Ecological understanding increasingly depends on FAIR data—that is, data that are Findable, Accessible, Interoperable, and Re-usable. Vast amounts of data are now being generated via long-term studies, new ecological and ocean observatories, citizen science programs, and advanced sensors and instrumentation. Yet, many ecologists are relatively inexperienced with respect to how large, complex data can be most effectively mobilized to address challenging multi-scale questions and hypotheses. This session has three overarching goals. First, speakers showcase challenging problems related to identifying continental scale landscape and ecosystem change, understanding global bird migration patterns, assessing the health of global oceans, and elucidating other key ecosystem patterns and processes—all problems that require access and use of large, heterogeneous data. Second, speakers highlight specific open source tools and services that enable easy discovery, access, aggregation, analysis and visualization of diverse data. Third, speakers introduce effective approaches for learning and applying new tools and services that will support ecologists as they tackle broader, more complex questions and challenges. Consequently, session participants will learn how “big data” is being used to address grand ecological challenges as well as which open tools and services are being used and how to effectively access and employ those tools and services. The session is designed to be of interest to ecologists working at multiple scales and in different ecosystems (e.g., terrestrial, freshwater, marine, polar) as well as students and citizen scientists. Each talk includes high-impact visuals that illustrate ¬open tools supporting one or more elements of the data life cycle (e.g., data discovery/acquisition, quality assurance, analysis, visualization), cumulatively providing session attendees with a new toolbox to explore as well pointers to education resources that can expand their skillsets.