Harbor Porpoise Bycatch: ITQs or Time/Area Closures in the New England Gillnet Fishery

The implications of individual transferable quotas (ITQs) for reducing harbor porpoise bycatch in a multi-species fishery are investigated. Our intra-year bioeconomic model incorporates spatial and temporal patterns of abundance and harvest rates of commercial fish species and porpoise. Results indicate that porpoise ITQs, when compared to closures, are more profitable than closures, and distribute effort and profit reductions more evenly across seasons and areas. Price estimates for a unit of porpoise quota ranges from $1,395 to $5,782, for total allowable catches ranging from 951 to 209 porpoise, respectively. Total annual willingness to pay for porpoise quota is approximately $1.25 million.