This study is part of the Gulf of Mexico-Shipwreck Corrosion, Hydrocarbon Exposure, Microbiology, and Archaeology (GoM-SCHEMA) Study. The natural breakdown of wooden and metal-hulled shipwrecks over time is influenced by microorganisms. Microorganisms colonize a shipwreck immediately after the vessel comes to rest on the seafloor. Bacteria and archaea form communities on the surface of exposed materials such as wood or metal. As the communities grow and expand, a biofilm forms. This biofilm establishes conditions that allow for settlement of higher trophic levels which, in turn, attract larger, mobile fauna. This diverse community of micro- and macrofauna comprises a small ecosystem. In time, the shipwreck becomes an artificial reef. The nature of the biofilm community structure and function is not entirely understood. The goal of this study is to understand the changes to deep-sea biofilms caused by in situ exposure to residual spill contaminants through a comparative study involving historic shipwrecks within and external to the acute spill footprint.