Imperiled Butterflies: Schaus Swallowtail

About 150 butterfly species are found throughout Florida. 15 of those species are found only in extreme southern Florida and the Florida Keys. Continued expansion of urban development and widespread use of pesticides used to control mosquito populations have put many of these species in jeopardy.

This is part six of a multi-part series covering Florida’s imperiled butterflies.

Schaus Swallowtail

The Schaus Swallowtail (Heraclides aristodemus ponceanus) was first discovered at the turn of the last century in the Miami area and just 76 years later it was first listed as a threatened species. By 1984, the drastic reduction of this species’ habitat caused it to be upgraded to endangered. Once found from Miami south to Lower Matecumbe Key, this butterfly is now found only from Key Biscayne Park to northern Key Largo and Upper Matecumbe Key. The last Schaus Swallowtail was observed on the Florida mainland in 1924.

In 1992, Hurricane Andrew gravely impacted the remaining habitat of this butterfly and there were as few as several dozen Schaus Swallowtails left in the wild. A captive breeding and release program was undertaken and the species reached a high of 1,200 to 1,400 individuals in 1996 and 1997. In 1998, Hurricane Georges struck the areas where this population resided, followed by several years of drought. By 2002 the population was estimated to be about 190-230 adults in the wild.

The Schaus Swallowtail resides only in hardwood hammocks and their larvae feed on hop tree (Ptelea trifoliata) , torchwood (Amyris elemifera) and wild lime (Xanthoxylum fagara). Adult butterflies nectar on flowering plants such as guava, wild tamarind, and cheese shrub. Ongoing projects in the Florida Keys and Miami area seek to create new habitat for this species by planting larval hosts and adult nectar sources on private and public lands.

Currently, the Schaus Swallowtail has a conservation status of T1- Critically imperiled globally because of extreme rarity (5 or fewer occurrences, or very few remaining individuals), or because of some factor of its biology making it especially vulnerable to extinction. (Critically endangered throughout its range).