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The food webs of littoral, pelagic, and littoral-pelagic ecotone (interface) regions of a large subtropical lake were investigated using stable isotope ratio methods, expanding the focus of a previous fish-only study to include other food web components such as primary producers and invertebrates. In these food webs, delta13C increased approximately 4 per thousand and delta15N increased approximately 10 per thousand from primary producers to fish. The delta15N of fish was approximately 9 per thousand in the littoral zone, approximately 10 per thousand in the ecotone, and approximately 12 per thousand in the pelagic zone. The cross-habitat enrichment in fish 15N corresponded with both an increase in the size of fish...
The Forest and Rangeland Ecosystem Science Center 's mission is to provide scientific understanding and the technology needed to support sound management and conservation of our nation's natural resources, with emphasis on western ecosystems. The scientists from FRESC capitalize on their diverse expertise to answer critically important scientific questions shaped by the equally diverse environments of the western United States. FRESC scientists collaborate with each other and with partners to provide rigorous, objective, and timely information and guidance for the management and conservation of biological systems in the West and worldwide. Research activities are concentrated in Washington, Oregon, Idaho, Nevada,...