Paula Henry, Ph.D.
Paula Henry is a research physiologist at the Patuxent Wildlife Research Center, Laurel Maryland. Her areas of research focus on sublethal and endocrine effects of environmental contaminant exposure on avian, amphibian and reptilian physiology and behaviors, and on anthropogenic factors affecting wildlife populations within estuarine and wetland habitats. Her work seeks to integrate laboratory, pen, and field studies for evaluating relative sensitivities of wildlife exposed to environmental pollutants including metals, pesticides, agricultural additives, and industrial chemicals. Paula lead a multi-year USGS field survey and research study investigating declining terrapin populations in the Chesapeake Bay watershed, and continues to monitor box turtles on the Patuxent Wildlife Refuge.as part of a historical and long term population study
- Ph.D. in Marine Estuarine Environmental Science(Endpoint measurements for endocrine disrupting contaminant effects on wildlife)
- M.S. in Zoology and Endocrinology (Effects of sublethal dietary levels of EPN (0-ethyl,0-4-nitrophenylphenylphosphonothioate) on growing mallard ducklings, Anas platyrhynchos), from the University of Maryland, College Park
- B.A. (Le matin apres la mescaline) from Reed College in Portland Oregon.
- USGS Special Act Service Award, Time off Awards and Star Awards: 1998, 2002, 2004, 2005, 2006, 2007, 2012, 2013
- Scientific Achievement Award: Coauthor on Publication of Significance 1997.
- NBS Certificate of Appreciation, Quality Service Award, and Performance Award. 1994, 1995, 1996
- Chesapeake and Potomac Regional Chapter, SETAC. Graduate Student Research Award 1996.
- USFWS Special Achievement Award and Quality Performance Award. 1989, 1991
- USUHS – DoD Certificate of Outstanding Performance. 1986
- USFWS and US EPA Graduate Student Research Assistantship 1982.
- Interagency Coordinating Committee on the Validation of Alternative Methods, DOI alternate: 2015
- DOI One Health, USGS Contaminant representative: 2015
- SETAC Chesapeake Potomac Regional Committee, Member: 1996-1998; 2000-present; Board of Directors 2012-2015; Vice-President 2015-present.
- Diamondback Terrapin Working Group. Member: 2004-present; Chair for the Mid Atlantic Region: 2004-2007.
- NE Partners in Amphibians and Reptiles Conservation Task Team, Amphibian and Reptile Diseases (Rana virus), Member: 2011-present.
- Inter County Connector (ICC) Box Turtle Advisory Committee. Member: 2007-2009.
- Strategic Environmental Research Program /Environmental Security Technology Certification Program (SERP/ESTP): USGS Science Representative: 2007-2008.
- USGS PWRC Animal Care and Use Committee. Research representative: 1991-1993;2003-2005; Chair: 2005-2008.
Science and Products
The Challenge: Neonicotinoid pesticides act as agonists of nicotinic acetylcholine receptors (nAChRs) and are designed to be lethal to insects while theoretically posing little to no threat to vertebrates. The perceived safety of neonicotinoids has led to a sharp increase in their use in the United States and globally, since they were first introduced in 1994. The use of the neonicotinoid imidacloprid in the United States has increased 166% since 2009, from 0.75 to roughly 2 million pounds, and its use as seed treatment represents approximately 56% of total annual usage. Although neonicotinoids are designed to be selectively toxic to invertebrates, effects on other organisms are being reported. However, toxicity information on birds is particularly limited. Birds are primarily exposed to neonicotinoids orally (feeding, preening), by inhalation, or dermally depending on whether the pesticide is applied by aerial spraying or as a seed coating.
The Challenge: Endocrine active chemicals (EAC) are known to interfere with hormonally regulated physiological processes, thereby affecting signaling in the hypothalamic-pituitary-gonadal-liver (HPGL) axis and commonly resulting in reproductive dysfunction. Computational models that relate hormonal and genomic biomarkers within the HPGL axis to the reproductive cycle and ecologically relevant endpoints have been developed for fish; however, no similar model is available for birds. These models are very useful for evaluating how EAC-induced changes in physiological systems enhance or inhibit embryonic development, reproduction, and growth.
The Challenge: Wild birds are exposed throughout their lives to natural and synthetic chemicals that are present in the environment, many of which interfere with the animal’s physiological and developmental systems. Relative concentrations, routes, frequency, and the environment in which chemical exposure occurs will determine to a large extent the bird’s response. Well-designed avian field studies conducted on site are expensive, both in terms of personnel and funding. In order to address specific field exposures and/or focus on variables of particular concern, pen studies can be conducted on a smaller scale. The Japanese quail (Coturnix japonica, JQ) has been used as a model for gallinaceous birds in research because it exhibits a short generation time of 53-74 days and all stages of its development can be maintained and tested in captivity under controlled laboratory pen conditions. As we move towards minimizing the numbers of animals used for research, the role of the JQ as an appropriate model for avian wildlife in ecotoxicological studies is being redefined.
