Abstract

<p><strong> </strong>Isla del Coco National Park (ICNP), Costa Rica, is renowned for its large aggregations of pelagic species, especially sharks (Carcharhinidae and Sphyrnidae), billfish (Istiophoridae) and tuna (Scombridae). The high abundance of these sought after species, attracts commercial fishing vessels that enter the protected waters of the Park. Illegal fisheries thus represent one of the biggest threats to the ecological integrity of this World Heritage Site. The ICNP dedicates important resources to protection and control via regular surveillance patrols, along the 12 nautical miles that have Marine Protected Area (MPA) status. During 2012, 2013 and between January and August 2014, 405 surveillance patrols within the MPA found 108 fishing lines, more than 13 000 hooks, seized more than 500 km of fishing line and 257 pelagic individuals. The yellowfin tuna (<em>Thunnus albacares</em>) was the most abundant species, representing more than 72.3 % of the total catch; seized individuals had a mean total length of 153.35±23.19 cm (Min=90 cm; Max=190 cm); which indicates that most individuals were adults. Analysis of monthly CPUE showed that the highest relative abundance of illegally caught <em>T. albacores</em> was between May and August of each year, with a mean relative abundance of 26.13±54.71, 11.63±23.79, 13.71±24.52 tunas per 1 000 hooks in 2012, 2013, 2014, respectively. This species had a high survival rate (nearly 80 % of the individuals found on the lines were still alive), probably due to the short fishing lines used by illegal fishermen, combined with the swift intervention of rangers. The CPUE of <em>T. albacares</em> found in this study is greater than records in Costa Rica’s Exclusive Economic Zone (0.74 and 0.44 per 1 000 hooks respectively). These results highlight the importance of ICNP as an aggregation site for <em>T. albacares</em> and the need for its effective protection. It is important that ranger intervention continue to be as rapid and effective as possible, in order to decrease the impact of illegal fishing on the marine biodiversity of the ICNP. </p><div> </div>

Highlights

  • La protección absoluta de un Área Marina Protegida (AMP) generalmente resulta en un rápido incremento en la biomasa, abundancia y talla promedio de las poblaciones explotadas (Roberts, Hawkins, & Gell, 2005); además, produce un aumento significativo en la diversidad de especies (Halpern, 2003)

  • Los análisis reproductivos efectuados en 45 T. albacares hallados muertos en las líneas de pesca revelan que el 90 % de estos experimentaba un avanzado estado de desarrollo gonadal, esto tanto en hembras como los machos

  • Sustainable fishing gear: the case of modified circle hooks in a Costa Rican longline fishery

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Summary

MATERIALES Y METODOS

Área de Estudio: El PNIC se localiza en el Océano Pacífico (5o30’-5°34’ N - 87°01’87o06’ W), 496 km al suroeste de Cabo Blanco, Costa Rica. El PNIC posee una extensión de 24 km en la parte terrestre y un área marina protegida con protección absoluta que se extiende 12 millas náuticas (22.22 km) alrededor de la Isla (Cortés, 2008) (Fig. 1). El PNIC pertenece al Área de Conservación Marina Isla del Coco (ACMIC), la cual además posee una zona contigua de alrededor de 1 000 000 ha denominada Área Marina de Manejo Montes Submarinos (AMM-MS). Los datos analizados sobre las pesquerías ilegales y especies capturadas provienen de líneas de pesca halladas dentro del PNIC durante el periodo 2012-2013 y entre enero y agosto del 2014. Patrullajes de control y protección en el AMP del PNIC: Las condiciones oceanográficas, la disponibilidad de embarcaciones, personal, entre otras cosas hacen que el número de

PN Isla del Coco
Número de Líneas halladas
Número de Líneas
Findings
SUGERENCIAS PARA LA CONSERVACIÓN Y LA INVESTIGACIÓN
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