Albacore (Thunnus alalunga) larval index in the Western Mediterranean Sea, 2001-2015
Larval abundance indices express standardized abundances of larval densities from ichthyoplankton surveys. For more than two decades these indices have been used to assess the trends of the spawning stock biomass of various species in the Gulf of Mexico, being incorporated into the population models...
| Autores: | , , , , |
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| Formato: | artículo |
| Estado: | Versión publicada |
| Fecha de publicación: | 2017 |
| País: | España |
| Recursos: | Consejo Superior de Investigaciones Científicas (CSIC) |
| Repositorio: | DIGITAL.CSIC. Repositorio Institucional del CSIC |
| OAI Identifier: | oai:digital.csic.es:10261/323868 |
| Acesso em linha: | http://hdl.handle.net/10261/323868 |
| Access Level: | acceso abierto |
| Palavra-chave: | Abundance Centro Oceanográfico de Baleares Pesquerías Albacore Catchability Fish larvae Fishery sciences Mathematical models Pelagic environment Spawning Tuna fisheries Ichthyoplankton Biomass |
| Resumo: | Larval abundance indices express standardized abundances of larval densities from ichthyoplankton surveys. For more than two decades these indices have been used to assess the trends of the spawning stock biomass of various species in the Gulf of Mexico, being incorporated into the population models applied by ICCAT. Recently, the delta-lognormal models used for the calculation of the indices have been improved to incorporate the environmental variability and have been applied in the Balearic Sea to obtain a larval index for bluefin tuna (Thunnus thynnus). Here we apply the same methodological approach to calculate a larval index of albacore (Thunnus alalunga) from surveys conducted from 2001 to 2015 in the Balearic Sea, the most relevant spawning ground of this species in the Western Mediterranean. Results show a decreasing trend on albacore larval abundances and significant lower abundances from 2013 to 2015. This larval index, standardized for gears, sampling coverage, hour, salinity, date and sea surface temperature, attempt to provide information on the dynamic of the western Mediterranean stock of albacore, for which not much information available for assessment is available |
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