Publications des scientifiques de l'IRD

Tolotti M. T., Bach Pascal, Hazin F., Travassos P., Dagorn Laurent. (2015). Vulnerability of the oceanic whitetip shark to pelagic longline fisheries. Plos One, 10 (10), p. e0141396 [17 p.]. ISSN 1932-6203.

Titre du document
Vulnerability of the oceanic whitetip shark to pelagic longline fisheries
Année de publication
2015
Type de document
Article référencé dans le Web of Science WOS:000363249300049
Auteurs
Tolotti M. T., Bach Pascal, Hazin F., Travassos P., Dagorn Laurent
Source
Plos One, 2015, 10 (10), p. e0141396 [17 p.] ISSN 1932-6203
A combination of fisheries dependent and independent data was used to assess the vulnerability of the oceanic whitetip shark to pelagic longline fisheries. The Brazilian tuna longline fleet, operating in the equatorial and southwestern Atlantic, is used as a case study. Fisheries dependent data include information from logbooks (from 1999 to 2011) and on-board observers (2004 to 2010), totaling 65,277 pelagic longline sets. Fisheries independent data were obtained from 8 oceanic whitetip sharks tagged with pop-up satellite archival tags in the area where longline fleet operated. Deployment periods varied from 60 to 178 days between 2010 and 2012. Tagging and pop-up sites were relatively close to each other, although individuals tended to travel long distances before returning to the tagging area. Some degree of site fidelity was observed. High utilization hotspots of tagged sharks fell inside the area under strongest fishing pressure. Despite the small sample size, a positive correlation between tag recorded information and catch data was detected. All sharks exhibited a strong preference for the warm and shallow waters of the mixed layer, spending on average more than 70% of the time above the thermocline and 95% above 120 m. Results indicate that the removal of shallow hooks on longline gear might be an efficient mitigation measure to reduce the bycatch of this pelagic shark species. The work also highlights the potential of tagging experiments to provide essential information for the development of spatio-temporal management measures.
Plan de classement
Ressources halieutiques [040]
Description Géographique
ATLANTIQUE ; BRESIL ; ZONE EQUATORIALE
Localisation
Fonds IRD [F B010065412]
Identifiant IRD
fdi:010065412
Contact