SS1.02 Geochemical Tracers in Calcified Structures: Implications for Fisheries Research
Date: Tuesday, June 11, 2002
Location: Poster Session - VCC
 
PruellRJ, U.S. Environmental Protection Agency, Atlantic Ecology Division, Narragansett, RI 02882, USA, pruell.richard@epa.gov
Taplin, B, K, U.S. Environmental Protection Agency, Atlantic Ecology Division, Narragansett, RI 02882, USA, taplin.bryan@epa.gov
 
STABLE ISOTOPE RATIOS IN ARCHIVED STRIPED BASS SCALES.
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Stable carbon isotope ratios were measured in archived striped bass (Morone saxatilis) scales to identify changes in the feeding behavior of this species over time. Archived scale samples (1982-1997) and striped bass prey items were collected from Chesapeake Bay and surrounding tributaries. Carbon isotope ratios in archived striped bass scales showed a statistically significant increase between 1982 and 1997. Analysis of striped bass prey items from Chesapeake Bay showed that benthic species, especially invertebrates, were isotopically enriched in stable carbon isotopes relative to pelagic fish species. Prey items collected from different locations within Chesapeake Bay showed that samples collected within riverine systems were isotopically depleted relative to those collected in the open portion of the Bay. These results indicate that the changes observed in the carbon isotope ratios of the striped bass scales could be related to changes in the relative proportions of pelagic and benthic food items in the diet of striped bass between 1982 and 1997. These differences may also be related to changes in the feeding locations or feeding habits of the striped bass.