Sec. 13. The department shall use the fund, in accordance with this chapter, to acquire natural areas by purchase, gift, or reimbursement to complete the state nature preserve system. A site may not be acquired as part of the campaign that has not been approved for registry. In addition, in making the determination as to whether particular sites of natural interest will be acquired as part of the campaign, the department shall consider whether the site:
(1) is a relatively undisturbed example of a native ecological community that is uncommon;
(2) is habitat for native plant or animal species classified as endangered or threatened by the division of nature preserves and the Indiana heritage program;
(3) is a superlative example of a native ecological community; or
(4) if acquired, would significantly enhance efforts to protect natural systems or features in an existing nature preserve or campaign acquisition.