; (ii) whether the implementation of the standardized methodology developed under paragraph (1) and the template developed under paragraph (2)(A) has impacted efforts by States, units of local government, and other entities— (I) to reduce the number of wildlife-vehicle collisions; and (II) to improve habitat connectivity; (iii) the degree of the impact described in clause (ii); and (iv) the recommendations of the Secretary, including recommendations for further study aimed at reducing motorist collisions involving wildlife and improving habitat connectivity for terrestrial and aquatic species on the National Highway System, if any. (c) National threshold guidance The Secretary of Transportation shall— (1) establish guidance, to be carried out by States on a voluntary basis, that contains a threshold for determining whether a highway shall be evaluated for potential mitigation measures to reduce wildlife-vehicle collisions and increase habitat connectivity for terrestrial and aquatic species, taking into consideration— (A) the number of wildlife-vehicle collisions on the highway that pose a human safety risk; (B) highway-related mortality and effects of traffic on the highway on— (i) species listed as endangered species or threatened species under the Endangered Species Act of 1973 ( 16 U.S.C. 1531 et seq.); (ii) species identified by a State as species of greatest conservation need; (iii) species identified in State wildlife plans; and (iv) medium and small terrestrial and aquatic species