Connecticut State The Connecticut Agricultural Experiment Station

Scott C. Williams

Headshot photo of Scott Williams, Ph.D. wearing a red hat and a raincoat.

Department of Environmental Science and Forestry
The Connecticut Agricultural Experiment Station
123 Huntington Street
New Haven, CT 06511
Voice: (203) 974-8609 Fax: (203) 974-8502
E-mail: Scott.Williams@ct.gov

Expertise:

Scott’s field of expertise is wildlife generally, but more specifically in terms of their role in the tick and tick-borne disease system. Using our knowledge of both tick and wildlife ecology, we can exploit weakness in their life cycles to manage ticks effectively with minimal harm to beneficial insects and our environment. Scott also researches overabundant white-tailed deer herds and their impact on native and managed ecosystems, orchards, gardens, and landscape plantings. He is also knowledgeable about Connecticut flora and fauna including songbirds and other migratory birds, game birds, small- and medium-sized mammals, and fish.

 

Education:
Ph. D.--The University of Connecticut (Natural Resources) 2008
M. E. S.--Yale University School of Forestry and Environmental Studies (Environmental Studies) 2000
B. A.--Connecticut College (Environmental Studies) 1997
CWB--Certified Wildlife Biologist®, The Wildlife Society 2010

 

Station Career:

Chief Scientist/Department Head, 2022-present

Agricultural Scientist, 2019-2022
Associate Agricultural Scientist, 2014-2019
Assistant Agricultural Scientist II, 2008-2014
Research Technician I, 2003-2008
Research Assistant III, 2001-2003
Research Assistant II, 2000-2001

 

Non-Station Career:

Adjunct Professor, Department of Biology and Environmental Science, University of New Haven, West Haven, CT, August 2013-present.

Adjunct Professor, Department of Natural Resources and the Environment, University of Connecticut, Storrs, CT September 2011-present

Past Research:

Ph. D. research included the use of global positioning system devices to monitor differences in behavior, habitat usage, and home range plasticity of deer subjected to different methods of lethal removal on a private estate in New Jersey. Earlier Station research included assisting with the development of a novel, non-lethal sterilization procedure for male white-tailed deer (Odocoileus virginianus). Also evaluation of white-tailed deer as seed dispersal agents, cost assessment and accuracy of different methods of deer population estimation, deer damage abatement, impacts of deer herbivory on forested ecosystems, and deer capture work for range assessment, usage of suburban environments, dispersal rates, tick and mosquito borne disease monitoring, and genetic analysis of animals within the herd. The use of repellents in deterring damage from the impacts of deer and eastern cottontail (Sylvilagus floridanus) herbivory were also evaluated. Also, collaborative research involving Japanese barberry (Berberis thunbergii) control strategies led to the eventual discovery of a positive relationship between barberry infestations, blacklegged or “deer” ticks (Ixodes scapularis), and the Lyme disease-causing spirochete (Borrelia burgdorferi). It was found that the growth form of barberry retains humidity throughout the day providing an ideal microclimate for tick survival and reproduction and managing barberry creates a less humid/more hostile environment for ticks.

 

Current Research:

Current Station research includes the role of overabundant deer in shaping native ecosystems, specifically the connection between forest and public health. Additionally, research efforts include collaborative integrated tick management investigations of the most effective and least toxic combinations of treatments to successfully reduce blacklegged tick abundances and associated disease risk in residential areas. Specifically, we are investigating the oral delivery of systemic acaricide treatment of tick hosts such as white-footed mice (Peromyscus leucopus) and white-tailed deer (just like treating your pets for ticks and fleas) and how that can have a positive impact on reduction in areawide tick abundances. We are also experimenting with differing seasonal spray strategies to be effective in managing tick abundances with synthetic acaricides while limiting negative impacts to the environment and beneficial insects such as butterflies and other pollinator species.

