Pesca con anzuelos en barcos palangreros del Océano Pacífico mexicano: efectos en la captura y peso de tiburones y otras especies

Revista de biología marina y oceanografía, ISSN 0717-3326, Vol. 44, Nº. 1, 2009, pags. 163-172 04/2009; 44(1). DOI: 10.4067/S0718-19572009000100016
Source: OAI


We analyzed the effects of two hook types and two bait types on the catch rate of long liners from the northwest Pacific Ocean off Mexico. In 47 sets, from four commercial fishing trips done during March 2005 to August 2006, we used conventional J-style 9/0 11º offset hooks and experimental circle 16/0 0º offset hooks. We used two bait types: jumbo squid (Dosidicus gigas) and striped mullet juveniles (Mugil cephalus). A factorial experiment split-plot design was applied. A total of 1304 organisms were caught, where 86.5% were sharks, and blue shark (Prionace glauca) was the dominant specie and 13.5% from other species. While the hook type did not affect significantly the catch rate and weight of sharks and other species, the bait type had a significant effect, mainly on the catch rate of blue shark, silky shark (Carcharhinus falciformis), dolphinfish (Coryphaena hippurus), and the weight of total catch. The Tukey test showed that the mean catch rate of blue shark, silky shark, dolphinfish, total catch and weight were higher for squid bait than for striped mullet Resumen.- Se evaluó el efecto de dos tipos de anzuelos y dos tipos de carnada en la tasa de captura de barcos palangreros en el noroeste del Océano Pacífico mexicano. Se realizaron cuatro viajes de pesca comercial con un total de 47 lances, entre marzo de 2005 y agosto de 2006. Los dos tipos de anzuelos usados fueron: recto 11º de inclinado 9/0 de uso tradicional y circular plano 16/0 (experimental). Se utilizaron dos tipos de carnada: calamar gigante (Dosidicus gigas) y peces juveniles de lisa (Mugil cephalus). Se aplicó un diseño experimental factorial en parcelas divididas (�split-split-plot�). Se capturó un total de 1304 ejemplares, de los cuales 86,5% fueron tiburones, siendo el tiburón azul (Prionace glauca) la especie dominante y 13,5% estuvo constituido por otras especies. Los resultados mostraron que el tipo de anzuelo no presentó diferencias significativas en la tasa y peso de la captura de tiburones y de las otras especies consideradas como pesca incidental; el tipo de carnada presentó un efecto significativo en la tasa de captura, principalmente en tiburón azul, tiburón jaquetón (Carcharhinus falciformis), dorado (Coryphaena hippurus), así como en el peso de la captura total. La prueba de Tukey, mostró que la carnada de calamar presentó una media superior a la carnada de lisa en la tasa de captura del tiburón azul, piloto, dorado, captura y peso total.

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