Sasha Tetzlaff, PhD Wildlife ecology, management, and conservation

About me

I'm a Research Biologist for the US Army Corps of Engineers ERDC-CERL, Adjunct Faculty in Wildlife Ecology and Conservation (Distance Education) at Unity Environmental University, and Research Institute Affiliate with the Illinois Natural History Survey. I hold a PhD in Natural Resources and Environmental Sciences from University of Illinois, MS in Biological Sciences from Purdue University, and BA in Environmental Studies from Florida Gulf Coast University. Aside from working in government and academic roles, I have also been an educator and animal caretaker at multiple zoos.

Sasha.J.Tetzlaff@usace.army.mil

Research

My research interests are broad and encompass various aspects of wildlife ecology—particularly for threatened, endangered, and at-risk species. An overarching goal of my work is to integrate multiple disciplines to inform wildlife management and conservation issues. This has led to field and laboratory studies focused on:

  • movement and space use
  • habitat selection
  • physiology
  • foraging
  • wildlife diseases
  • captive animal welfare
  • reintroduction biology
  • animal personality
  • predator-prey interactions
  • social network analysis
  • modeling population and community parameters (e.g., occupancy, abundance, and survival) using numerous survey techniques (e.g., eDNA, acoustic monitoring, visual encounter).

Select Current Research Projects

Predictors of species occupancy using eDNA metabarcoding: DNA metabarcoding of environmental samples (e.g., air, water, soil) has emerged as a cost-effective and reliable means for rapidly assessing ecological communities across large areas. In collaboration with Dr. Aron Katz, Dr. Mark Johnson, Dr. Jinelle Sperry, and US Army land managers, we are examining predictors of eDNA occupancy for numerous species. Example projects include investigating ecological correlates of occurrence for native fish, introduced fish competitors, and fish parasites; and whether eDNA occupancy for freshwater mussels can be reliably predicted by habitat quality metrics and presence of fish hosts.

Multi-method assessments for characterizing animal communities: Species detections during formal surveys can differ depending on the survey methods employed. In collaboration with Dr. Aron Katz, Patrick Wolff, and US Army biologists, we are exploring how species detections differ based on survey methodologies, such as how vertebrate taxonomic detections from eDNA surveys compare to camera traps.

Timber rattlesnake population ecology: Long-term data are often necessary for adequately understanding population dynamics of long-lived species. In collaboration with Dr. Bill Brown, Dr. Eric Hileman, Dr. Mark Davis, Dr. Gordon Schuett, and Matt Simon, we are investigating the demography of a timber rattlesnake population in New York that Dr. Brown began studying over four decades ago.

Demographic trends for game animals on military lands: In collaboration with Dr. Jinelle Sperry, Patrick Wolff, and US Army biologists, we are using long-term (>20 year) datasets to investigate trends for populations of white-tailed deer (Odocoileus virginianus) and wild pigs (Sus scrofa) on US Army installations.

Vulnerability of imperiled species to climate change: In collaboration with Dr. Jinelle Sperry and numerous US Army scientists, we are developing an interactive tool for assessing threatened, endangered, and at-risk species' vulnerability to climate change on Department of Defense installations.

Publications

2023

35. Katz, A.D., S.J. Tetzlaff, M.D. Johnson, and J.H. Sperry. 2023. Molecular identification and environmental DNA detection of gill lice ectoparasites associated with Brook Trout declines. Transactions of the American Fisheries Society 152: 788–808.

34. Tetzlaff, S.J., J. Vizentin-Bugoni, J.H. Sperry, M.A. Davis, R.W. Clark, R. Repp, and G.W. Schuett. 2023. Fission-fusion dynamics in the social networks of a North American pitviper. Ecology and Evolution 13: e10339.

33. Tetzlaff, S.J., M.A. Davis, G.W. Schuett, E.T. Hileman, J.H. Sperry, and W.S. Brown. 2023. Maladapted in the Anthropocene: communal hyperfidelity in snakes. Frontiers in Ecology and the Environment 21: 266–268.

32. Johnson, M.J., A.D. Katz, M.A. Davis, S.J. Tetzlaff, D. Edlund, S. Tomczyk, B. Molano-Flores, T. Wilder, and J.H. Sperry. Environmental DNA metabarcoding from flowers reveals arthropod pollinators, plant pests, parasites, and potential predator-prey interactions while revealing more arthropod diversity than camera traps. Environmental DNA 5: 551–569.

2022

31. Tetzlaff, S.J., A.D. Katz, J.H. Sperry, E.C. Sternhagen, P.J. Wolff, B.W. Huggett, M.A. Davis. 2022. Hemidactylium scutatum (Four-Toed Salamander) Geographic Distribution. Herpetological Review 53: 68.

30. Tetzlaff, S.J., J.H. Sperry, and B.A. DeGregorio. 2022. You can go your own way: No evidence for social behavior based on kinship or familiarity in captive juvenile box turtles. Applied Animal Behaviour Science 248: 105586.

