Where any fish or any other thing of a perishable nature is seized as liable to forfeiture under paragraph 5 above, the person by whom it is seized may sell it, and the net proceeds of sale shall be liable to forfeiture in the same manner as the fish or other thing sold, and if and so far as not forfeited shall be paid on demand to the owner; but no person shall be subject to any liability on account of his neglect or failure to exercise the powers conferred on him by this paragraph.