About

Dr. Lee A. Fitzgerald is a Professor and Curator at the Biodiversity Research and Teaching Collections (BRTC) at Texas A&M University. He earned his PhD in 1993 from the University of New Mexico. His research focuses on the evolutionary ecology and conservation biology of amphibians and reptiles. As the Principal Investigator of the Fitzgerald Lab, he leads research efforts that explore various aspects of herpetology, including the conservation biology and ecology of species such as Tupinambis lizards and the Dunes Sagebrush Lizard. Dr. Fitzgerald's work integrates research, teaching, extension, and service, contributing to the understanding and preservation of reptile and amphibian biodiversity.

Research topics

• Ecology
• Geography
• Biology
• Environmental resource management
• Computer Science
• Environmental science
• Archaeology
• Fishery
• Cartography
• Evolutionary biology

Selected publications

• Fat reserve and body condition variation in Argentine black and white tegus: native-invasive comparisons and environmental drivers in Florida

  PLoS ONE · 2026-02-11

  articleOpen access

  Invasive species impose major ecological and economic costs on ecosystems and countries where introduced. To effectively manage Argentine black and white tegus (Salvator merianae) within their invasive range, it is important that management actions are based on species' biology. We estimated tegu percentage fat and body condition in native (Cordoba, Argentina) and non-native (South Florida, United States) populations and identified biological, temporal, and environmental variables that influence tegu body condition in South Florida. Large adult tegus in Cordoba had larger fat reserves than tegus in South Florida. However, body condition values were highly similar between the native and non-native range throughout the year, showing a well-adapted tegu population to South Florida environmental conditions. Generalized additive mixed models (size estimate = 2.67) showed very strong (p-value < 0.001) to moderate (p-value <0.01) evidence of Julian day, minimum temperature, and percentage fat individually affecting tegu body condition in South Florida (deviance explained 37%). The direction and magnitude of univariate effects varied from positive linear relationship (minimum temperature) impacting body condition up to 18% to negative (Julian day) and positive (percentage fat) monomodal relationships impacting body condition up to 24% and 6%, respectively. Our results provide insights as to how adaptable tegus are physiologically to novel environments and their capability to maintain body condition that is similar to, or better than that of native individuals. These findings can inform management in Florida by identifying seasonal windows when tegus' activity and condition may make them more susceptible to targeted removal.

  PublisherDOI

• The future for reptiles: Advances and challenges in the Anthropocene

  Elsevier eBooks · 2026-01-01

  book-chapter1st authorCorresponding
  PublisherDOI

• Introduced species are a global threat to lizard biodiversity

  SSRN Electronic Journal · 2026-01-01

  preprintOpen accessSenior author
  PublisherDOI

• Introduced species are a global threat to lizard biodiversity

  Biological Conservation · 2026-04-02

  articleOpen accessSenior author

  Invasive species are a major cause of vertebrate extinctions worldwide, yet there is limited research on their impacts to global patterns of extinction and endangerment in reptiles. We assessed the relative impact of invasive species to extinction risk in native lizards, identified major invasive genera and threat types (e.g., mammalian predator), and examined geographic and ecological correlates of invasive-driven extinction risk using IUCN Red List data. We found that invasive species are the fourth most recorded threat to lizard species yet included the largest number of extinct lizard species of any threat type ( N = 15). An additional 27 species are possibly extinct, indicating that this impact may be substantially greater. At least 128 invasive genera impact native lizards including plants, mammals, reptiles, birds, amphibians, and invertebrates through predation, competition, habitat disruption and/or hybridization. Invasive mammalian predators, especially cats and rats, were the most common threats and associated with most extinctions. Islands were significantly more likely to contain threatened or extinct lizard species, with pronounced hotspots in the Caribbean and Oceania. Deforestation and mammalian habitat disruptors were correlated with significantly higher threat categories for invasive-impacted lizards, while anthropogenically modified landscapes and threats from reptile species were associated with lower extinction risk. Our results place research on invasive-native interactions on lizards into a global context to better understand large-scale patterns. Invasive species currently function as the largest driver of lizard extinction, so management should focus on targeted prevention and control in at-risk hotspots to mitigate this significant threat to global biodiversity.

  PublisherDOI

• Cross‐Continental Analysis Shows That Disturbance Effects on Reptile Body Condition Do Not Predict Abundance Responses

  Global Change Biology · 2025-07-01 · 1 citations

  articleOpen access

  Ecological disturbances are discrete events that alter or transform the physical, chemical, or biological characteristics of ecosystems. Disturbance can cause animal populations to decline and, according to the risk-disturbance hypothesis and population collapse framework, these declines can be predicted by declines in animal body condition. However, no research has empirically examined the general relationship between body condition and abundance, nor their relationship in response to disturbance. We used a combined dataset representing 33 studies and > 42,000 observations of 75 species from Australia, New Zealand, Spain and the United States of America to test predictions relating to the relationship between reptile body condition and abundance. We first investigated the relationship at the site level and then used meta-analytical models to test whether populations showed linked changes in abundance and body condition in response to disturbance. We further tested whether key environmental and species traits influenced this relationship and whether there was a time-lagged effect of body condition responses on abundance. We found a positive relationship between mean reptile body condition and abundance at the site level. However, the relationship was largely lost when investigating population responses to disturbance. As such, our results provided no support for the risk-disturbance hypothesis and limited support for the population collapse framework. Therefore, the impacts of disturbance on reptile body condition cannot be assumed to reflect or predict abundance responses. We provide a new conceptual framework that shows how disturbances can modify or uncouple the relationship between abundance and body condition by influencing underlying drivers, such as predation, competition and resource availability. Monitoring programs that infer population impacts based on changes in body condition should first confirm the relationship between these two variables in the relevant study system.

