Stable isotopes values (corrected) for freshwater fish and their putative preys for two different rivers in England. Site 1 spreadsheet: Gloucester-Sharpness Canal (51.7249 N, 2.4733 W), England. Data contains: * Name of site * Taxa * Species name * Length * Tissue taken * Stable isotope values (corrected) Site 2 spreadsheet: River Bure (upstream of the upper limit of saline incursion at Horning), England Data contains: * Species * Length * Stable isotope values (corrected)