Parnel et al.: Effects of oceanic conditions on ichthyoplankton communities in the Columbia River plume 
171 
nia Current circulation patterns will alter zooplankton 
prey that larval fish feed on. 
Climate-induced change in upwelling patterns, sea 
surface temperatures, and perhaps Columbia River flows 
will have large effects on the larval fish within our 
study area and in the broader California Current region. 
We examined interannual variation in the abundance 
of fish eggs and larvae in the Columbia River plume 
and have shown that the ichthyoplankton community 
changes in relation to the dynamic oceanographic pro- 
cesses of this region. However, research over a greater 
area and on a longer time scale is needed to determine 
the effects of these processes on the ichthyoplankton 
community, as well as to determine how recruitment 
of marine fish is being affected by regional and larger- 
scale variability in the marine environment. 
Acknowledgments 
We thank P. Bentley and G. Krutzikowsky for field 
assistance, T. Auth and M. Busby for assistance in 
identifying eggs and larvae, and T. Auth, S. Bollens, 
and M. Busby for comments on an earlier version of the 
manuscript. Funding was provided by the Bonneville 
Power Administration and National Oceanic Atmospheric 
Administration’s (NOAA) Fisheries and the Environment 
Initiative. The lead author was supported in part by 
an appointment to the NOAA’s research participation 
program administered by the Oak Ridge Institute for 
Science and Education. 
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