Current Graduate Students
Below are the individuals in our lab who are currently working towards earning Masters, PhD, and/or DVM.
Sebastian Ortiz, PhD Student
Sebastian has a background on environmental studies and biology. He was part of a study that compared the biodiversity of the Everglades natural and agricultural lands and human-made wetlands in South Florida. He also spent a summer tracking mammals in remnant tracts of the Atlantic rainforest in the state of Minas Gerais, Brazil. Through these experiences he saw first hand the interconnection between human activity and nature as well as the power of the individual to influence the outcome of these interactions. Sebastian is pursuing a PhD in Integrative Conservation and believes in using an interdisciplinary approach and analyzing different points of view to find ways to balance relationships between humans and the natural world. He enjoys being in nature and sharing time with family and friends.
Matthew Tatz, PhD Student
Matt is an Integrative Conservation in Ecology Ph.D. student co-advised by Dr. Sonia Hernandez at the Warnell School of Forestry and Dr. Stacey Lance at the Odum School of Ecology. Matt received his B.S. in Environmental Science with a focus in Ecology from Georgia Gwinnett College (GGC) before obtaining his M.S. in Forestry and Natural Resources (Wildlife Science) at Warnell under Dr. Hernandez. Matt’s passion for conservation and scientific outreach stems from his time conducting avian research. At GGC, Matt published his independent research on feeder bird activity patterns in fragmented forests. At Warnell, he studied the relationship between mercury, urbanization, and Salmonella in the American white ibis (Eudocimus albus). His research interests include conservation science, ecotoxicology, and disease ecology. As he aspires to become a professor, Matt’s favorite aspect of graduate school has been teaching and mentoring undergraduate students.
Doreen Chaussadas, PhD Student
Doreen is fascinated with animal behavior and more particularly animal traditions and cultural evolution. Very early on, she learnt that an interdisciplinary approach was best fit to answer the questions that interest her, which led her to build interest in animal social dynamics and information transmission and their link to adaptation and genetic evolution. She started her research journey by studying vocal dialects in resident groups of Blackcaps (Sylvia atricapilla) during her undergraduate studies at the Université de Paris-Saclay (France). After she got her B.S. in 2015, she started working towards her master’s degree in Ethology, and joined a collaborative research project between the Université de Strasbourg (France) and the University of Cape Town (South Africa), studying the impacts of climate change on the interspecific social structure and information transmission within an avian community in the Kalahari desert. Doreen got her M.S in 2017, after which took a few years to work on various research projects, always focusing on birds and their behavior. In the Hernandez lab, she hopes to understand how the behavioral variations in American White Ibises (Eudocymus albus) provide them with adaptations to their living environment, and to test if these denote the premises of a divergent cultural system that may influence their genetic evolution.
Sarah Dean, Undergraduate Student
Sarah Dean is an undergraduate student interested in disease ecology and One Health. She is pursuing degrees in ecology (B.S.) and microbiology (B.S.) at UGA, and her eventual goal is to obtain a PhD in disease ecology. Her research experience began on Dr. Hernandez’s Conservation Medicine course in Costa Rica, where she studied aggressive behaviors in a native fish and fell in love with the demands and rewards of field work and data analysis. She has since worked with the Hernandez Lab on the White Ibis Project and on a CURO-funded study on avian salmonellosis in bird feeders. She enjoys running, visiting national parks, and coffee.
Kimberly Perez, PhD Student
Kimberly is a PhD student in Environmental Health Science under the advisement of Dr. Erin K. Lipp and Dr. Sonia M. Hernandez. Kimberly recived a BS and BA in Animal Science and Journalism respectively, from Colorado State University and a MPH from UGA. During her MPH, Kimberly assisted Dr. Hernandez with work on antimicrobial resistence in white stork across a natural and landfill use gradient. After this work, she coupled her interest of public health policy with her enthusiasm of wildlife and enteric pathogens and conducted a Salmonella persistence trial on bird feeders under the direction of Dr. Hernandez. Through these experiences, Kimberly took a stronger interest in avian disease dynamics. Kimberly’s current projects explore Salmonella isolation in songbirds and various environs (e.g., feeders).
Raena McCown, PhD Student
​Raena has been enamored by birds ever since she can remember. She grew up in a house with many parrot companions and her love of these feathered friends blossomed into a fascination as she obtained her B.S. in Avian Biology at UGA in 2022. Raena is currently a PhD student Co-advised by Dr. Sonia Hernandez in the Warnell School of Forestry and Dr. Andrew Benson in the Department of Poultry Science. She is interested in the ecological physiology and urban ecology of Passeriformes, with a focus on how different conditions during avian oogenesis and embryogenesis can impact offspring fitness. Raena’s favorite bird would have to be the Eastern bluebird, as she does research on the wild population in Athen’s, Georgia.
Tobias Haymes, PhD Student
Tobias is a PhD student in Forestry and Natural Resources with an emphasis in Wildlife Sciences co-advised by Dr. Sonia Hernandez and Dr. Claire Teitelbaum. A returning two-time UGA graduate, he earned a bachelor’s degree in Fisheries and Wildlife in 2022 and completed his M.S. in Forestry and Natural Resources (Wildlife Sciences) in 2025. His master's research focused on the “eagle-killer toxin” known as aetokthonotoxin (AETX) and its associated disease – vacuolar myelinopathy (VM). Specifically, Tobias was interested in how AETX affects mammals, and whether it was linked to neurologic diseases in predators and scavengers. During his time as a student, Tobias has worked for the UGA deer research lab, been a student contractor for USGS, and assisted with white-tailed deer fawn research in south Texas. He has also been a teaching assistant for several Warnell courses including spatial analysis, aquatic biology, and wildlife techniques. Tobias hopes to continue researching the ecosystem-level effects of AETX and other toxins by collaborating with state and federal researchers. He is broadly interested in all things related to wildlife disease ecology and ecotoxicology, and is perusing a PhD to aid his goal of working in higher education.
Justin Whitening, MNR Student
Justin is a first-year Master’s of Natural Resources (MMNR) student working under Dr. Sonia Hernandez at the Warnell School of Forestry and Natural Resources. He graduated with an Associate’s Degree in Arts & Sciences at Oxford College of Emory University in 2023 and with a Bachelor’s Degree of Science at Emory University in 2025. Justin is most interested in animal science with implications to human health. While he does not have a specific research project at the current moment, he is actively seeking research opportunities in the biological sciences on campus.