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Thane Wibbels headshot.

Professor, Undergraduate Honors Program Director This email address is being protected from spambots. You need JavaScript enabled to view it.
3132 East Science Hall, Science & Engineering Complex
(205) 934-4419

Research and Teaching Interests: Zoology, Physiology, Evolution, Conservation, Ecology, Conservation of Marine Turtles with an Emphasis on Temperature-Dependent Sex Determination

Office Hours: By appointment


  • B.S., University of Nebraska, Zoology
  • M.S., University of Houston, Biology, Marine Science Program
  • Ph.D., Texas A&M University, Zoology

I developed an intense interest in marine biology during my undergraduate studies, which led me to the Marine Science graduate program at the University of Houston, located on the National Marine Fisheries Service (NMFS) base in Galveston. NMFS was part of an international program trying to prevent the extinction of the critically endangered Kemp’s ridley sea turtle, and was “headstarting” about 2,000 turtles per year in Galveston. I quickly became involved in that project and studied their behavior and conservation for my thesis. During that time I began appreciating the unique biology of sea turtles and became acutely aware of how important conservation was to the survival of endangered species.

To further pursue this interest I joined a Ph.D. program at Texas A&M under the guidance of Dave Owens (an expert on sea turtle biology and reproduction). Due to Dave’s insight, my general interest in sea turtles and biology expanded greatly as I realized that sea turtles were a prime example of vertebrate physiology, ecology, and evolution. Additionally they had a long-term history/interaction with humans, with historical exploitation and, more recently, intense conservation. We studied loggerhead sea turtles in Florida and olive ridley sea turtles in Mexico; then we obtained an NSF grant that allowed us to travel to the Great Barrier Reef (GBR) to conduct a collaborative study with Colin Limpus (Australia’s leading sea turtle expert). For six months we lived on a small island and studied the reproductive endocrinology and ecology of sea turtles. We would go out daily on the GBR and capture, tag, obtain blood samples, and even laparoscopy turtles ranging from small juveniles to giant adults. During the study we captured approximately 900 turtles, used those data to evaluate the hormones controlling reproduction in adults, and validated hormone-based sexing techniques for juveniles.

After that I completed a postdoctoral fellowship and an NIH National Research Service Award, shifting from studying adult reproduction of turtles to how sex is determined in turtles that have temperature-dependent sex determination (TSD). This also meant that I went from catching giant sea turtles on the GBR to studying the physiology of sex determination in the basement of the Zoology building at the University of Texas at Austin. TSD is a fascinating area of study and has significant implications for the biology, ecology, evolution, and conservation of reptiles, including endangered sea turtles. I was fortunate to be able to complete the postdoctoral fellowship under the guidance of David Crews and Jim Bull, two world-renowned scientists. During that project we developed the red-eared slider turtle as a model system for studying the physiology of TSD in turtles.

Since coming to UAB I have continued an active research program focusing on basic scientific questions using marine turtles as the model system. Most recently we have been examining the biology of marine turtles in relationship to global climate change. The results of these studies are providing basic information on sea turtle ecology, evolution, and conservation, and they are revealing that sea turtles are an excellent vertebrate model system for studying the impact of global climate change.

  • Research Interests

    My research interests center on the biology, ecology, evolution, and conservation of marine turtles with an emphasis on temperature-dependent sex determination (TSD). The research that my students and I are conducting is multidisciplinary and includes field research with conservation programs for marine turtles, as well as laboratory studies on the physiology underlying TSD.

    In regards to marine turtle conservation, we work with sea turtles and with the diamondback terrapin, a turtle that inhabits bays and salt marshes. We are currently studying its biology and developing a recovery strategy for this depleted species in Alabama. This includes the evaluation of a “headstart program” for the terrapin. We are also collaborating with a variety of state, federal, and international agencies on conservation programs for sea turtles. In these studies we are generating long-term databases for nesting beach temperatures that affect TSD, and we are evaluating hatchling sex ratios resulting from TSD. This includes studies of the Kemp’s ridley sea turtle in Mexico, the hawksbill sea turtle in the Caribbean, and the leatherback sea turtle in the Pacific. Of particular significance, we have been involved in with the Binational Kemp’s ridley recovery program for almost two decades, and have been helping facilitate the survival and recovery of this critically endangered sea turtle.

