A Systematic Evaluation of Flood Pulse Effects on 22 Exploited Fish Taxa of Amazonian River-Floodplains

River flood pulses enhance floodplain productivity and influence floodplain fish population dynamics.  Different measures of flood pulses have been used to evaluate how flood pulses affect fish populations, however it is unclear which of these measures have the greatest influences on fish population dynamics.  The goal of this study was to evaluate which flood pulse variables (i.e, maximum stage, season duration, flooded area) have the greatest influences on floodplain fish populations.  Taxa-specific regression models using catches from 11 years of fishing trips in the Central Amazon were created to evaluate the relationship between flood pulse variables and catches of floodplain fishes.  Models for 22 taxa revealed that the mean rate of water level rise (MRWR) and low water index 2 (LWI₂) – an index of low water duration and river stage – of previous years (t-i) had the greatest influence on catch in year t, although other variables were influential.  Our results suggest that flood pulse variables that incorporate measures of severity and duration account for the ability of fish to utilize floodplain resources and have the greatest influence on floodplain fish catches.  Overall, this information can be used to better understand, conserve, and manage exploited floodplain fish populations.