The Challenge: Short-Chain Chlorinated Paraffins (SCCPs) are complex technical mixtures of polychlorinated n-alkanes used in lubricants and coolants in metalworking, as flame retardants, and in paints, adhesives, sealants, textiles and polymeric materials, plastics and rubber. SCCPs are of concern because they are globally transported, bioaccumulate in wildlife and humans, and are environmentally persistent. Their toxicity has been demonstrated in multiple species and their presence has been detected in wild birds and their eggs far from primary manufacturing centers. However, few controlled studies have been conducted to determine the potential hazard and risk that SCCPs pose to free-ranging birds.
The Challenge: The use of flame retardants (FRs) as additives in a variety of consumer use products, including plastics, textiles, and electronics, is projected to continue and increase for the foreseeable future. Because of unanticipated environmental problems, some FRs have either been banned, restricted, or are being phased-out and replaced by other new and presumably safer FRs. Regrettably, many of these alternative FRs are found to bioaccumulate in wildlife tissues, including in bird eggs, suggesting exposure through maternal deposition. However, few data are available on the potential adverse effects in exposed animals.
The Challenge: Neonicotinoids are now the most widely applied class of insecticides in the United States, and are predominantly used in the form of seed treatments. Compared to invertebrates, neonicotinoids are less toxic to wildlife, although genotoxic, cytotoxic, immunological, behavioral and reproductive effects have been reported in studies with birds. At present, little is known about the pharmacokinetics (absorption, distribution, metabolism and excretion) of these pesticides in birds, which can dictate and affect the timecourse of their toxicity. Such information will greatly assist in evaluating the hazard and risk of neonicotinoid seed coatings to wild birds.
The Challenge: Polybrominated diphenyl ether flame retardants (PBDEs) are contaminants that bioaccumulate and biomagnify in aquatic and terrestrial food webs. Unlike many contemporary pollutants, these flame retardants have increased in the environment over the past 30 years. Studies in Chesapeake and Delaware Bays have documented concentrations of nearly 1 μg/g wet weight of PBDEs in osprey eggs, and even greater levels in peregrine falcon eggs. Limited information is available on the toxicity thresholds of these compounds and new organophosphate flame retardants in wildlife.
The Challenge: Emerging contaminants may be in part responsible for recent endocrine disruption observed in fish in the Chesapeake Bay watershed. Endocrine active compounds implicated in the decline of fish populations may affect other wildlife as well. There are 6 species of turtles and 5 of snakes living within the main-stem and tidal areas of the Bay. As poikilotherms, reptiles are dependent on their surrounding habitat for seasonal and daily physiological and behavioral processes. In many cases, their response to changes in their environment is regulated directly or indirectly by their endocrine system. Because embryonic development and reproductive systems are so divergent in the reptilian class, to date in situ EDC research has focused on the oviparous reptile model.
The Challenge: Once common to forest and backyard habitats, the eastern box turtle (Terrapene carolina) has declined sharply. Threats to box turtles include loss and fragmentation of their habitat, road mortality, and commercial taking for the international pet trade. Researchers at the USGS Patuxent Wildlife Research Center have 70 years of records on a turtle population located within a 12 ha forested site along the Patuxent River This long term data set has provided valuable insights into box turtle biology, including information on their home range, seasonal movements, growth and demographic characteristics. However, the density of box turtles at this site seems to have decreased significantly since the mid-1970s, with little indication of recruitment. Given these turtles are located within a wildlife research refuge and protected from habitat loss, vehicular traffic, and commercial harvesting, reasons for their apparent population collapse have yet to be determined.
The survey was conducted in summer 2002 to assess the presence of terrapins in the Maryland portion of the Chesapeake Bay. Results are spatial locations of evidence related to nesting.
Changes in habitat availability for multiple life stages of diamondback terrapins (Malaclemys terrapin) in Chesapeake Bay in response to sea level rise
Global sea level rise (SLR) will significantly alter coastal landscapes through inundation and erosion of lowlying areas. Animals that display area fidelity and rely on fringing coastal habitats during multiple life stages, such as diamondback terrapins (Malaclemys terrapin Schoepff 1793), are likely to be particularly vulnerable to SLR-induced...Woodland, Ryan J.; Rowe, Christopher L.; Henry, Paula F.