    Our physiological studies focus on TSD, in which the sex of many reptiles is determined by the temperature at which the egg is incubated. TSD provides several advantages not available in other vertebrate sex determination systems, including the ability to manipulate sex by both temperature and steroid hormones. We are using the slider turtle as a model system for elucidating the physiology underlying sex determination and gonadal differentiation. The results have implications for both the biology and conservation of endangered turtles.

    Finally, our long-term studies of sea turtle reproduction, sex determination, and sex ratios are revealing that sea turtles represent an optimal vertebrate model system for examining the impact of long-term changes in environmental temperature. In particular, their reproductive timing, sex determination, and embryonic development are all temperature sensitive. Thus they are extremely sensitive to thermal changes in the environment, making them an ideal “sentinel” species for examining the impact of global climate change.

  • Recent Courses
    • BY 256: Vertebrate Zoology — provides a broad overview of vertebrates, including a strong emphasis on their evolution, biology, ecology, and conservation. It is targeted at giving students an in-depth appreciation of the amazing diversity of vertebrates in the animal kingdom and how they fit into nature.
    • BY 409: Principles of Human Physiology — provides an in-depth overview of human physiology, examining each of the major physiological systems. BY 409 is targeted at pre-medical and pre-veterinary students in order to give them a comprehensive knowledge of human physiology, and to better prepare them for postgraduate professional schools and for the MCAT, DAT, OAT, and GRE exams.
  • Graduate Students

