Benthic invertebrates are a crucial link in trophic energy transfer in the Arctic Ocean. However, the organic matter sources sustaining these organisms are not well understood. As filter feeders, they could theoretically feed on sinking particulate organic matter from sea ice algae, phytoplankton, terrestrial plant matter, or microbially reworked organic matter. The proportional contribution of each of these sources is currently not known, and might additionally undergo significant shifts as the Arctic environment changes in the future. I propose using amino acid stable isotope fingerprinting to identify temporal variation in the proportional input of organic matter sources in benthic invertebrate species. I plan to analyze Serripes spp. and Macoma spp. samples collected from 2004 to 2015 in the Chukchi and Beaufort Seas for short-term changes in inputs. I also plan to analyze archaeological bivalve samples from Barrow, Alaska to establish a pre-industrial baseline. Identifying how organic matter pathways have changed both over long time scales and in recent years will yield a better understanding of how human activities are altering the Arctic ecosystem, and can allow us to predict how ongoing changes in the Arctic can impact trophic pathways in the future.