dependent indices used for the stock assessment of the Mediterranean albacore. The results allowed the identification of the main spawning grounds, located around the Balearic Sea, and the role of oceanographic conditions when studying larval abundances. The larval abundance index shows a significant negative trend during the last decade, indicating a potential reduction in the spawning stock biomass, which is consistent with the trend observed from the fisheries-dependent indices. We discuss how the systematic integration of information from ichthyoplankton surveys and hydrography to improve assessment is an example of operational fisheries oceanography in practice.