This dataset includes results from a study of the trophic ecology of northwest Atlantic sharks including Blue, Mako, and Thrasher sharks. Samples were collected and processed by Alexander Rubin for stable isotope analysis at the Environmental Protection Agency, Atlantic Coastal Sciences Branch (ACSB). Samples were analyzed for percent carbon (C) and nitrogen (N) content and stable isotopes of C and N using an elemental analyzer (EA) paired with an isotope ratio mass spectrometer (IRMS). Data were used to assess the changes in feeding patterns and trophic levels of Atlantic sharks over time.