Age estimation obtained from analysis of cotopus (Octopus vulgaris Cuvier, 1797) beaks: improvements and comparisons

Two methods are currently available for age estimation in octopus beaks. They have been applied to the same specimen from a sample of 30 individuals of Octopus vulgaris caught in central-eastern Atlantic waters. These techniques aim at revealing growth increments in the rostrum sagittal sections (RS...

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Detalles Bibliográficos
Autores: Perales-Raya, Catalina, Bartolomé-Baraza, Aurora, Santamaría, María Teresa García, Pascual-Alayón, Pedro José, Almansa, Eduardo
Tipo de recurso: artículo
Fecha de publicación:2010
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/324815
Acceso en línea:http://hdl.handle.net/10261/324815
Access Level:acceso abierto
Palabra clave:Centro Oceanográfico de Canarias
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Descripción
Sumario:Two methods are currently available for age estimation in octopus beaks. They have been applied to the same specimen from a sample of 30 individuals of Octopus vulgaris caught in central-eastern Atlantic waters. These techniques aim at revealing growth increments in the rostrum sagittal sections (RSS) and lateral wall surfaces (LWS) of octopus upper and lower beaks. Both methods were improved to reduce the time of sample preparation and to enhance the appearance of the increments. For each individual, two independent readings were done for upper and lower beak sections, as well as for the lateral wall surfaces. Vertical reflected light (epifluorescence) and image analysis system were shown to be useful in the observation and analysis of the sequence of increments. Precision of the ageing, increment counts obtained by both techniques, and increment widths were discussed. Using upper beak RSS led to more precise age estimates, whereas preparing LWS was quicker and simpler, and revealed a higher number of increments. Therefore, our study recommends counting growth increments in LWS of beaks to age adult