Oxygen: A Fundamental Property Regulating Pelagic Ecosystem Structure in the Coastal Southeastern Tropical Pacific

Arnaud Bertrand (1, 2, 3) , Alexis Chaigneau (4, 3) , Salvador Peraltilla (3) , Jesus Ledesma (3) , Michelle Graco (3) , Florian Monetti (3, 5) , Francisco P. Chavez (6)

1 UMR EME - Ecosystèmes Marins Exploités
2 IRD - Institut de Recherche pour le Développement
3 IMARPE - Instituto del Mar del Peru
4 ECOLA - Echanges Côte-Large
5 LOCEAN - Laboratoire d'Océanographie et du Climat : Expérimentations et Approches Numériques
6 MBARI - Monterey Bay Aquarium Research Institute

In the southeastern tropical Pacific anchovy (Engraulis ringens) and sardine (Sardinops sagax) abundance have recently fluctuated on multidecadal scales and food and temperature have been proposed as the key parameters explaining these changes. However, ecological and paleoecological studies, and the fact that anchovies and sardines are favored differently in other regions, raise questions about the role of temperature. Here we investigate the role of oxygen in structuring fish populations in the Peruvian upwelling ecosystem that has evolved over anoxic conditions and is one of the world's most productive ecosystems in terms of forage fish. This study is particularly relevant given that the distribution of oxygen in the ocean is changing with uncertain consequences.

Domaines: Océanographie

Arnaud Bertrand, Alexis Chaigneau, Salvador Peraltilla, Jesus Ledesma, Michelle Graco, et al.. Oxygen: A Fundamental Property Regulating Pelagic Ecosystem Structure in the Coastal Southeastern Tropical Pacific. PLoS ONE, 2011, 6 (12), pp.e29558. ⟨10.1371/journal.pone.0029558⟩. ⟨hal-00951673⟩