Social-Ecological Vulnerability of Forage Fish and Fishermen to Climate Change

Marine forage species such as squid, anchovies, and sardines serve as dominant primary consumers, targets of some of the largest fisheries in the world, and essential food for higher trophic level species like marine mammals, seabirds, and larger fishes. Contemporary climate change has already changed the distribution and abundance of some of these species, and it has been challenging to predict such effects a priori. Using projected changes in oceanographic climate, we assessed vulnerability of marine forage species and dependent fishing vessels in the California Current. Based on expected changes in the mean and variability of temperature and chlorophyll concentrations, and species-specific sensitivity to these changes, we ranked the vulnerability of 15 forage species, all of which are fisheries targets. We used this measure of vulnerability of each stock as a proxy for the exposure of fishing vessels that target them to climate change. By coupling ecological vulnerability measure to estimates of social vulnerability—stemming from the financial dependence of fishing vessels on each stock and the potential for the vessels to adapt by targeting alternative stocks—we provide an integrated assessment of how climate change may differentially affect fishing vessels that target forage species.