Hannah J Broadley

Hannah J Broadley
United States Department of Agriculture | USDA · APHIS Plant Protection and Quarantine (PPQ) Science & Technology

Doctor of Philosophy

About

29
Publications
3,231
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170
Citations
Introduction
I am a Biological Scientist/Entomologist with the USDA APHIS Plant Protection and Quarantine Science & Technology. Currently, my main research is on developing biological control methods for spotted lanternfly and determining the distribution and natural enemy complex of the roseau cane scale in Asia. My dissertation research was on the population dynamics and biological control of the invasive insect winter moth. I also collaborate on gypsy moth and emerald ash borer research.
Additional affiliations
September 2018 - February 2020
University of Massachusetts Amherst
Position
  • PostDoc Position
March 2013 - August 2018
University of Massachusetts Amherst
Position
  • PhD Student
June 2010 - March 2013
Dartmouth College
Position
  • Technician

Publications

Publications (29)
Article
Specialized natural enemies have long been used to implement biological control of invasive insects. While research tracking populations following biological control introductions has traditionally focused on the impact of the introduced agent, recent studies and reviews reflect an appreciation of the complex interactions of the introduced speciali...
Article
Full-text available
The recent decline of Phragmites australis stands in the Mississippi River Delta is due, in part, to damage from herbivory by the non-native roseau cane scale, Nipponaclerda biwakoensis. In Louisiana, P. australis communities, known locally as roseau cane, protect the marsh ecosystem from erosion and storm-related impacts, stabilize shipping channe...
Article
Full-text available
Roseau cane (Phragmites australis (Cav). Trin. ex Steud.) is the dominant plant species of the Mississippi River Delta in Louisiana, USA, and protects the coastline from erosion and storm‐related impacts, maintaining shipping channels and oil infrastructure. Widespread dieback and thinning of P. australis were noted in the Mississippi River Delta i...
Article
Full-text available
Winter moth, Operophtera brumata, native to Europe, invaded the northeastern United States in the late 1990s, where it caused widespread defoliation of forests and shade trees ranging from 2,266 to 36,360 ha per year between 2003 and 2015 in Massachusetts. In 2005, we initiated a biological control effort based on the specialist tachinid parasitoid...
Article
Full-text available
An invasive population of spotted lanternfly (SLF), Lycorma delicatula White, was first noted in North America in Pennsylvania in 2014, and by September 2020 populations had spread to six additional states. To develop a biocontrol program to aid in the management of the pest, exploratory surveys for SLF natural enemies in its native range were carr...
Article
Full-text available
To support efforts to manage and contain spotted lanternfly (SLF), Lycorma delicatula White (Hemiptera: Fulgoridae), research is being conducted to develop classical biological control methods. To date, two potential biocontrol agents from China have been identified: an egg parasitoid, Anastatus orientalis, and a nymphal parasitoid, Dryinus sinicus...
Article
Full-text available
Here we compare the environmental niche of a highly polyphagous forest Lepidoptera species, the winter moth ( Operophtera brumata ), in its native and invaded range. During the last 90 years, this European tree folivore has invaded North America in at least three regions and exhibited eruptive population behavior in both its native and invaded rang...
Article
Full-text available
In North America the invasive winter moth (Operopthera brumata) has caused defoliation in forest and fruit crop systems in British Columbia, Nova Scotia, Oregon, and in the northeastern United States (the “Northeast”). In the Northeast, it was previously shown that hybridization is occurring with a native congener, Bruce spanworm (O. bruceata)—a sp...
Article
Full-text available
The spotted lanternfly, Lycorma delicatula White (1845) (Hemiptera: Fulgoridae), is an invasive insect that was first reported in North America in Berks County, Pennsylvania, in 2014. It is a polyphagous phloem feeder that attacks over 70 plant species, threatening the agricultural, lumber, and ornamental industries of North America. Infestations o...
Article
Full-text available
The bioaccumulation of the neurotoxin methylmercury (MeHg) in freshwater ecosystems is thought to be mediated by both water chemistry (e.g., dissolved organic carbon [DOC] and dissolved mercury [Hg]) and diet (e.g., trophic position and diet composition). Hg in small streams is of particular interest given their role as a link between terrestrial a...
Article
Full-text available
We collected data on mortality of late-instar gypsy moth, Lymantria dispar (L.), from outbreak populations over 4 wk in June 2017 at 10 sites in the New England region of the United States, along with estimated rainfall at these sites. Deposition of airborne conidia of the fungal pathogen, Entomophaga maimaiga Humber, Shimazu & R.S. Soper, was meas...
Article
Full-text available
Ecological communities may be resistant to invasive species through a combination of top-down and bottom-up mechanisms, including predation, competition, parasitism, and disease. In particular, natural enemies that cross over from native species to use newly introduced non-native species as hosts can influence invasive species population dynamics a...
Article
Full-text available
Research pertaining to the two closely‐related microsporidian genera Nosema and Vairimorpha is hindered by inconsistencies in species differentiation within and between the two clades. One proposal to better delimit these genera is to restructure the Nosema around a “True Nosema” clade, consisting of species that share a characteristic reversed rib...
