Endangered and Threatened Wildlife and Plants - Elfin-woods Warbler (US Fish and Wildlife Service Regulation) (FWS) (2018 Edition) The Law Library presents the complete text of the Endangered and Threatened Wildlife and Plants - Elfin-woods Warbler (US Fish and Wildlife Service Regulation) (FWS) (2018 Edition). Updated as of May 29, 2018 We, the U.S. Fish and Wildlife Service (Service), determine threatened species status under the Endangered Species Act (Act), as amended, for the elfin-woods warbler (Setophaga angelae), a bird species in Puerto Rico. This rule will add this species to the List of Endangered and Threatened Wildlife. We are also adopting a rule under the authority of section 4(d) of the Act (a "4(d) rule") that is necessary and advisable to provide for the conservation of the elfin-woods warbler. This book contains: - The complete text of the Endangered and Threatened Wildlife and Plants - Elfin-woods Warbler (US Fish and Wildlife Service Regulation) (FWS) (2018 Edition) - A table of contents with the page number of each section