Traditional productivity measures have been much less prevalent than other measures of economic and biological performance in fisheries economics. It has been increasingly recognized, however, that modeling and measuring fisheries' production relationships is central to understanding and ultimately correcting the repercussions of externalities and poorly designed regulations. We use a transformation function production model to estimate productivity and its components for the Bering Sea and Aleutian Islands pollock fishery. We recognize the roles of externalities from pollock harvesting by incorporating data on environmental conditions, bycatch, and biomass stock, and capture regulatory impacts through fishing strategy indicators and fixed effects. We find that the productive contributions and interactions of environmental conditions, bycatch, and fishing strategies are statistically significant, and that regulatory changes have had both direct and indirect impacts on catch patterns.