For the acquisition, including the location, examination, and survey, of suitable areas of land, water, or land and water, for use as migratory bird reservations, and necessary expenses incident thereto, and for the administration, maintenance, and development of such areas and other preserves, reservations, or breeding grounds frequented by migratory birds and under the administration of the Secretary of the Interior, including the construction of dams, dikes, ditches, flumes, spillways, buildings, and other necessary improvements, and for the elimination of the loss of migratory birds from alkali poisoning, oil pollution of waters, or other causes, for cooperation with local authorities in wildlife conservation, for investigations and publications relating to North American birds, for personal services, printing, engraving, and issuance of circulars, posters, and other necessary matter and for the enforcement of the provisions of this subchapter, there are hereby authorized to be appropriated, in addition to all other amounts authorized by law to be appropriated, $200,000 for the fiscal year ending June 30, 1940, and for each fiscal year thereafter. No part of any appropriation authorized by this section shall be used for payment of the salary, compensation, or expenses of any United States protector, except reservation protectors for the administration, maintenance and protection of such reservations and the birds thereon: Provided, That reservation protectors appointed under the provisions of this subchapter, shall be selected, when practicable, from qualified citizens of the State in which they are to be employed. The Secretary of the Interior is authorized and directed to make such expenditures and to employ such means, including personal services in the District of Columbia and elsewhere, as may be necessary to carry out the foregoing objects.