    Current Students

    • Amy Bonka, Ph.D. Candidate. Dissertation Topic: Ecology and evolution of early life history events in sea turtles.
    • Nicole Conner, M.S. Candidate. Thesis Topic: Development of new technologies for studying the ecology and conservation status of the diamondback terrapin.
    • Catherine Sirgo, M.S. Candidate. Impact of global climate change on the biology and conservation status of the diamondback terrapin in Alabama.
    • Forrest Collins, M.S. Program. Application of stable isotope and genetic technologies for understanding the ecology of the diamondback terrapin in a saltmarsh ecosystem in Alabama.
  • Select Publications
    • Wibbels, T. and E. Bevan (2019). IUCN Red List Assessment of the Conservation Status of the Kemp’s Ridley Sea Turtles. (IUCN, Morges, Switzerland).
    • Steele, A., Wibbels, T., and Warner, D.(2018). Revisiting the first report of temperature-dependent sex determination in a vertebrate, the African redhead agama Journal of Zoology 306: 16 – 22.
    • Wibbels, T., Roberge, T., and Place, A. (2018). Temperature-Dependent Sex Determination in the Diamond-Backed Terrapin (Malaclemys terrapin). In: Biology of the Diamond-Backed Terrapin (W. Roosenburg and V. Kennedy, eds). John Hopkins University Press. Pp 127 – 145.
    • Wibbels, T. and Bevan, E. (2018). Conservation Status of the Kemp’s Ridley Sea Turtle World Wide. In: State of the World’s Sea Turtles. 13: (32 - 33 pp).
    • Rees, A.F. et al (24 authors including T. Wibbels), (2018). The potential of unmanned aerial systems for sea turtle research and conservation: a review and future directions. Endangered Species Research 35: 81-100.
    • Wibbels, T. and E. Bevan. (2016) Historical perspective of the biology and conservation of the Kemp’s ridley sea turtle. Gulf of Mexico Science, 2016 (2): 129-137.
    • Gallaway, B. J., W. J. Gazey, D. Shaver, T. Wibbels, and E. Bevan. Evaluation of the status of the Kemp’s ridley sea turtle following the 2010 Deepwater Horizon oil spill. Gulf of Mexico Science, 2016 (2) 192 -205.
    • Bevan, E., T. Wibbels, E. Navara, M. Rosas, B.M.Z. Najera,L. Sarti, F.I. Martinez, J.M. Cuevas, B. L.J. Pena, and P.M. Burthfield. (2016). Using Unmanned Aerial Vehicle (UAVs) Technology for Locating, Identifying, and Monitoring Courtship and Mating Behavior in the Green Turtle (Chelonia mydas) Herpetological Review 47: 27-32.
    • Gallaway, B.J., W.J. Gazey, C.W. Caillouet, Jr., P. Plotkin,, F.A. Abreu Grobois, A.F. Amos, P.M. Burchfield, R.R. Carthy, M.A. Castro Martinez, HJ.G. Cole, A.T. Coleman, M. Cook, S. DiMarco, S.P. Epperly, M. Fujiwaraa, D. Gomez Gomez, G.L. Graham, W.L. Griffin, F. Illescas Martinez, M.M. Lamont, R.L. Lewison, K.J. Lohmann, J.M. Nance, J. Pitchford, N.F. Putman, S.W. Raborn, J.K. Rester, J.J. Rudloe, L. Sarti Martinez, N. Schemayder, J.R. Schmid, D.J. Shaver, C. Slay, A.D. Tucker, M. Tumlin, T. Wibbels and B.M. Zapata Najera. 2016. Development of a Kemp’s ridley sea turte stock assessment Model. Gulf of Mexico Science 33: 1-20.
    • Bevan, E., T. Wibbels, B.M.Z. Najera, L. Sarti, F.I. Martinez, J.M. Cuevas, B. Gallaway, L.J. Pena, and P.M. Burthfield. (2016). Estimating the historic size and current status of the Kemp’s ridley sea turtle (Lepidochelys kempii) population. Ecosphere 7: 1-15.
    • Wibbels, T. and Bevan, E. (2015). Another riddle in the ridley saga. In: State of the World’s Sea Turtles. 10: (15-17 pp).
  • Academic Distinctions and Professional Societies
    • 2019 – 2020 Vice President, Southeast Regional Sea Turtle Network.
    • 2018 – 2019 Invited member; NOAA Fisheries Sea Turtle Climate Vulnerability Assessment Team
    • 2016 Lifetime Achievement Award, Southeast Regional Sea Turtle Symposium, Feb, 2016.
    • 1989-present: Invited Member of the International Union for the Conservation of Nature (Gland, Switzerland), Species Survival Commission, Marine Turtle Specialist Group, invited to complete Kemp’s Ridley Red List Assessment (2014-2015)
    • Invited Member of the Kemp’s Ridley Working Group that oversees and plans conservation research and strategy for the recovery of this critically endangered sea turtle, 1998-present.
    • Member of the Board of Directors, International Sea Turtle Society, 2005-2008.
    • Invited by US Fish and Wildlife Service to write the five-year review evaluating the survival status of the Kemp’s ridley sea turtl, 2007
    • President, International Sea Turtle Society, 2004/2005
    • Teaching Awards: UAB Presidents Award for Teaching Excellence, UAB Early Medical Acceptance Program Teaching Award, Finalist for UAB’s Ingall’s Award for Teaching Excellence UAB Dean’s Award for Excellence in Mentorship
    • National Awards/Fellowships to Graduate Students
    • Anne Marie LeBlanc Eich: NOAA Knauss Fellowship
    • Andrew Coleman: NOAA Knauss Fellowship
    • Elizabeth Bevan: NOAA Knauss Fellowship
  • Student Groups
    • Chair, Undergraduate Honors Program in Biology
    • Sponsor, UAB Department of Biology Marine and Field Biology Club
    • Sponsor, UAB Korean Soccer Club