VERO BEACH, Fla. - Two butterflies found only in South Florida have been added to the endangered species list.

The U.S. Fish and Wildlife Service announced Monday that it was listing the Florida leafwing and Bartram's scrub-hairstreak as endangered. It also is designating thousands of acres of critical habitat for both butterflies.

Both butterflies are found only in Miami-Dade and Monroe counties.

Federal officials blame the butterflies' decline on habitat destruction. Other factors include climate change, parasites and diseases, poaching, poor fire management and chemical pesticides used for mosquito control.

The habitat designation does not stop development, but it would require private landowners to obtain permits for construction and to carefully manage the land. Most of the designated habitat is in Everglades National Park or other federal lands, but some tracts are slated for development.