 

Selected publications available from the author, Scott.Williams@ct.gov

 

Integrated Tick and Pathogen Management 

  • Brown, J. E., Linske, M. A., DeNicola, A. J., DeNicola, V. L., Boulanger, J. R., Tamez, C., and Williams, S. C. (2026). Oral delivery of the systemic acaricide moxidectin to a confined Odocoileus virginianus herd parasitized by Ixodes scapularis. Journal of Medical Entomology 63(1):tjag022. https://doi.org/10.1093/jme/tjag022

  • Carrascal, D. R., Bastard, J., Williams, S. C., and Diuk-Wasser, M. (2024). Modeling platform to assess the effectiveness of single and integrated Ixodes scapularis tick control methods. Parasites & Vectors: 17(339). https://doi.org/10.1186/s13071-024-06387-2

  • Williams, S. C. and Linske, M. A. (2024). Late fall synthetic acaricide application is effective at reducing host-seeking adult and nymphal Ixodes scapularis (Ixodida: Ixodidae) abundances the following spring. Journal of Medical Entomology, tjae044. DOI: 10.1093/jme/tjae044
  • Linske, M. A., and Williams, S. C. (2024). Evaluation of landscaping and vegetation management to suppress host-seeking Ixodes scapularis (Ixodida: Ixodidae) nymphs on residential properties in Connecticut, USA. Environmental Entomology, nvae007. DOI: 10.1093/ee/nvae007
  • Earnest, R., Hahn, A. M., Feriancek, N. M., Brandt, M., Filler, R. B., Zhao, Z., Breban, M. I., Vogels, C. B., Chen, N. F., Koch, R. T., Porzucek, A. J., Sodeinde, A., Garbiel, A., Keanna, C., Litwak, H., Stuber, H. R., Cantoni, J. L., Pitzer, V. E., Olarte Castillo, X. A., Goodman, L. B., Wilen, C. B., Linske, M. A., Williams, S. C., and Grubaugh, N. D. (2023). Survey of white-footed mice in Connecticut, USA reveals low SARS-CoV-2 seroprevalence and infection with divergent betacoronaviruses. npj Viruses, 1(10). DOI: 10.1038/s44298-023-00010-4
  • Holcomb, K., Khalil, N., Cozens, D. W., Cantoni, J. L., Brackney, D. E., Linske, M. A., Williams, S. C., Molaei, G., and Eisen, R. J. (2023). Comparison of acarological risk metrics derived from active and passive surveillance and their concordance with tick-borne disease incidence. Ticks and Tick-borne Diseases, 14: 102243. DOI: 10.1016/j.ttbdis.2023.102243
  • Stafford, K. C. III, Molaei, G., Williams, S. C., and Mertins, J. W. (2023). Introduction of the ectoparasite and vector of human and veterinary disease pathogens Rhipicephalus pulchellus (Acari: Ixodidae) into Connecticut with a traveler from Tanzania. Journal of Medical Entomology, tjad109. DOI: 10.1093/jme/tjad109
  • Williams, S. C., Linske, M. A., and Stafford, K. C. III. (2023). Orally delivered fipronil-laced bait reduces juvenile blacklegged tick (Ixodes scapularis) burdens on wild white-footed mice (Peromyscus leucopus). Ticks and Tick-borne Diseases, 14: 102189. DOI: 10.1016/j.ttbdis.2023.102189
  • Williams, S. C., Linske, M. A., DeNicola, A. J., DeNicola, V. L., and Boulanger, J. R. (2023). Experimental oral delivery of the systemic acaricide moxidectin to free-ranging white-tailed deer (Artiodactyla: Cervidae) parasitized by Amblyomma americanum (Ixodida: Ixodidae). Journal of Medical Entomology, 60: tjad056. DOI: 10.1093/jme/tjad056
  • Vogels, C. B. F., Dupuis, A. P. II, Robich, R. M., Fauver, J. R., Brito, A. F., Williams, S. C., Anderson, J. F., Lubelczyk, C. B., Lange, R. E., Prusinski, M. A., Kramer, L. D., Gangloff-Kaufmann, J. L., Goodman, L. B., Baele, G., Smith, R. P., Armstrong, P. M., Ciota, A. T., Dellicour, S., and Grubaugh, N. D. (2023). Phylogeographic reconstruction of the emergence and spread of Powassan virus in the northeastern United States. Proceedings of the National Academy of Sciences, 120, e2218012120. DOI: 10.1073/pnas.2218012120
  • Chand, M., Choi, J. Y., Pal, A. C., Singh, P., Kumari, V., Thekkiniath, J., Gagnon, J., Timalsina, S., Gaur, G., Williams, S. C., Ledizet, M., Ben Mamoun, C. 2022. Epitope profiling of monoclonal antibodies to the immunodominant antigen BmGPI12 of the human pathogen Babesia microti. Frontiers in Cellular and Infection Microbiology, 12, 1754. DOI: 10.3389/fcimb.2022.1039197