2020

29. Tetzlaff, S.J., C.J. Robinson, B.A. Kingsbury, J.H. Sperry, and B.A. DeGregorio. 2020. Predators may lose interest in turtle acclimation pens: implications for translocations using soft release. Chelonian Conservation and Biology 19: 141–144.

28. Carlson, B.E. and S.J. Tetzlaff. 2020. Long-term behavioral repeatability in wild adult and captive juvenile turtles (Terrapene carolina): implications for personality development. Ethology 126: 668–678 (cover photo).

27. Tetzlaff, S.J., D.C. Messmann, J.H. Sperry, and B.A. DeGregorio. 2020. An inexpensive box trap with potential to improve welfare of captured herpetofauna. Herpetology Notes 13: 151–155.

26. Tetzlaff, S.J., A. Estrada, B.A. DeGregorio, and J.H. Sperry. 2020. Identification of factors affecting predation risk for juvenile turtles using 3D printed models. Animals 10: 275 (article in the Special Issue Demonstration of Innovative Approaches for Advancing Wildlife Research).

2019

25. Tetzlaff, S.J. and K.D. Tetzlaff. 2019. Lithobates catesbeianus (American Bullfrog) Predation. Herpetological Review 50: 547.

24. Tetzlaff, S.J., J.H. Sperry, B.A. Kingsbury, and B.A. DeGregorio. 2019. Captive-rearing duration may be more important than environmental enrichment for enhancing turtle head-starting success. Global Ecology and Conservation 20: e00797 (featured by The Wildlife Society).

23. Tetzlaff, S.J., J.H. Sperry, and B.A. DeGregorio. 2019. Effects of antipredator training, environmental enrichment, and soft release on wildlife translocations: a review and meta-analysis. Biological Conservation 236: 324–331.

22. Tetzlaff, S.J., J.H. Sperry, and B.A. DeGregorio. 2019. Tradeoffs with growth and behavior for captive box turtles head-started with environmental enrichment. Diversity 11: 40 (article in the Special Issue Advances in the Biology and Conservation of Turtles).

2018

21. Tetzlaff, S.J., J.H. Sperry, and B.A. DeGregorio. 2018. Attempted depredation of a juvenile Eastern Box Turtle, Terrapene carolina (Linnaeus, 1758), by Sandhill Cranes, Antigone canadensis (Linnaeus, 1758). Herpetology Notes 11: 589–591.

20. Tetzlaff, S.J., J.H. Sperry, and B.A. DeGregorio. 2018. Captive-reared juvenile box turtles innately prefer naturalistic habitat: implications for translocation. Applied Animal Behaviour Science 204: 128–133.

19. DeGregorio, B.A., M.J. Ravesi, J.H. Sperry, S.J. Tetzlaff, J.M. Josimovich, M. Matthews, and B.A. Kingsbury. 2018. Daily and seasonal activity patterns of the Massasauga (Sistrurus catenatus): an automated radio telemetry study. Herpetological Conservation and Biology 13: 10–16.

18. Hileman, E.T., M.C. Allender, D.R. Bradke, L.J. Faust, J.A. Moore, M.J. Ravesi, and S.J. Tetzlaff. 2018. Estimation of Ophidiomyces prevalence to evaluate snake fungal disease risk. The Journal of Wildlife Management 82: 173–181 (featured by Undark).

2017

17. Tetzlaff, S.J., M.J. Ravesi, M.C. Allender, E.T. Carter, B.A. DeGregorio, J.M. Josimovich, and B.A. Kingsbury. 2017. Snake fungal disease affects behavior of free-ranging Massasauga Rattlesnakes (Sistrurus catenatus). Herpetological Conservation and Biology 12: 624–634.

16. Tetzlaff, S.J., E.T. Carter, B.A. DeGregorio, M.J. Ravesi, and B.A. Kingsbury. 2017. To forage, mate, or thermoregulate: influence of resource manipulation on male rattlesnake behavior. Ecology and Evolution 7: 6606–6613.

2016

15. Ravesi M.J., S.J. Tetzlaff, M.C. Allender, and B.A. Kingsbury. 2016. Detection of Snake Fungal Disease from a Lampropeltis triangulum (Eastern Milksnake) in northern Michigan. Northeastern Naturalist 23: N18–N21.

14. Tetzlaff, S.J. and N.G. Schiltz. 2016. Terrapene carolina (Eastern Box Turtle) Scavenging. Herpetological Review 47: 453–454.

13. Allender, M.C., E.T. Hileman, J.A. Moore, and S.J. Tetzlaff. 2016. Detection of Ophidiomyces, the causative agent of snake fungal disease, in the Eastern Massasauga (Sistrurus catenatus) in Michigan. Journal of Wildlife Diseases 52: 694–698.

12. Tetzlaff, S.J., K.E. Tetzlaff, and R.J. Connors. 2016. Evaluation of thermal regimes for transported ambassador ectotherms: one size does not fit all. Zoo Biology 35: 339–345.