Article
The success or failure of an introduced biological control agent may depend on its rate of mortality from disease, predation, and hyperparasitism. Cyzenis albicans Fallén (Diptera: Tachinidae) was introduced to the northeastern U.S. as a biocontrol agent of the invasive species winter moth, Operophtera brumata L. (Lepidoptera: Geometridae). This st...
Article
Full-text available
There was a coding error in the original paper resulting in incorrect model parameter estimates and in some cases incorrect model conclusions. The error was the specification of logistic models (using the glm and glmer functions) in R as cbind (survived, total) instead of cbind (survived, dead). The differences between the originally published and...
Conference Paper
Natural enemies that cross over from related native species to inasive species mediate invasions in complex ways. In the northeastern United States, the winter moth (Operophtera brumata) is an invasive, forest pest. While biocontrol show promising results, success likely depends on additional mortality from native, natural enemies. However, little...
Conference Paper
The exchange of pathogens between populations or related species can mediate insect invasions in complex ways, either suppressing or stimulating population growth. We evaluated sources of nucleopolyhedroviruses (NPV) in winter moth Operophtera brumata L. (Lepidoptera: Geometridae). Invasive populations of this destructive insect from Europe may be...
Article
Spatial variation in mercury (Hg) and methylmercury (MeHg) bioaccumulation in urban coastal watersheds reflects complex interactions between Hg sources, land use, and environmental gradients. We examined MeHg concentrations in fauna from the Delaware River estuary, and related these measurements to environmental parameters and human impacts on the...
Chapter
This proceedings contains papers dealing with issues affecting biological control, particularly pertaining to the use of parasitoids and predators as biological control agents. This includes all approaches to biological control: conservation, augmentation, and importation of natural enemy species for the control of arthropod targets, as well as oth...
Chapter
This proceedings contains papers dealing with issues affecting biological control, particularly pertaining to the use of parasitoids and predators as biological control agents. This includes all approaches to biological control: conservation, augmentation, and importation of natural enemy species for the control of arthropod targets, as well as oth...
Article
Disease can affect biological invasions by acting as either a synergist or antagonist. Disease-mediated invasions have important implications for understanding the spread of invasive insects, which cost billions of dollars in damages annually. One such non-native, destructive insect is the winter moth, Operophtera brumata L. (Lepidoptera: Geometrid...
Article
The European winter moth, Operophtera brumata , is a non-native pest in the Northeastern USA causing defoliation of forest trees and crops such as apples and blueberries. This species is known to hybridize with O. bruceata , the Bruce spanworm, a native species across North America, although it is not known if there are hybrid generations beyond F1...
Article
Full-text available
The success of invasive species is often thought to be due to release from natural enemies. This hypothesis assumes that species are regulated by top-down forces in their native range and are likely to be regulated by bottom-up forces in the invasive range. Neither of these assumptions has been consistently supported with insects, a group which inc...
Article
Mercury (Hg) concentrations in aquatic environments have increased globally, exposing consumers of aquatic organisms to high Hg levels. For both aquatic and terrestrial consumers, exposure to Hg depends on their food sources as well as environmental factors influencing Hg bioavailability. The majority of the research on the transfer of methylmercur...
Conference Paper
Bruce spanworm, Operophtera bruceata, and winter moth, Operophtera brumata, are closely related geometrids, can hybridize, and may share natural enemies. In the northeastern US, Bruce spanworm populations mostly remain at low density and rarely experiences outbreaks. Outbreaks of this species are rare and short-lived. In contrast, the introduced wi...
Article
In Berlin, NH, the Androscoggin River flows adjacent to a former chlor-alkali facility that is a US EPA Superfund site and source of mercury (Hg) to the river. A study was conducted to determine the fate and bioaccumulation of methylmercury (MeHg) to lower trophic-level taxa in the river. Surface sediment directly adjacent to the source showed sign...
Conference Paper
Winter moth (Operophtera brumata, L.) is an invasive, polyphagous geometrid that has caused regular defoliation of deciduous trees in Massachusetts since its introduction in the 1990s. Winter moth population ecology has been well studied in its native range in Europe, as well as from two prior, accidental introductions into North America: to Nova S...
Conference Paper
In New England, winter moth (Operophtera brumata) is a non-native insect and for the last 15 years has caused widespread defoliation of deciduous trees A tachinid parasitoid (Cyzenis albicans) has been introduced to control the outbreak. The fly has now been established at 11 sites with parasitism levels of 30-40%. However, densities of winter moth...
Article
Full-text available
The former Callahan Mine Site in Brooksville, ME, is an open-pit, hardrock mine site in an intertidal system, thus providing a unique opportunity to evaluate how metal-enriched sediments and overlying water impact estuarine food webs. Copper, zinc, cadmium, and lead concentrations in sediment, whole water, and Atlantic killifish (Fundulus heterocli...

