Previous Article |
Table of Contents
| Next Article 
BIOLOGICAL SCIENCES / ECOLOGY
Complex interplays among population dynamics, environmental forcing, and exploitation in fisheries
,
,
*Institut Français de Recherche pour l'Exploitation de la Mer and Institut de Recherche pour le Développement, Centre de Recherche Halieutique Méditerranéen et Tropical, Avenue Jean Monnet, BP 171, 34203 Sète Cedex, France; Centre for Ecological and Evolutionary Synthesis, Department of Biology, University of Oslo, P.O. Box 1066, Blindern, N-0316 Oslo, Norway; ¶Centre National de la Recherche Scientifique, Unité Mixte de Recherche 7625, Ecole Normale Supérieur, 46, Rue d'Ulm, 75230 Paris Cedex 05, France; ||Unité de Recherche GEODES 079 Centre, Institut de Recherche pour le Développement, Ile de France, 32, Avenue Henri Varagnat, 93142 Bondy Cedex, France; **Secretariat of the Pacific Community, BP D5, 98848 Nouméa Cedex, New Caledonia; Département Ecologie et Modèles pour l'Halieutique, Institut Français de Recherche pour l'Exploitation de la Mer, BP 21105, 44311 Nantes Cedex 03, France; and Department of Coastal Zone Studies, Flødevigen Research Station, Institute of Marine Research, N 4817 His, Norway
Edited by Simon A. Levin, Princeton University, Princeton, NJ, and approved February 12, 2008 (received for review September 24, 2007)
The patterns of variations in fisheries time series are known to result from a complex combination of species and fisheries dynamics all coupled with environmental forcing (including climate, trophic interactions, etc.). Disentangling the relative effects of these factors has been a major goal of fisheries science for both conceptual and management reasons. By examining the variability of 169 tuna and billfish time series of catch and catch per unit effort (CPUE) throughout the Atlantic as well as their linkage to the North Atlantic Oscillation (NAO), we find that the importance of these factors differed according to the spatial scale. At the scale of the entire Atlantic the patterns of variations are primarily spatially structured, whereas at a more regional scale the patterns of variations were primarily related to the fishing gear. Furthermore, the NAO appeared to also structure the patterns of variations of tuna time series, especially over the North Atlantic. We conclude that the patterns of variations in fisheries time series of tuna and billfish only poorly reflect the underlying dynamics of these fish populations; they appear to be shaped by several successive embedded processes, each interacting with each other. Our results emphasize the necessity for scientific data when investigating the population dynamics of large pelagic fishes, because CPUE fluctuations are not directly attributable to change in species' abundance.
Atlantic tuna | North Atlantic Oscillation | time-series analysis
The authors declare no conflict of interest.
This article is a PNAS Direct Submission.
This article contains supporting information online at www.pnas.org/cgi/content/full/0709034105/DCSupplemental.
To whom correspondence may be addressed. E-mail: jean.marc.fromentin{at}ifremer.fr or n.c.stenseth{at}bio.uio.no
© 2008 by The National Academy of Sciences of the USA
CiteULike 
Complore 
Connotea 
Del.icio.us 
Digg What's this?
