As soon as practicable after September 13, 1962, and following the acquisition by the Secretary of an acreage in the area described in section 
459c–1 of this title, that is in the opinion of the Secretary efficiently administrable to carry out the purposes of sections 
459c to 
459c–7 of this title, the Secretary shall establish Point Reyes National Seashore by the publication of notice thereof in the Federal Register.