All moneys in the Fisheries Loan Fund established under Section ¹ 742c of this title shall be invested by the Secretary of Commerce in obligations of the United States, except so much as shall be currently needed for loans or administrative expenses authorized under the Fisheries Loan Fund. All accrued proceeds from such investment shall be, subject to amounts provided in advance by appropriations, credited by the Secretary of the Treasury to the debt of the Secretary of Commerce incurred under section 53723 of title 46 in connection with fisheries financing under chapter 537 of title 46 for so long as such debt exists. All accrued proceeds from such investment, after such debt has been liquidated, shall be, subject to amounts provided in advance by appropriations, credited to the fisheries portion of the Federal Ship Financing Fund established under section 1102 of the Merchant Marine Act, 1936, as amended, and used for the fisheries purposes provided in chapter 537 of title 46.