  • Stafford, K. C. III, Molaei, G., Williams, S. C., and Mertins, J. W. (2022). Introduction of the geographically restricted South African tick species Rhipicephalus capensis (Acari: Ixodidae) into the United States with a human traveler. Ticks and Tick-Borne Diseases, 13. DOI: 10.1016/j.ttbdis.2022.101912
  • Linske, M. A., Williams, S. C., Stafford, K. C. III, and Li, A. (2021). Integrated tick management in Guilford, CT: Fipronil-based rodent-targeted bait box deployment configuration and Peromyscus leucopus (Rodentia: Cricetidae) abundance drive reduction in tick burdens. Journal of Medical Entomology, 59, 591-597. DOI: 10.1093/jme/tjab200
  • Molaei, G., Little, E. A. H., Williams, S. C., and Stafford, K. C. III. (2021). First record of established populations of the invasive pathogen vector and ectoparasite Haemaphysalis longicornis (Acari: Ixodidae) in Connecticut, USA. Journal of Medical Entomology, 58, 2508-2513. DOI: 10.1093/jme/tjab117
  • Williams, S. C., Stafford, K. C. III, Linske, M. A., Brackney, D. E., LaBonte, A. M., Stuber, H. R., and Cozens, D. W. (2021). Effective control of the motile stages of Amblyomma americanum and reduced Ehrlichia spp. prevalence in adults via permethrin treatment of white-tailed deer in coastal Connecticut, USA. Ticks and Tick-Borne Diseases, 12. DOI: 10.1016/j.ttbdis.2021.101675
  • Linske, M. A., Williams, S. C., Stafford, K. C. III, Lubelczyk, C. B., Henderson, E. F., Welch, M., and Teel, P. D. (2020). Determining effects of winter weather conditions on adult Amblyomma americanum (Acari: Ixodidae) survival in Connecticut and Maine, USA. Insects, 11(1), 13. DOI: 10.3390/insects11010013
  • Machtinger, E. T. and Williams, S. C. (2020). Practical guide to trapping Peromyscus leucopus and Peromyscus maniculatus for vector and vector-borne pathogen surveillance and ecology. Journal of Insect Science, 20, 1-19. DOI: 10.1093/jisesa/ieaa028
  • Stafford, K. C. III, Williams, S. C., van Oosterwijk, J. G., Linske, M. A., Zatechka, S., Richer, L. M., Molaei, G., Przybyszewski, C., and Wikel, S. K. (2020). Field evaluation of a novel oral reservoir-targeted vaccine against Borrelia burgdorferi utilizing an inactivated whole-cell bacterial antigen expression vehicle. Experimental and Applied Acarology, 80, 257-268. DOI: 10.1007/s10493-019-00458-1
  • Williams, S. C., Linske, M. A., and Stafford, K. C. III. (2020). Humane use of cardiac puncture for non-terminal phlebotomy of wild-caught and released Peromyscus spp. Animals, 10(5), 826. DOI: 10.3390/ani10050826
  • Williams, S. C., van Oosterwijk, J. G., Linske, M. A., Zatechka, S., Richer, L. M., Przybyszewski, C., Wikel, S. K., and Stafford, K. C. III. (2020). Administration of an orally delivered substrate targeting a mammalian zoonotic pathogen reservoir population: Novel application and biomarker analysis. Vector-Borne and Zoonotic Diseases, 20, 603-612. DOI: 10.1089/vbz.2019.2612
  • Little, E. A. H., Williams, S. C., Stafford, K. C. III, Linske, M. A., and Molaei, G. (2019). Evaluating the effectiveness of an integrated tick management approach on multiple pathogen infection in Ixodes scapularis questing nymphs and larvae parasitizing white-footed mice. Experimental and Applied Acarology, 80, 127-136. DOI: 10.1007/s10493-019-00452-7
  • Williams, S. C., Little, E. A. H., Stafford, K. C. III, Molaei, G., and Linske, M. A. (2018). Integrated control of juvenile Ixodes scapularis parasitizing Peromyscus leucopus in residential southwestern Connecticut. Ticks and Tick-Borne Diseases, 9, 1310-1316. DOI: 10.1016/j.ttbdis.2018.05.014
  • Williams, S. C., K. C. Stafford, III, Molaei, G., and Linske, M. A. (2018). Integrated control of nymphal Ixodes scapularis: Effectiveness of white-tailed deer reduction, the entomopathogenic fungus Metarhizium anisopliae, and fipronil-based rodent bait boxes. Vector-Borne and Zoonotic Diseases, 18, 55-64. DOI: 10.1089/vbz.2017.2146
  • Stafford, K. C. III and Williams, S. C. (2017). Deer-targeted methods: A review of the use of topical acaricides for the control of ticks on white-tailed deer. Journal of Integrated Pest Management, 8. DOI: 10.1093/jipm/pmx014
  • Stafford, K. C. III, Williams, S. C., and Molaei, G. (2017). Integrated pest management in controlling ticks and tick-associated diseases. Journal of Integrated Pest Management, 8(1). DOI: 10.1093/jipm/pmx018

