Tropical marine ecosystems are comprised of a mosaic of habitats, and many fish species move across this complex seascape on a variety of spatial and temporal scales. For example, many reef fish species forage extensively in surrounding seagrass beds, functionally linking these habitats. A central tenet of conservation is habitat representation, partly to fulfil the habitat needs of target species that forage widely. In the Florida Keys National Marine Sanctuary (FKNMS), Sanctuary Preservation Areas (SPAs) are explicitly designed to protect fish populations, yet, they contain only a small area of seagrass. Currently managers have very little data on how much seagrass is required to support different foraging fishes. This project will collect a variety of field and laboratory data to provide clear guidance to managers on seagrass requirements for four model fish species with differing foraging modes (white grunt, yellowtail snapper, mutton snapper, and great barracuda). Project components will collect data on seascape characteristics and their potential to change because of environmental stressors, invertebrate and fish prey abundances, and risk of predation to foraging fishes at three sites (one each in the Upper, Middle, and Lower Keys). The project will also conduct novel experiments to examine food availability in different seagrass types, and fully quantify habitat quality (prey abundance and accessibility). The foraging (seagrass use) of the four model fish species will be quantified by acoustic telemetry, the energetic costs of this foraging will be measured in aquaria, and stable isotope analyses will examine the reliance of the model fishes on seagrass food sources. All data will then be integrated within species-specific bioenergetic models that will estimate the amount of seagrass needed to support foraging in any seascape configuration throughout the FKNMS. The project’s ultimate output will be a user-friendly online tool that allows managers to estimate, for anywhere in the FKNMS, the seagrass area needed within a SPA to support foraging reef fishes under current and future habitat states.