St. Francis Satyr Monitoring & Studies (Neonympha mitchellii francisci)
Current Status: Federally Endangered
Biology and Ecology
The Saint Francis' satyr is a newly designated subspecies, and little is known of its life-history. The satyr probably lays its eggs on a larval host plant, or a plant in close proximity to its host plant. It may also lay its eggs on the litter or beneath the under surface of leaf blades close to the ground. Two broods are produced annually. The early summer brood probably completes its larval development in less than 80 days and pupation takes up to two weeks. The second brood most likely over winters in one of the late larval instars. Extensive feeding and growth resume in the spring before pupation takes place. The natural host plant is unknown, but it is suspected that sedges (Cyperaceae) or grasses (Poaceae) play an important role in the life cycle of the satyr.
Saint Francis' Satyr habitat
consists primarily of open wet meadows, interspersed with woody stems, and
dominated by a high diversity of sedges (Carex spp.) and other wetland
graminoids. In the North Carolina sandhills, such meadows are often
relicts of abandoned beaver impoundments. Other wetland habitat types may
be suitable habitat, but specific habitat requirements for this species
different life cycles is poorly understood. The butterfly occurs in
several natural plant communities to include coastal plain semi-permanent
impoundment-bog variant, coastal plain small stream swamp-canebrake variant,
Sandhills seep-bog variant, and streamhead pocosin-canebrake variant. It
appears beavers and frequent fires play an important role in habitat development
and maintenance. Larger pitcher plant bogs may be breeding sites based on
numbers of butterflies observed, compared to smaller, linear shaped pocosins
which appear to be dispersal pathways. Fort Bragg is involved in research
activities to learn more of this species' life history requirements.
Status and Distribution
The Saint Francis' Satyr is one of the rarest and least known American butterflies. Currently, it is only known to exist on Fort Bragg, comprising 19 known sites in one metapopulation. This extremely small geographic range encompasses only a few square miles. It is disjunct over 400 miles (640 km) south of the nearest historic locality of its nominate subspecies, N. m. mitchellii. Approximately 80 percent of the known colonies occur in the impact areas.
N. m. mitchellii was listed as endangered under the emergency listing provision of the Endangered Species Act (ESA), May 20, 1992. In the September 11, 1991 Federal Register, the Service proposed to give this butterfly long-term protection as endangered and subsequently did in 1992. However, the Saint Francis' satyr was not included as part of the listing because its status had not been as thoroughly documented as its northern cousin. The only known population at the time was thought to have been extinct. Rediscovered in 1992 as part of a USFWS funded survey, it was emergency listed as endangered, due to heavy collecting pressure, on April 18, 1994. This rule implemented federal protection for 240 days. Federal listing as endangered became effective January 26, 1995. The recovery plan for this species was approved in 1996.