 

Tick Overwintering Survival and Range Expansion

  • Price, L. E., Winter, J. M., Cantoni, J. L., Cozens, D. W., Linske, M. A., Williams, S. C., Dill, G. M., Gardner, A. M., Elias, S. P., Rounsville, Jr., T. F., Smith, Jr., R. P., Palace, M. W., Herrick, C., Prusinski, M. A., Casey, P., Doncaster, E. M., Savage, J. D. T., Wallace, D. I., and Shi., X. (2024). Spatial and temporal distribution of Ixodes scapularis and tick-borne pathogens across the northeastern United States. Parasites & Vectors: 17(481). https://doi.org/10.1186/s13071-024-06518-9

  • Linske, M. A., Williams, S. C., Stafford, K. C. III, Lubelczyk, C. B., Henderson, E. F., Welch, M., and Teel, P. D. (2020). Determining effects of winter weather conditions on adult Amblyomma americanum (Acari: Ixodidae) survival in Connecticut and Maine, USA. Insects, 11(1), 13. https://doi.org/10.3390/insects11010013
  • Linske, M. A., Stafford, K. C. III, Williams, S. C., Lubelczyk, C. B., Welch, M., and Henderson, E. F. (2019). Impacts of deciduous leaf litter and snow presence on nymphal Ixodes scapularis (Acari: Ixodidae) overwintering survival in coastal New England, USA. Insects, 10(8), 227. https://doi.org/10.3390/insects10080227
  • Molaei, G. M., Little, E. A. H., Williams, S. C., and Stafford, K. C. III. (2019). Bracing for the worst: Will range expansion of the lone star tick, Amblyomma americanum, alter the tick-borne disease landscape in the northeastern United States? New England Journal of Medicine, 381, 2189-2192. https://doi.org/10.1056/NEJMp1911661

Tick-Borne Pathogen and Disease Screening and Ecology

  • Ibemgbo, S., Compton, S., Breban, M. I., Redmond, S., Grubaugh, N. D., Linske, M., Williams, S., Zyskowski, K., Watkins-Colwell, G., Lewis, J., Syracuse, M., Risatti, G., Tanner, W. D., and Zeiss, C. (2025). The coronaviral landscape across diverse mammalian species in the northeastern United States. Scientific Reports: 16(2942). https://doi.org/10.1038/s41598-025-32849-3

