Top-down and Bottom-up Approaches to Understanding the Fate of the Federally Endangered Schaus’ Swallowtail Butterfly (Heraclides aristodemus ponceanus)

• Main Author: Clayborn, Jaeson T.
• Format: Others
• Published: FIU Digital Commons 2017
• Subjects: biology; Biology; Botany; Entomology; Life Sciences; Outdoor Education
• Online Access: https://digitalcommons.fiu.edu/etd/3698; https://digitalcommons.fiu.edu/cgi/viewcontent.cgi?article=4786&context=etd

The federally endangered Schaus’ swallowtail butterfly (Heraclides aristodemus ponceanus) populations have declined precipitously over the years. Despite tremendous efforts to augment the numbers of this butterfly through captive-bred releases and habitat enhancements, it remains imperiled and federally endangered. The dissertation’s objectives were: 1) to restore dry forest habitat in Biscayne National Park (BNP) for Schaus’ swallowtails; 2) to assess host plant (torchwood and wild lime) survivorship and growth in the restoration sites (BNP) and project dry forest habitat loss because of imminent sea level rise (SLR); 3) to quantify ant activity and record predator-prey interactions against Heraclides caterpillars in dry forest habitat in BNP; and 4) to implement a south Florida butterfly conservation curriculum unit at schools in Miami-Dade County, and evaluate students’ gained knowledge and attitudes toward south Florida environments, insects and butterflies, and conservation. More than 3,200 native plants were planted in restoration sites in BNP. Eighty-five percent were torchwood, the primary host plant for Schaus’ swallowtails. Canopy cover, ground elevation, and relative soil depth had a negligible effect on torchwood survivorship; however, ground elevation had a strong effect on growth. Dry forest habitat in Key Largo will succumb less quickly to SLR than in BNP because of higher elevation. Pseudomyrmex gracilis was the most common ant on Schaus’ swallowtail host plants, which aggressively attacked early instar caterpillars (86.7%). The predator exclusion experiment demonstrated that early instar caterpillars were least likely to survive when exposed to crawling and non-crawling predators. The controlled-experiment at three schools revealed the integrated insect curriculum unit significantly increased students’ content knowledge in the experimental groups. Pre- and post-surveys revealed students demonstrated favorable interest in animals and plants and were advocates for environmental stewardship; however, they reported less interest in insects. Service-learning and inquiry-based activities in dry forests, gardens, homes, and schools make imperiled insects and ecosystems salient, thus leading to potential advocacy for them. A better understanding of Schaus’ swallowtail dynamics in the Florida Keys presents an opportunity to preserve its existence and thwart extinction.