161.25 County beach and shore preservation authority; board of county commissioners.—To carry out the beach and shore preservation program, the board of county commissioners of any county and its successors in office, as an ex officio duty, are hereby severally constituted as the beach and shore preservation authority for their county. In this capacity, any such board of county commissioners may at its own initiative take all necessary steps as soon as practicable and desirable to implement the provisions of this chapter.