Document Type
Thesis
Date of Award
12-15-2023
Degree Name
Master of Science (MS)
Department
Biology
First Advisor
Daniel A Soluk
Abstract
In the age of the Anthropocene, wildlife is impacted by the presence of humans in both positive and negative ways. Many humans desire to conserve wildlife and the associated resources that come with it, while simultaneously the ever-expanding human population demands the land, food, and water resources, as well as other materials sourced from wildlife. Insects, a diverse and necessary group of animals are no exception to the impacts currently being experienced by wildlife. Because of this, some species are threatened or endangered, and human intervention is necessary. The federally endangered Hine’s Emerald dragonfly (Somatochlora hineana) is receiving intervention to augment wild populations via a captive rearing program based primarily at the University of South Dakota, using an approach known as headstarting. In the program, eggs are wild collected from adults in native habitat and brought to a laboratory setting until they are teneral adults, at which time they are released back into the area from which they were sourced. By diminishing potential sources of mortality that newly hatched larvae experience (e.g., competition, predation, and access to adequate prey resources), we increase survivorship, and the number of Hine’s emerald dragonflies introduced back into their native habitat. Laboratory experiments in microcosms evaluated the role of density and detrital community in growth and survivorship of hatchlings. Microbenthic community samples were collected in productive S. hineana habitat and contrasted with samples collected from microcosms. Results indicate that microbenthic communities from natural habitat were more abundant than laboratory microcosms. Density and components of the microbenthic community, such as Amphipoda and edible prey types, negatively and positively impact survivorship and growth of larvae in microcosms. These findings demonstrate the importance of evaluation of captive rearing protocol in efforts to conserve a species.
Keywords
captive rearing, conservation, dragonfly, headstarting, Odonata
Number of Pages
87
Publisher
University Of South Dakota
Recommended Citation
Morris, Lauren Michelle, "DON’T PUT ALL YOUR EGGS IN ONE BASKET: INCREASING SURVIVORSHIP IN A HEADSTARTING PROGRAM FOR THE ENDANGERED HINE’S EMERALD DRAGONFLY (SOMATOCHLORA HINEANA)" (2023). Dissertations and Theses. 198.
https://red.library.usd.edu/diss-thesis/198