This U.S. industry comprises establishments primarily engaged in one or more of the following: (1) eviscerating fresh fish by removing heads, fins, scales, bones, and entrails; (2) shucking and packing fresh shellfish; (3) manufacturing frozen seafood; and (4) processing fresh and frozen marine fats and oils. Cross-References. Establishments primarily engaged in canning and curing seafood are classified in U.S. Industry 311711, Seafood Canning.