Listing Status
- Federal Status: Endangered
- FL Status: Federally-designated Endangered
- FNAI Ranks: G4T1/S1 (Globally: Apparently Secure, Sub Sp. Critically Imperiled/ State: Critically Imperiled)
- IUCN Status: None
Appearance
Schaus’ swallowtail is a large black butterfly that can have a forewing length of up to 2.3 inches (5.8 centimeters). This species has contrasting white or yellow markings across the forewing, and a series of yellow blotches that continues along the forewing to the hind wing. It also has a black “tail” with yellow edging, and an orange patch on the underside of the hind wing (Florida Natural Areas Inventory 2001).
Behavior
The diet of Schaus’ swallowtail primarily consists of guava nectar, wild tamarind, and cheese shrubs (The Butterfly Conservation Initiative, n.d.).
Males begin courting by cruising around the tops (canopy) of trees in search of receptive females (Montana State University, n.d.). After mating, the female lays eggs singly on the leaves of wild lime (Zanthoxylum fagara) and sea torchwood (Amyris elemifera). Schaus’ swallowtails produce one generation annually between the months of April and July (Daniels 2007). Newly hatched caterpillars feed on young blossoms and leaves (Montana State University, n.d.). The emergence of adult butterflies depends on the beginning of the rainy season in Florida, as the pupae can remain dormant for over a year if the required weather conditions do not exist (Daniels 2007).
Habitat
Schaus’ swallowtail inhabits tropical hardwood hammocks in Key Largo and the islands in Biscayne National Park that support the species primary habitat (Florida Natural Areas Inventory 2001).
Threats
The Schaus’ swallowtail population faces environmental threats in its limited range. Weather conditions such as droughts and hurricanes also threaten the Schaus’ swallowtail. Droughts prevent the pupae from emerging out of dormant stage into adults. Due to its limited range in the Florida Keys, a strong hurricane could wipe out the population. In 1992, Hurricane Andrew nearly caused the extinction of the species with only 73 individuals surviving the storm (U.S. Fish & Wildlife Service, n.d.). Inbreeding threatens Schaus’ swallowtail because it causes genetic diversity to be lost within the species, thus limiting the ability to adapt to changing environments (Daniels 2007). Other threats include habitat loss due to development and pesticide spraying for mosquito control.
Conservation and Management
Schaus’ swallowtail butterfly is protected as an Endangered species by the Federal Endangered Species Act and as a Federally-designated Endangered species by Florida’s Endangered and Threatened Species Rule.