Campus Community:

Please join us for a talk at HSU by Richard Brodeur as our next Michael G. Scott Distinguished Speaker on Wednesday, April 17 at 4pm.

Details:

Wed, April 17, 4:00pm, Wildlife and Fisheries Building Room 258.  Richard Brodeur - "Changing ocean conditions: Understanding climate effects on biota in the Northeast Pacific".

Ric leads a team of researchers and students at NOAA's Northwest Fisheries Science Center working on several projects including feeding ecology of juvenile salmon and other fishes in the Columbia River plume, distribution of salmon and associated biota relative to hydrographic features and migration patterns of salmon in coastal waters. His research talk will focus on looking at the impact of climate and environmental conditions on forage taxa in the Northern California Current.  The full abstract is below.

We hope to see you there!

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Changing ocean conditions: Understanding climate effects on biota in the Northeast Pacific

Richard D. Brodeur

NOAA, Northwest Fisheries Science Center,

CEOAS, Oregon State University,

Hatfield Marine Science Center, Newport, OR 97365, USA. 

E-mail: rick.brodeur@noaa.gov

The Northeast Pacific Ocean and in particular the Northern California Current is a highly productive region that has undergone substantial interannual and decadal-scale variability in recent decades. Forage taxa play a central role in the transfer of energy from lower to higher trophic levels.  Ocean conditions may influence this energy pathway in the northern California Current (NCC) ecosystem.  The recent unprecedented prolonged warming in the NCC provides a unique opportunity to better understand the connection between ocean conditions and forage taxa abundance and distribution patterns and feeding.  I present findings from several studies that suggest that the recent warming period associated with the ‘Warm Blob' and El Niño affected forage significantly. Zooplankton and ichthyoplankton surveys over the last two decades showed dramatic changes in species composition and phenology. Pelagic trawl surveys were conducted off Oregon and Washington during early summer of 2011 and 2013-2016 and examined for interannual changes in spatial distribution of fish and invertebrate taxa.  The community was significantly different in both 2015 and 2016 than the earlier cool years.  Crustacean plankton densities were extremely low in both years, and the invertebrate composition became dominated by gelatinous zooplankton.  Stomach collections of multiple forage fishes off the Washington and Oregon coasts were examined from June during recent warm years (2015 and 2016) and compared to previous collections from 2000, 2002, 2011, and 2012 (average or cool years).  Fish feeding habits varied significantly between cold and both average and warm periods.  Euphausiids, decapods, and copepods were the main prey items of the forage fishes in cool years; however, gelatinous zooplankton were consumed in higher quantities in warm years.  The substantial reorganization of the pelagic forage community has the potential to lead to major alterations in trophic functioning in this normally productive ecosystem.