Brief update on development of a modified diet to support conservation of the Atala Hairstreak butterfly (Eumaeus atala) Elizabeth Braatz1 and Jamie Sincage2 1Technician, Disney’s Animals, Science and Environment 2Zoological Manager, Disney’s Animals, Science and Environment Disney’s Animals, Science and Environment Animal Programs Administration PO Box 10000, Lake Buena Vista, FL 32830, USA Introduction With deep black wings, ultramarine spots, and bright orange abdomens, the Atala butterfly was once a classic butterfly of Southeast Florida. Adult butterflies have highly distinctive coloration, and similarly, caterpillars are unique with their bright orange bodies and yellow spots. Atala caterpillars can only eat coontie cycads (Zamia integrifolia, synonym for Zamia pumila and Zamia floridana), although some accounts note they can eat Zamia erosa, a Puerto Rican variety of the plant (M. Feather, personal communication). If washed, the toxic coontie plant’s root can yield an edible, nutritious flour. This flour became very popular with European settlers. Consequently, by 1965 the once-numerous Atala became almost extinct due to habitat loss and coontie overharvesting (Daniels, 2003). At one point, it is believed that the entire butterfly population shrunk to a single colony along the coast of Miami (Levine, 2016). With the help of zoos and universities, conservation programs have been developed to return the Atala butterfly to Florida (Zoo Miami, 2017). Thanks to breeding and release efforts, combined with the increased use of coontie as a popular plant in local landscapes, the future for the Atala butterfly looks promising. Disney’s Animal Kingdom has embarked on a program to raise Atala butterflies, but also works to engage the public with nature by providing opportunities for guests staying at Disney’s Vero Beach Resort to release butterflies into a restored natural habitat. Organizations working on sustaining breeding butterfly populations are often challenged with finding year round availability of their host plants, and this project was no exception. Much progress was made thanks to previous work on Atala winter diets (Ardente et al., 2017). Discussions at round tables during the Invertebrates in Education and Conservation Conference (IECC) 2017 further aided our methodology, and by building off these learnings we developed a diet that can support a colony of Atala caterpillars (Ardente et al., 2017). Methods A full review of the methods are presented in Braatz, et al., In prep. In summary, we created a freeze-dried diet by collecting and saving fresh growth coontie during summer growing months. This fresh growth was stored and freeze-dried, and we crushed the freeze-dried plants into powder form. To reconstitute the powder, we added water. The water-powder paste was fed to caterpillars as their primary diet. Palatability 1 We pilot tested whether this diet was palatable to 11 young caterpillars. Caterpillars were housed together in a plastic tub, and we cleaned their containers and fed them daily. We housed the adult butterflies in flight cages supplied with food and a host plant, and we checked whether they produced viable eggs. Freeze-dried vs. Fresh Growth A group of twenty second-instar caterpillars were fed the freeze-dried diet until pupation. Another group of twenty second-instar caterpillars were fed fresh growth coontie until pupation. We tested whether there were any differences in pupation rates and ability to reproduce based on their diet. Results As reported in in Braatz, et al., In prep, the freeze dried diet was accepted by the eleven young caterpillars in the pilot group, resulting in 90.9% pupation success. Eighty percent of the twenty caterpillars fed a freeze-dried diet successfully pupated, while 75% of the caterpillars fed fresh growth coontie successfully pupated. Discussion We tested a freeze dried diet of fresh growth coontie that appears to be able to support a reproductively active colony of Atala butterfly (Braatz, et al., In prep). This new diet helps those rearing this butterfly in managed colonies to successfully provide a food source, allowing reproduction to continue throughout the year. Acknowledgements Our part in conserving the Atala butterfly wouldn’t be possible without our excellent partners, who have contributed significantly to the development and execution of this project. In addition to the coauthors listed in the Braatz et al. In prep, we would like to extend our sincere gratitude towards the following individuals and teams: Michelle N. Mark, Tayler Schwartz, Devin Beauchamp, and Rebekah Lindborg for completing vital data collection and husbandry tasks, Jennifer L. Rhodes and Erica E. Huffstodt for preparing food for hungry caterpillars over winter, Michele E. Rohrmann, William B. Broome, Michael P. English, and their Horticulture teams for making summer coontie harvests possible, Janet M. Wyatt, Debbie M. Mickler, Linda L. Holland, Heather Will-Brown, and their Horticulture Nursery teams for optimizing coontie plant management over the winter, Deborah J. Weber for her expertise and help with coontie assessments, and Benji Schwartz and Dr. Jaret C. Daniels for photographs. 2 References Ardente A, Sincage J, Gezon Z, Savage A, Valdes E. (2017). Development of an artificial diet to support conservation efforts of the Atala Hairstreak Butterfly (Eumaeus atala). Proceedings from IECC: 2017 Invertebrates in Education and Conservation Conference. Tucson, AZ. Braatz, E., Sincage, J., Gezon, Z., Ardente, A., Sullivan, K.E., Valdes, E.V., Savage, A., Livingston, S., (N.d.) Update on development of a modified diet to support conservation of the Atala hairstreak butterfly (Eumaeus atala). In prep. Daniels, J.C (2003). Butterflies of Florida field guide. Cambridge, MN: Adventure Publications, Inc. Levine, R. (22 March 2016). A nearly extinct butterfly makes a comeback in South Florida. Entomology Today. Retrieved from https://entomologytoday.org/2016/03/21/a-nearly- extinct-butterfly-makes-a-comeback-in-south-florida/ Zoo Miami. (2017). 2017 Conservation and Research Report. Retrieved from https://www.speakcdn.com/assets/2440/zoo_miami_conservation_and_research_annual_r eport_2017.pdf 3 .