Because of the sensitivity of tuna fisheries to temperature, medium and long-term climate changes create potential challenges for future catch and fishery sustainability. Moreover, since many tuna fisheries operate on the high seas, individual actions by captains and fishermen are the primary method for mitigating damages from these environmental processes. An effective way to reduce damages from these environmental risks might be to provide harvesters with information about potential damages, allowing them to adapt to the risky processes by adopting behaviors that mitigate those risks. Using data from the North Pacific albacore fishery and Western and Central Pacific purse-seine tuna fishery, the Fellow will estimate the degree to which adaptation reduces damages from medium-term climate fluctuations caused by El Niño/Southern Oscillation (ENSO). He will, (1) estimate the extent that ENSO forecasts reduce fishery damages; (2) Calculate the value of forecasts; (3) Investigate the behavioral changes of fishermen in response to forecasts; and (4) Model whether behavior changes are a result of self-learning or forecasts. The project will ultimately shed light on how adaptation is achieved, the degree to which adaptation can reduce damages from environmental processes, and the potential for providing centralized climate information to engender adaptation.