Journal Article

Behaviour of the southern sea lion (<i>Otaria flavescens</i>) and consumption of the catch during purse-seining for jack mackerel (<i>Trachurus symmetricus</i>) off central Chile

L.A Hückstädt and T Antezana

in ICES Journal of Marine Science

Published on behalf of ICES/CIEM

Volume 60, issue 5, pages 1003-1011
Published in print January 2003 | ISSN: 1054-3139
Published online January 2003 | e-ISSN: 1095-9289 | DOI: http://dx.doi.org/10.1016/S1054-3139(03)00100-0
Behaviour of the southern sea lion (Otaria flavescens) and consumption of the catch during purse-seining for jack mackerel (Trachurus symmetricus) off central Chile

More Like This

Show all results sharing these subjects:

  • Environmental Science
  • Marine and Estuarine Biology

GO

Show Summary Details

Preview

The fishery for jack mackerel (Trachurus symmetricus) off central Chile competes for the resource with southern sea lions (Otaria flavescens), and during purse-seining makes the fish more accessible to the pinnipeds. Interactions with sea lions were recorded during 31 purse-seine sets off central Chile during October 1999. The sea lion behaviour associated with the fishing operations was distinctive. Feeding, movement, predator avoidance, and resting displays were identified. The sea lions approached the purse-seiner as soon as net-setting began. The number of sea lions per set (0–50) was seemingly unaffected by school size of jack mackerel, number of purse-seiners on the fishing ground, whether fishing was by night or by day, the presence of killer whales, or the species being targeted. However, the number of sea lions at a purse-seine differed significantly between fishing grounds. Other effects of fishing operations on O. flavescens included incidental mortality and capture. The amount of fish consumed by the sea lions at a set was as much as 0.4% of the catch. The results of the interaction are documented and discussed in the light of likely interaction with the whole sea lion population, as well as the impact of the interaction on the fishery.

Keywords: behaviour; central Chile; Otaria flavescens; purse-seine fishery; Trachurus symmetricus

Journal Article.  4838 words.  Illustrated.

Subjects: Environmental Science ; Marine and Estuarine Biology

Full text: subscription required

How to subscribe Recommend to my Librarian

Users without a subscription are not able to see the full content. Please, subscribe or login to access all content.