Novel use of 14C bomb-pulse to measure
how many years saturniid moths spend as pupae

John Pickering1,2 and Alex Cherkinsky1
1-University of Georgia, Athens, Georgia, USA
2-Sam Houston State University, Huntsville, Texas, USA,

The 14th International Conference on Accelerator Mass Spectrometry, abstract 75763, 2017

There is anecdotal evidence that a broad array of holometabolous insects, ones that have metamorphosism with a pupal stage, exhibit "super diapause" in which some specimens spend multiple years as pupae before developing into adults. The four major insect orders are all known to have species capable of spending two or more years as pupae. Despite the potential importance of such "pupa banks" to affect insect population dynamics, virtually no research addresses how many years insects may diapause under natural conditions. Here we report the novel application of bomb-pulse to measure how long adult moths collected in the eastern United States and stored in museums remained as pupae. Our analysis focuses on the Saturniidae, a family which only feeds as larvae and never as adults. We compare the estimated date when each saturniid acquired 14C as a larva and when it was an adult, the difference being the time spent in pupal diapause. Our results suggest that Automeris io and Citheronia regalis both have multi-year diapause. Given our method's success, we now plan to analyze more specimens to measure how frequent super diapause is across natural populations and how it may be affected by geographic location and weather patterns.