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Projects

Projects (3)
Project
We are completing research to to support the development of management options for the scale insect Roseau cane scale, Nipponaclerda biwakoensis (Hemiptera: Aclerdidae) in Louisiana, where it is an invasive pest on common reed (Phragmites australis). Recently there has been widespread dieback and thinning of the reed stands in the lower Mississippi River Delta. These diebacks coincide with heavy populations of the scale, which live on the stems and remove sap from the plant. Research toward evaluating the hosts, geographic range, and natural enemies of the scale in the introduced range in Louisiana and as well as the native range in Asia is needed.
Project
The spotted lanternfly (SLF, Lycorma delicatula) is a invasive insect recently detected in the eastern United States. It was discovered in Berks County Pennsylvania in 2014 and has since spread to additional counties and states. Given the eradication challenges, we are working to develop a biological control program against the spotted lanternfly. As the first step, potential classical biological control agents were identified through publications and previous work from South Korea and China. We now have ongoing research on the egg parasitoid Anastatus orientalis Yang (Hymenoptera: Eupelmidae) and a nymphal parastioid Dryinus sp. (Hymenoptera: Dryinidae).
Project
Invasive insects increasingly affect forested landscapes and have important ecological and economic impacts. This research focuses on population dynamics of winter moth (Operophtera brumata L.), an invasive pest in the northeastern United States. Native to Europe, this is the species’ fourth accidental introduction to North America. The Elkinton lab established the biological control agent Cyzenis albicans across the range of winter moth in the northeastern U.S. Prior research indicates that C. albicans’ ability to control winter moth likely depends on additional mortality from native (resident) natural enemies. This body of research evaluates the identity and role of natural enemies already present in North America (predators, parasitoids, and pathogens) on winter moth, the potential source of these natural enemies, and their interaction with C. albicans on the resulting winter moth population dynamics.