FEISTY Fortran library and R package to integrate fish and fisheries with biogeochemical models

<ol><li>The FishErIes Size and functional TYpe model (FEISTY) is a mechanistic ecosystem model that fully integrates ecosystem structure across trophic levels through functional types.</li><li>We present an R package that enables users to run simulations ranging from a 0D chemostat to full global scales. The library is written in Fortran90 with an R interface and provides a web application for visual exploration.</li><li>We present and compare results from four core configurations across a range of depths, productivity and fishing levels, and we assess the convergence of solutions as the number of size classes is increased.</li><li>The model has historically been coupled to biogeochemical models of mesozooplankton and detritus production, but it can also be applied in a stand-alone version. We demonstrate the library to set up and simulate fish communities under varying productivity of mesozooplankton and benthos, and top-down forcing from fishing.</li><li>We outline three strategies for coupling FEISTY with biogeochemical model output and discuss future directions and open issues.</li></ol>