Implementation of dynamic reference points and harvest strategies to account for environmentally-driven changes in productivity in Australian fisheries

All fish stocks are subject to some level of environmentally driven change in productivity, primarily recruitment, but also growth. Current harvest strategies assume either a long-term equilibrium or some average, associated target and limit reference points to determine population size and catch limits. In a number of fisheries these approaches are justifiable, but in others the use of equilibrium-based reference points and harvest strategies do not correctly reflect the natural dynamics of stocks where environmentally driven productivity changes occur. This can lead to sub-optimal management, either over-utilising a reduced productivity stock or under-utilising an increased productivity stock. There have been a number of ad hoc efforts to conduct population projections using recent recruitment, rather than average (stock-recruit relationship) for the purposes of recommending multi-year TACs. In this project, these initiatives will be formalised and explored to provide a rigorous basis for determining future recruitment scenarios for use in population projections for a range of fisheries that are subject to changes in productivity from environmental variables.