11. Tetzlaff, S.J., M.J. Ravesi, and B.A. Kingsbury. 2016. Sistrurus catenatus (Massasauga) Activity Range Lengths. Herpetological Review 47: 154–155.

10. Ravesi, M.J., S.J. Tetzlaff, and B.A. Kingsbury. 2016. Sistrurus catenatus (Massasauga) Diet. Herpetological Review 47: 153–154.

2015

9. Ravesi, M.J., M.J. Forzley, S.J. Tetzlaff, B.A. Kingsbury, and J.M. Parker. 2015. Sistrurus catenatus (Massasauga) Diet. Herpetological Review 46: 453–454.

8. Ravesi, M.J., S.J. Tetzlaff, and B.A. Kingsbury. 2015. Sistrurus catenatus (Massasauga) Overwintering Site. Herpetological Review 46: 454.

7. Tetzlaff, S.J. and M.J. Ravesi. 2015. Glyptemys insculpta (Wood Turtle) Mortality. Herpetological Review 46: 243.

6. Tetzlaff, S.J., M.J. Ravesi, J.M. Parker, M.J. Forzley, and B.A. Kingsbury. 2015. Feeding and breeding: a northern population of Massasauga Rattlesnakes, Sistrurus catenatus (Rafinesque 1818), continues to hunt during the mating season. Herpetology Notes 8: 277–280.

5. Tetzlaff, S.J., M.C. Allender, M.J. Ravesi, J.A. Smith, and B.A. Kingsbury. 2015. First report of snake fungal disease from Michigan, USA involving Massasaugas, Sistrurus catenatus (Rafinesque 1818). Herpetology Notes 8: 31–33.

2014

4. Tetzlaff, S.J., M.J. Ravesi, and B.A. Kingsbury. 2014. Sistrurus catenatus catenatus (Eastern Massasauga) Diet. Herpetological Review 45: 712–713.

3. Tetzlaff, S.J. 2014. Diadophis punctatus (Ring-necked Snake) Diet. Herpetological Review 45: 710.

2. Tetzlaff, S.J. 2014. Crotalus horridus (Timber Rattlesnake) Habitat Use. Herpetological Review 45: 709.

1. Tetzlaff, S.J., D.L. Tetzlaff, M. Schoenbeck, and N. Clark. 2014. Agkistrodon piscivorus conanti (Florida Cottonmouth) Diet and Phenotype. Herpetological Review 45: 511–512.

Teaching

My development as an educator began when I was employed by multiple zoological parks, where I spent several years teaching the public about the natural world. In these positions, the importance of effective messaging and the positive impact educators can have was instilled. Having transitioned to more "traditional" instruction in academia, I thoroughly enjoy teaching and mentoring diverse students and helping them achieve their educational and career goals.

Courses Taught

Unity Environmental University: MATH 620 Statistics and Data Management for Science Professionals (I developed this course), MATH 401 Statistics for Wildlife Professionals, WCON 303 Life History and Identification of Birds and Mammals, BIOL 105 and 106 Biological Diversity, Ecology, and Evolution with labEVPC 101 Professional Skills

College of DuPage: BIOLO 1151 Principles of Biological Science with lab

University of St. Francis: BIOL 125 Principles of Biology I lab

Purdue University Fort Wayne: BIOL 109 Biology of Animals lab, BIOL 117 Principles of Ecology and Evolution lab, BIOL 203 Human Anatomy and Physiology lab, BIOL 108 Biology of Plants lab

Terra State Community College: CIT 1090 Computer Fundamentals

Past and Present Collaborators

I am very fortunate to work or have worked with such great people.

Jinelle Sperry, US Army ERDC-CERL and University of Illinois Urbana-Champaign

Brett DeGregorio, USGS and Michigan State University

Michael Ravesi, State of Connecticut Department of Energy and Environmental Protection

Pat Wolff, US Army ERDC-CERL

Aron Katz, US Army ERDC-CERL

Mark Johnson, US Army ERDC-CERL

Mark Davis, Illinois Natural History Survey

Gordon Schuett, Chiricahua Desert Museum and University of Georgia

Eric Hileman, Mississippi State University

William Brown, Skidmore College (emeritus)

Evin Carter, Oak Ridge National Laboratory

Bradley Carlson, Wabash College

Jef Vizentin-Bugoni, Universidade Federal de Pelotas

Rulon Clark, San Diego State University

Bruce Kingsbury, Purdue University Fort Wayne

Matthew Allender, University of Illinois Urbana-Champaign

Jennifer Moore, Grand Valley State University

Lisa Faust, Lincoln Park Zoo

Disclaimer and photo credits

This page and its contents are not affiliated with any of my current or former employers.

Headshots of Sasha Tetzlaff taken by Kristin Tetzlaff. Photo of Sasha Tetzlaff holding turtles taken by Aron Katz. All other photos taken by Sasha Tetzlaff unless otherwise noted.