Hannah J. Broadley

Hannah J. Broadley Headshot

PhD Candidate

B.S., Bates College, May 2010

M.S. Umass Amherst, Febuary 2016

Advisor: Joseph S. Elkinton

Research Interests

I am interested in population dynamics of invasive insects. I study the role of natural enemies in explaining why some insect populations outbreak (experience sudden population growth) while others do not or rarely do. As a major component of this work, I explore the theory and application of biological control in managing invasive insects. I am particularly interested in the interchange between natural enemies (predators, parasites, and pathogens) between native and introduced species and their population-level effects.  My current research is on winter moth, an invasive inchworm introduced to the Boston area in the 1990s that has since caused widespread defoliation. With the aim of better managing winter moth, I seek to understand the role of natural enemies and environmental constraints on winter moth and its native sister-species, Bruce spanworm. 


Winter moth caterpillars (photo credit: Rich Hennessy)

Pimpla aequalis, one of the native parasitoids affecting winter moth (photo credit: Taina Litwak)

Collecting winter moth caterpillars 2018 (photo credit: Joe Elkinton)


Prior research: My earlier research was with Dr. Celia Chen (Dartmouth College, Toxic Metals Superfund Research Program) studying the fate and effects of metal contaminants, mainly methymercury, in aquatic food webs both in freshwater and estuarine ecosystems.  

Sampling from Callahan Mine, Brooksville, ME ( photo credit: Kate Buckman)



Current research:

Broadley, H.J., J.S. Elkinton, R. Kula, G.J. Boettner, B. Griffin, and J.C. Andersen. Recruitment of native ichneumonid wasps to populations of the invasive winter moth, Operophtera brumata L., in the northeast U.S. In Prep. 

Donahue, K., H.J. Broadley, J.S. Elkinton, J.P. Burand, W. Huang, and J.C. Andersen. Using the SSU, ITS, and Ribosomal DNA Operon Arrangement to Characterize Two Microsporidia Infecting Bruce spanworm, Operophtera bruceata (Lepidoptera: Geometridae). Journal of Eukaryotic Microbiology. In Review.

Broadley, H.J., E.A. Kelly, J.S. Elkinton, R. Kula, and G.J. Boettner. 2018. Identification and impact of hyperparasitoids and predators affecting Cyzenis albicans (Tachinidae), a recently introduced biological control agent of winter moth (Operophtera brumata, L.) in the northeastern U.S.A. Biological Control, 121:99-108.

Broadley, H.J., M. Boucher, J.P. Burand, and J.S. Elkinton. 2016. The phylogenetic relationship and cross-infection of nucleopolyhedroviruses between the invasive winter moth (Operophtera brumata) and its native congener, Bruce spanworm (O. bruceata).  Journal of Invertebrate Pathology, 143:61-68.

Havill, N.P., J.S. Elkinton, J.C. Andersen, S.B. Hagen, H.J. Broadley, G.J. Boettner, A. Caccone. 2016. Asymmetric hybridization between non-native winter moth, Operophtera brumata (Lepidoptera: Geometridae), and native Bruce spanworm, O. bruceata, in the northeastern United States, assessed with novel microsatellites and SNPs. Bulletin of Entomological Research. DOI:10.1017/S0007485316000857

Pepi, A.A., H.J. Broadley, and J.S. Elkinton. Density-dependent effects of larval dispersal mediated by host plant quality on population of an invasive insect. 2016. Oecologia, 182:499 – 509. DOI: 10.1007/s00442-016-3689-z


Prior research:

Buckman, K.L., V.F. Taylor, H.J. Broadley, D. Hocking, P. Balcom, R. Mason, K. Nislow, and C.Y. Chen. 2017. Methylmercury bioaccumulation in an urban estuary: Delaware River USA. Estuaries and Coasts. DOI 10.1007/s12237-017-0232-3. 

Chaves-Ulloa, R., B.W. Taylor, H.J. Broadley, K.L. Cottingham, N.A. Baer, K.C. Weathers, H.A. Ewing, C.Y. Chen. 2016. Dissolved organic carbon modulates mercury concentrations in insect subsidies from streams to terrestrial consumers. Ecological Applications, 26(6):1771-1784. DOI:10.1890/15-0025.1

Buckman, K.L., M. Marvin-DiPasquale, V.F. Taylor, A. Chalmers, H.J. Broadley, J. Agee, B.P. Jackson, C.Y. Chen. 2015. Influence of a chlor-alkali superfund site on mercury bioaccumulation in periphyton and low-trophic level fauna.  Environmental Toxicology. DOI: 10.1002/etc.2964

Broadley, H.J., K.L. Buckman, D.M. Bugge, and C.Y. Chen. 2013. Spatial variability of metal  bioaccumulation in estuarine killifish (Fundulus heteroclitus) at the Callahan mine superfund site, Brooksville, ME. Archives of Environmental Contamination and Toxicology, 65:765–78.