  • Linske, M. A., Williams, S. C., Stafford, K. C. III, and Ortega, I. M. (2018). Ixodes scapularis reservoir host diversity and abundance impacts on dilution of Borrelia burgdorferi in residential and woodland habitats in Connecticut, USA. Journal of Medical Entomology, 55, 681-690. https://doi.org/10.1093/jme/tjx237.
  • Thekkiniath J., Mootien, S., Lawres, L., Perrin, B., Gewirtz, M., Krause, P., Williams, S. C., Doggett, J., Ledizet, M., and Ben Mamoun, C. (2018). BmGPAC: an antigen capture assay for detection of active Babesia microti infection. Journal of Clinical Microbiology, 56(10). https://doi.org/10.1128/JCM.00067-18.
  • Cornillot, E., Dassouli, A., Pachikara, N., Lawres, L., Renard, I., Francois, C., Randazzo, S., Brès, V., Garg, A., Brancato, J., Pazzi, J. E., Pablo, J., Hung, C., Teng, A., Shandling, A. D., Huynh, V. T., Krause, P. J., Lepore, T., Delbecq, S., Hermanson, G., Liang, X., Williams, S. C., Molina, D. M., and Ben Mamoun, C. (2016). A targeted immunomic approach identifies diagnostic antigens in the human pathogen Babesia microti. Transfusion, 56, 2085-2099. https://doi.org/10.1111/trf.13640.
  • Stafford, K. C., III, Williams, S. C., Magnarelli, L. A., Bharadwaj, A., Eretl, S. H., and Nelson, R. S. (2014). Expansion of zoonotic babesiosis and reported human cases, Connecticut, 2001-2010. Journal of Medical Entomology, 51, 245-252. https://doi.org/10.1603/ME13154.
  • Magnarelli, L. A., Williams, S. C., Norris, S. J., and Fikrig, E. (2014). Serum antibodies to Borrelia burgdorferi, Anaplasma phagocytophilum, and Babesia microti in recaptured white-footed mice. Journal of Wildlife Diseases, 49, 294-302. https://doi.org/10.7589/2012-06-172.
  • Magnarelli, L. A., Williams, S. C., and Fikrig, E. (2010). Seasonal prevalence of serum antibodies to whole cell and recombinant antigens of Borrelia burgdorferi and Anaplasma phagocytophilum in white-tailed deer in Connecticut. Journal of Wildlife Diseases, 46, 781-790. https://doi.org/10.7589/0090-3558-46.3.781.

White-tailed Deer Ecology and Management

  • Ward, J. S. and Williams, S. C. (2020). Influence of deer hunting and residual stand structure on tree regeneration in deciduous forests. Wildlife Society Bulletin, 44, 519-530. https://doi.org/10.1002/wsb.1120
  • Williams, S. C. and Gregonis, M. A. (2015). Survival and movement of rehabilitated white-tailed deer fawns in Connecticut. Wildlife Society Bulletin, 39, 664-669. https://doi.org/10.1002/wsb.562.
  • Yan, J., Chen, Y., Lawrence-Apfel, K., Ortega, I., Pozdnyakov, V., Williams, S. C., and Meyer, T. (2014). A moving-resting process with an embedded Brownian motion for animal movements. Population Ecology, 56, 401-415. https://doi.org/10.1007/s10144-013-0428-8.
  • Williams, S. C., DeNicola, A. J., Almendinger, T., and Maddock, J. (2014). Evaluation of traditional hunting as an overabundant deer management technique in suburban landscapes. Wildlife Society Bulletin, 37, 137-145. https://doi.org/10.1002/wsb.236.
  • DeNicola, A. J. and Williams, S. C. (2008). Sharpshooting suburban white-tailed deer reduces deer-vehicle collisions. Human-Wildlife Conflicts, 2, 28-33. https://digitalcommons.unl.edu/cgi/viewcontent.cgi?article=1068&context=hwi.
  • Williams, S. C., DeNicola, A. J., and Ortega, I. M. (2008). Behavioral responses of white-tailed deer subjected to lethal management. Canadian Journal of Zoology, 86, 1358-1366. https://doi.org/10.1139/Z08-126.
  • Williams, S. C., Ward, J. S., and Ramakrishnan, U. (2008). Endozoochory by white-tailed deer (Odocoileus virginianus) across a suburban/woodland interface. Forest Ecology and Management, 255, 940-947. https://doi.org/10.1016/j.foreco.2007.10.003.
  • Williams, S. C. and Ward, J. S. (2006). Exotic seed dispersal by white-tailed deer in southern Connecticut. Natural Areas Journal, 26, 383-390. https://doi.org/10.3375/0885-8608(2006)26[383:ESDBWD]2.0.CO;2.
  • Williams, S. C. and DeNicola, A. J. (2002). Home range increase of lactating female white-tailed deer following herd reduction. Northeast Wildlife, 57: 29-38.
  • Williams, S. C. and DeNicola, A. J. (2000). Spatial movements in response to baiting female white-tailed deer. In: M. C. Brittingham, J. Kays, and R. McPeake, editors. Proceedings of the 9th Annual Wildlife Damage Management Conference. Penn State University, State College, PA. Pages 206-224. https://portal.ct.gov/-/media/CAES/DOCUMENTS/Biographies/Williams/WilliamsandDeNicola2000pdf.pdf?la=en.

