Variation in size of yellowfin tuna (Thunnus albacares) within individual purse-seine sets

Calkins, Thomas P. (1965) Variation in size of yellowfin tuna (Thunnus albacares) within individual purse-seine sets. Inter-American Tropical Tuna Commission Bulletin, 10(8), pp. 461-524.

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Abstract

ENGLISH:Length-frequency samples of yellowfin tuna from 276 individual purse-seine sets were examined. Evidence of schooling by size is presented. Yellowfin schooled with skipjack are smaller and more homogeneous in length than are yellowfin from pure schools. Yellowfin in schools associated with porpoise appear to be more variable in size than yellowfin from other types of schools. No relationship was found between the tonnage of yellowfin in a school and the mean length of the yellowfin. Despite the tendency to school by size, the size variation within individual schools was judged to be enough to complicate greatly any program of regulation aimed at maximizing the yield-per-recruit through increasing the minimum size of yellowfin at first capture. SPANISH: Fueron examinadas las muestras frecuencia-longitud de atún aleta amarilla, de 276 lances individuales de redes de cerco. Se presenta la evidencia de agrupación por tamaños. Los atunes aleta amarilla agrupados con barrilete, son más pequeños y más homogéneos en longitud, que los atunes aleta amarilla de cardúmenes puros. El atún aleta amarilla en cardúmenes asociados con delfines parece ser más variable en tamaño, que el atún aleta amarilla proveniente de otros tipos de cardúmenes. No se encontró relac¡'ón entre el tonelaje del atún aleta amarilla en un cardumen y la longitud media de esta especie. A pesar de la tendencia a agruparse por tamaño, se juzgó, que la variación de tamaño en cardúmenes individuales, sería suficiente para complicar grandemente cualquier programa de reglamentación, dirigido a obtener el máximo del rendimiento por recluta a través del incremento del tamaño mínimo del atún aleta amarilla en la primera captura.

Item Type: Article
Title: Variation in size of yellowfin tuna (Thunnus albacares) within individual purse-seine sets
Personal Creator/Author:
CreatorsEmail
Calkins, Thomas P.
Journal or Publication Title: Inter-American Tropical Tuna Commission Bulletin
Volume: 10
Number: 8
Page Range: pp. 461-524
Date: 1965
Issuing Agency: Inter-American Tropical Tuna Commission
Additional Information: This article is bilingual and contains both Spanish and English translations.
Uncontrolled Keywords: Length-frequency; yellowfin tuna; Thunnus albacare; purse-seine; variaciones tamaños; atún aleta amarilla; redes de cerco
Subjects: Fisheries
Item ID: 2623
Depositing User: Joan Parker
Date Deposited: 24 Sep 2009 12:08
Last Modified: 29 Sep 2011 18:48
URI: http://aquaticcommons.org/id/eprint/2623

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