<?xml version='1.0' encoding='utf-8'?>
<oai_dc:dc xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:oai_dc="http://www.openarchives.org/OAI/2.0/oai_dc/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.openarchives.org/OAI/2.0/oai_dc/ http://www.openarchives.org/OAI/2.0/oai_dc.xsd">
  <dc:contributor>Michelle Bartsch</dc:contributor>
  <dc:contributor>Steve Gutreuter</dc:contributor>
  <dc:contributor>Brent C. Knights</dc:contributor>
  <dc:contributor>Lynn Bartsch</dc:contributor>
  <dc:contributor>William B. Richardson</dc:contributor>
  <dc:contributor>Jonathan M. Vallazza</dc:contributor>
  <dc:contributor>Michael T. Arts</dc:contributor>
  <dc:creator>James H. Larson</dc:creator>
  <dc:date>2015</dc:date>
  <dc:description>&lt;p&gt;&lt;span&gt;Large river systems are often thought to contain a mosaic of patches with different habitat characteristics driven by differences in flow and mixing environments. Off-channel habitats (e.g., backwater areas, secondary channels) can become semi-isolated from main-channel water inputs, leading to the development of distinct biogeochemical environments. Observations of adult bluegill (&lt;/span&gt;&lt;i&gt;Lepomis macrochirus&lt;/i&gt;&lt;span&gt;) in the main channel of the Mississippi River led to speculation that the main channel offered superior food resources relative to off-channel areas. One important aspect of food quality is the quantity and composition of polyunsaturated fatty acids (PUFA). We sampled consumers from main-channel and backwater habitats to determine whether they differed in PUFA content. Main-channel individuals for relatively immobile species (young-of-year bluegill, zebra mussels [&lt;/span&gt;&lt;i&gt;Dreissena polymorpha&lt;/i&gt;&lt;span&gt;], and plain pocketbook mussels [&lt;/span&gt;&lt;i&gt;Lampsilis cardium&lt;/i&gt;&lt;span&gt;]) had significantly greater PUFA content than off-channel individuals. No difference in PUFA was observed for the more mobile gizzard shad (&lt;/span&gt;&lt;i&gt;Dorsoma cepedianum&lt;/i&gt;&lt;span&gt;), which may move between main-channel and off-channel habitats even at early life-history stages. As off-channel habitats become isolated from main-channel waters, flow and water column nitrogen decrease, potentially improving conditions for nitrogen-fixing cyanobacteria and vascular plants that, in turn, have low PUFA content. We conclude that main-channel food webs of the upper Mississippi River provide higher quality food resources for some riverine consumers as compared to food webs in off-channel habitats.&lt;/span&gt;&lt;/p&gt;</dc:description>
  <dc:format>application/pdf</dc:format>
  <dc:identifier>10.5268/IW-5.2.781</dc:identifier>
  <dc:language>en</dc:language>
  <dc:publisher>Freshwater Biological Association</dc:publisher>
  <dc:title>Differences between main-channel and off-channel food webs in the upper Mississippi River revealed by fatty acid profiles of consumers</dc:title>
  <dc:type>article</dc:type>
</oai_dc:dc>