Résumé
Eastern boundary upwelling ecosystems are extremely dynamic over a wide range of spatiotemporal scales. This is particularly the case for the Humboldt Current ecosystem, which is characterized by short term, seasonal, inter- annual (Niño/Niña events) and inter-decadal regimes of variability. In such a context, we aimed to study how equatorial physical forcing may affect coastal water mass distribution, fish distribution and fishers spatial behaviour. For that purpose, we used data from scientific surveys conducted in Peru between 1983 and 2003 to characterize water masses, fish abundance and spatial distribution. Fishers spatial behaviour was characterized from satellite vessel monitoring system data from 1999 to 2003. From a statistical exploration and wavelet analysis performed on a set of indicators, there was evidence that (1) fish spatial distribution is well explained by water-mass spatial dynamics supporting habitat based determination of fish distribution; (2) fishers efficiency is constrained by the way fish biomass fills the space, and in different ways according to the spatial scale; (3) fishers spatial behaviour responds to fish spatial distribution across scales (4) energy peaks for the studied indicators presented the same intra-seasonal and inter-annual characteristic scales as the equatorial Kelvin waves. We conclude that fish biomasses and spatial distributions as well as spatial behaviour of fishers were modulated by coastal physical activity forced at distance by the Kelvin equatorial waves.