Herbivory by White-tailed Deer and Eastern Cottontails

Forest and Invasive Species Management and Ecology

  • Ward, J. S. and Williams, S. C. (2018). Effect of tree diameter, canopy position, age, and browsing on stump sprouting in southern New England. Forest Science, 64, 452-460. https://doi.org/10.1093/forsci/fxx023.
  • Ward, J. S., Williams, S. C., and Linske, M. A. (2017). Influence of invasive shrubs and deer browsing on regeneration in temperate deciduous forests. Canadian Journal of Forest Research, 48(1): 58-67. https://doi.org/10.1139/cjfr-2017-0208.
  • Ward, J. S., Williams, S. C., and Worthley, T. E. (2014). Comparing effectiveness and impacts of Japanese barberry (Berberis thunbergii) control treatments and herbivory on plant communities. Invasive Plant Science and Management, 6, 459-469. https://doi.org/10.1614/IPSM-D-13-00004.1.
  • Ward, J. S. and Williams, S. C. (2011). Controlling an invasive shrub, Japanese barberry (Berberis thunbergii DC), using directed heating with propane torches. Natural Areas Journal, 31, 500-506. https://doi.org/10.3375/043.031.0208.
  • Ward, J. S., Williams, S. C., and Worthley, T. E. (2010). Effectiveness of two-stage control strategies for Japanese barberry (Berberis thunbergii) varies by initial clump size. Invasive Plant Science and Management, 3, 60-69. https://doi.org/10.1614/IPSM-D-09-00003.1.
  • Ward, J. S., Worthley, T. E., and Williams, S. C. (2009). Controlling Japanese barberry (Berberis thunbergii DC) in southern New England. Forest Ecology and Management, 257, 561-566. https://doi.org/10.1016/j.foreco.2008.09.032.

 

Tick, Deer, and Invasive Plant Interactions

  • Linske, M. A., Williams, S. C., Ward, J. S., and Stafford, K. C. III. (2018). Indirect effects of Berberis thunbergii infestations on Peromyscus leucopus exposure to Borrelia burgdorferi. Environmental Entomology, 47, 795-802. https://doi.org/10.1093/ee/nvy079.
  • Ward, J. S., Williams, S. C., and Linske, M. A. (2017). Independent effects of invasive shrubs and deer herbivory on plant community dynamics. Forests, 8(2), 1-18. https://doi.org/10.3390/f8010002.
  • Williams, S. C., Linske, M. A., and Ward, J. S. (2017). Long-term effects of Berberis thunbergii management on Ixodes scapularis abundance and Borrelia burgdorferi prevalence in Connecticut, USA. Environmental Entomology, 46, 1329-1338. https://doi.org/10.1093/ee/nvx146.
  • Williams, S. C. and Ward, J. S. (2010). Effects of Japanese barberry (Ranunculales: Berberidaceae) removal and resulting microclimatic changes on Ixodes scapularis (Acari: Ixodidae) abundances in Connecticut, USA. Environmental Entomology, 39, 1911-1921. https://doi.org/10.1603/EN10131.
  • Williams, S. C., Ward, J. S., Worthley, T. E., and Stafford, K. C. III. (2009). Managing Japanese barberry (Ranunculales: Berberidaceae) infestations reduces blacklegged tick (Acari: Ixodidae) abundance and infection prevalence with Borrelia burgdorferi (Spirochaetales: Spirochaetaceae.) Environmental Entomology, 38, 977-984. https://doi.org/10.1603/022.038.0404