WASHINGTON (CN) – The U.S. Fish and Wildlife Service has listed two Southern Florida butterflies as endangered under the Endangered Species Act. The agency also designated more than 22,000 acres of critical habitat for the Florida leafwing and Bartram”s scrub-hairstreak in a separate action.
Once common, both butterflies are now found only in and around the Everglades National Park (ENP), which spans Dade, Monroe and Collier counties in south Florida. The leafwing is only found within the park, while the hairstreak is found mostly in the ENP and in Big Pine Key outside the park, and in the National Key Deer Refuge in Monroe County, with sporadic reports of strays in three other Florida counties.
The twin actions released on Tuesday are part of a five-year court-approved work plan to reduce the backlog of listing candidates. The work plan resulted from a 2011 court settlement between the USFWS and the Center for Biological Diversity (CBD), one of the agency”s most frequent litigants.
The two butterflies were first placed on a listing candidate list in 1984, but further action stalled due to lack of sufficient information, according to last year”s proposed listing action.
The butterflies have lost habitat due to development and fire suppression activities such as mechanical clearing and controlled burns. They also face severe threats from pesticide use for mosquito control, poaching from collectors, predation by non-native species, disease, and now climate change challenges such as worsening tropical storms and the encroachment of rising sea-levels, the agency said.
“The best-case scenario projections for sea-level rise at Big Pine Key are for a rise of 7 inches, which would flood an estimated 34 percent of the island. The worst-case scenario projection is for 4.6 feet, which would put an astounding 96 percent of the Key underwater,” according to the CBD”s statement in response to the actions [emphasis in original].
The two butterflies share the pineland croton as a host plant, but look very different from each other. The leafwing resembles a dead brown leaf when its wings are closed, while the hairstreak is grey, with white and orange markings.
The critical habitat for both butterflies consists of roughly 80-85 percent federal land and 3-5 percent state land, with the rest as private or other lands, the agency said.
According to the agency”s press release, critical habitat designation does not establish a refuge or conservation area. Private landowner activities would only be affected if they are authorized, funded or carried out by a federal agency. “Designating critical habitat informs landowners and the public of the specific areas that are important to the conservation of the species and is required under the law. Identifying this habitat also helps focus the conservation efforts of other conservation partners, such as state and local governments, non-governmental organizations, and individuals,” the agency said.
The final listing action and the critical habitat designation are both effective Sept. 11.’