Examining broad-scale patterns in marine food-webs and ecosystems is essential for understanding macro-scale patterns and processes and could support a greater adoption of general ecosystem-based management practices. This talk will present recent work undertaken by a team of scientist connected through the international GLOBEC program CLIOTOP - Climate Impacts on Oceanic Top Predators. Focusing on three species of oceanic tuna (yellowfin, bigeye, albacore), two global databases were compiled: (i) >20,000 stomach samples including more than 300 prey taxa from tunas collected 1969-2014; and (ii) >6,000 bulk nitrogen and carbon stable isotope records, 2000-2015. These datasets were used to undertake the first inter-oceanic comparisons of top predator diets and isotopes ever conducted at a global scale. Broad, macro-scale trophic patterns in pelagic ecosystems were quantitatively assessed using a modified classification tree approach for stomach contents data and generalised additive mixed models for isotope data. Interpolated results were relayed on oceanographic contour maps that characterise the global distribution patterns of tuna prey, diet diversity and trophic positions. Global and ocean basin differences within and between each of the three tuna species studied were detected. Results from these analyses provide valuable depictions of the trophic pathways that underlie the production of tunas and other pelagic predators in the open ocean. Modelling efforts also allowed hypotheses to be posed about future food web interactions in a warming ocean.