Effects on circulating steroid hormones and gene expression along the hypothalamus–pituitary–gonadal axis in adult Japanese quail exposed to 17β-trenbolone across multiple generations
We investigated the effects of the androgenic growth promoter 17β-trenbolone (17βTB) on adult Japanese quail (Coturnix japonica) exposed across three generations. The F0 generation was exposed after sexual maturity to 0, 1, 5, 10, 20, and 40 ppm through feed. The F1 generation was exposed in ovo by maternal transfer and through feed at the same...Karouna-Renier, Natalie K.; Chen, Yu; Henry, Paula F.; Maddox, Catherine M.; Sprague, Dan
Bioaccessibility tests accurately estimate bioavailability of lead to quail
Hazards of soil-borne Pb to wild birds may be more accurately quantified if the bioavailability of that Pb is known. To better understand the bioavailability of Pb to birds, we measured blood Pb concentrations in Japanese quail (Coturnix japonica) fed diets containing Pb-contaminated soils. Relative bioavailabilities were expressed by comparison...Beyer, W. Nelson; Basta, Nicholas T; Chaney, Rufus L.; Henry, Paula F.; Mosby, David; Rattner, Barnett A.; Scheckel, Kirk G.; Sprague, Dan; Weber, John
Evaluating a portable cylindrical bait trap to capture diamondback terrapins in salt marsh
Diamondback terrapins (Malaclemys terrapin) are currently in decline across much of their historical range, and demographic data on a regional scale are needed to identify where their populations are at greatest risk. Because terrapins residing in salt marshes are difficult to capture, we designed a cylindrical bait trap (CBT) that could be...Henry, Paula F.; Haramis, G. Michael; Day, Daniel D.
Spatiotemporal analysis of gene flow in Chesapeake Bay Diamondback Terrapins (Malaclemys terrapin)
There is widespread concern regarding the impacts of anthropogenic activities on connectivity among populations of plants and animals, and understanding how contemporary and historical processes shape metapopulation dynamics is crucial for setting appropriate conservation targets. We used genetic data to identify population clusters and quantify...Converse, Paul E.; Kuchta, Shawn R; Roosenburg, Willem R; Henry, Paula F.; Haramis, G. Michael; King, Timothy L.
Changes in thyroid parameters of hatchling American kestrels (Falco sparverius) following embryonic exposure to technical short chain chlorinated paraffins (SCCPs; C10-13, 55.5% CL)
Chlorinated paraffins (CPs) are complex mixtures of polychlorinated n-alkanes categorized according to their carbon chain length: short chain (SCCPs, C10 – C13), medium (C14 - C17), and long chain (C>17), chlorinated paraffins. SCCPs are primarily used in metalworking applications, as flame retardants, and in paints, adhesives, sealants,...Fernie, Kimberly J; Henry, Paula F.; Letcher, Robert J; Palace, Vince; Peters, Lisa; Rattner, Barnett A.; Sverko, Edward; Karouna-Renier, Natalie K.
Effect of 17β-trenbolone on male and female reproduction in Japanese quail (Coturnix japonica)
The anabolic steroid 17β trenbolone (17β-TB), a known endocrine disrupting chemical, may influence reproductive functions in avian wildlife. We evaluated the effects of dietary exposure to 17β-TB at 5 and 20 ppm on reproductive functional endpoints in Japanese quail during and after sexual maturation. In the male, 5 and 20 ppm...Henry, Paula F.P.; Akuffo, Valorie G.; Chen, Yu; Karouna-Renier, Natalie K.; Sprague, Daniel T.; Bakst, Murray R.
A noninvasive, direct real-time PCR method for sex determination in multiple avian species
Polymerase chain reaction (PCR)-based methods to determine the sex of birds are well established and have seen few modifications since they were first introduced in the 1990s. Although these methods allowed for sex determination in species that were previously difficult to analyse, they were not conducive to high-throughput analysis because of the...Brubaker, Jessica L.; Karouna-Renier, Natalie K.; Chen, Yu; Jenko, Kathryn; Sprague, Daniel T.; Henry, Paula F.P.
Neuroendocrine and behavioral consequences of embryonic exposure to endocrine disrupting chemicalsDawson, Alistair; Sharp, Peter J.; Ottinger, M.A.; Quinn, M.J.; Lavoie, E.; Abdelnabi, M.A.; Thompson, N.; Hazelton, J.; McKernan, M.; Wu, J.; Henry, P.; Viglietti-Panzica, C.; Panzica, G.
Long-term population studies at Patuxent Wildlife Research RefugeSwarth, Chris; Hagood, Susan; Henry, P.
The eastern box turtle at the Patuxent Wildlife Research Center 1940s to the present: another view
Several long-term mark recapture studies have been conducted on box turtles (Terrapene c. carolina) providing valuable information on life span, basic demography, home range, and apparent effects of environmental changes on box turtle survival. One of the longest studied populations was first marked in 1942 on the Patuxent Wildlife Research...Henry, P.F.P.
Impact of vinclozolin on reproductive behavior and endocrinology in Japanese quail (Coturnix coturnix japonica)
The impact of endocrine-disrupting chemicals (EDCs) has been demonstrated in mammalian models, but less research is available for avian species. The effects of vinclozolin (VIN), an antiandrogenic fungicide, on sexual differentiation and maturation were investigated in Japanese quail (Coturnix coturnix japonica). On day 4 of incubation, embryos...McGary, S.; Henry, P.F.P.; Ottinger, M.A.