29 CFR §784.107

It is also necessary to the application of the exemptions that the operation of which the employee's work is a part be performed on the marine products named in the Act. Thus the operations described in section 13(a)(5) must be performed with respect to “any kind of fish, shellfish, crustacea, sponges, seaweeds, or other aquatic forms of animal and vegetable life.” The operations enumerated in section 13(b)(4) must be performed with respect to “any kind of fish, shellfish, or other aquatic forms of animal or vegetable life, or any byproduct thereof”. Work performed on products which do not fall within these descriptions is not within the exemptions (Fleming v. Hawkeye Pearl Button Co., 113 F. 2d 52; Mitchell v. Trade Winds, Inc., 289 F. 2d 278; Walling v. Haden, 153 F. 2d 196).