After Hurricane Andrew ripped through South Florida in 1992, the already-scarce Miami blue butterfly almost went extinct: No one recorded a single sighting for years. Finally, in 1999, a cheer went up among butterfly enthusiasts when a photographer discovered 35 specimens in Bahia Honda State Park, which then housed the only wild population of Miami blues — but from which all known butterflies once again disappeared in 2010. This leaves only a few scattered individuals in another population in the Marquesas Keys in Key West National Wildlife Refuge. Despite captive-breeding and reintroduction efforts, this sun-loving coastal butterfly, once common throughout South Florida, is now one of the rarest insect species in North America.

The Miami blue experienced its first major setbacks in the 1980s, when coastal development exploded and Florida's war on mosquitoes dispersed toxic chemicals throughout the butterfly's range. In 1984 the butterfly became a candidate for federal listing. Owing to the efforts of the North American Butterfly Association, the species was declared endangered in the state of Florida in 2003. And due to a landmark 2011 agreement with the Center to push 757 species toward protection, the U.S. Fish and Wildlife Service has put the butterfly on the endangered species list.

But that protection was hard-won: In reluctant acknowledgment of the Miami blue's severe population decline and increasing harm from known threats, the Service proposed — but didn't finalize — emergency listing several times between 2000 and 2004. In 2001, the Service came to an agreement with the Center and other groups to expedite protection of 29 species, including the Miami blue, under the Act. But instead of granting the butterfly its rightful endangered status, the agency declared in 2005 that while the butterfly did merit protection, lack of funding prevented measures from being taken — and the species was again deemed a “candidate” and condemned to the “warranted but precluded” list. The Center challenged this determination with a notice of intent to sue in the same year, and we also filed suit to earn prompt protections for every one of the hundreds of species on the candidate list. When the butterfly was discovered missing from Bahia Honda State Park, in 2011 we filed an emergency petition to list the butterfly as endangered — and filed another notice of intent to sue when that petition was denied.