The main purpose of this legislation is to amend the Endangered Species Act of 1973. The goal is to ensure that species not native to the United States cannot be classified as endangered or threatened. Additionally, it aims to restrict certain types of financial assistance related to land acquisition. Key provisions of the legislation include a clear prohibition on listing nonnative species as endangered or threatened. This means that if a species is not originally from the U.S., it cannot be protected under this law.