  PublisherOA PDFDOI

• Conspecific Oophagy by Tadpoles: Conditions for Its Occurrence and Importance as a Source of Anuran Egg Mortality

  Journal of Herpetology · 2025-08-14

  articleSenior author

  The prevailing view of tadpoles as mostly herbivorous organisms is changing with multiple reports of carnivory and ontogenetic, spatial, and temporal changes in tadpole diet. One increasingly recognized aspect of tadpole diet is conspecific oophagy of living fertilized eggs. As reports of this behavior accumulate, patterns remain unanalyzed, and implications for population dynamics remain unexplored. We reviewed reports of conspecific oophagy by tadpoles and found that the behavior is taxonomically, phylogenetically, and regionally widespread, with reports worldwide, except Africa, and across 13 families. Additionally, we report the first observations of conspecific oophagy in threatened Chiricahua Leopard Frogs (Rana chiricahuensis). Conspecific oophagy is predominantly reported in species using ephemeral lentic environments, with cannibalistic tadpoles predominantly in advanced developmental stages (Gosner stages 31–38). We found that species engaging in conspecific oophagy share similar reproductive and larval traits, with a few intriguing outliers including R. chiricahuensis and other leopard frogs. We observed conspecific oophagy in R. chiricahuensis in the wild and assessed its effects by monitoring egg masses and evaluating the relative importance of conspecific tadpole abundance and size in predicting egg mass mortality. The size of nearby conspecific tadpoles was the only statistically significant predictor of egg mass survival. Our results underscore the importance of ontogenetic diet changes in tadpole development, which facilitate conspecific oophagy.

  PublisherDOI

• 43 EXPLORING THE WILD KINGDOM WITH MARLIN

  Cornell University Press eBooks · 2024-04-23

  book-chapter1st authorCorresponding
  PublisherDOI

• Exploring the Wild Kingdom With Marlin

  Cornell University Press eBooks · 2024-04-15

  book-chapter1st authorCorresponding

  This chapter discusses the work of Peace Corps volunteers (PCVs) in Paraguay with the Wild Kingdom. It looks into the establishment of the National Biological Inventory following organized scientific collecting expeditions since the Paraguay Expedition of 1858 and the contributions of Moises Santiago Bertoni. The Servicio Nacional Forestal and Peace Corps had been contacted by Mutual of Omaha's Wild Kingdom TV show, starring Marlin Perkins. Perkins was an excellent and well-respected herpetologist since he was the curator at the Chicago Zoo and then the St. Louis Zoo, where he influenced his field and inspired many people. The chapter then provides an insight into the filming of the Wild Kingdom.

  PublisherDOI

• Using life history to predict outcomes of conservation translocations of herpetofauna

  Animal Conservation · 2024-12-19 · 2 citations

  articleOpen accessSenior author

  Abstract Suites of coevolved traits related to reproduction and demography enable species to persist in the face of environmental change. In the case of biological invasions, the suite of life history traits, “life history strategies,” can be linked to successful establishment after an introduction. Conservation translocations share many similarities with biological invasions, yet studies examining the relationship between life history and translocation outcome are scarce. We collected data on key life history traits for all herpetofauna profiled in the IUCN Global Conservation Translocation Perspectives series to examine how life history can predict outcomes and difficulties of conservation translocations. For reptiles, our model showed that age at maturity showed a significant positive association with higher probabilities of more successful outcomes, while increased clutch/litter size and lifespan predicted less successful outcomes. We found no relationship between any life history trait and translocation outcome for amphibians. Our results showed that difficulties with conservation translocations are related more to phylogeny than life history. Amphibian translocations faced more difficulties due to the physical environment of release sites, but reptile translocations experienced more socio‐political difficulties. These relationships provide important insights for conservation practitioners that can be used in the feasibility and planning stages of translocations to anticipate and avoid challenges facing this complex and increasingly common form of conservation intervention.

  PublisherOA PDFDOI

• Where the toad crosses the road: multi-method and cross-taxa Texas herpetofauna roadkill modeling for conservation planning

  Biodiversity and Conservation · 2024-04-22 · 3 citations

  article
  PublisherDOI

Recent grants

• IGERT: Applied Biodiversity Science - Bridging Ecology, Culture, and Governance for Effective Conservation in the Americas

  NSF · $3.0M · 2007–2015

• Recuration and Geo-Referencing of the Herpetological Collection at Texas Cooperative Wildlife Collection

  NSF · $203k · 2005–2008

• CSBR: Ownership Transfer: Rehabilitation and digitization of a significant collection of amphibians, reptiles, and fishes through institutional networking

  NSF · $204k · 2015–2018

Frequent coauthors

• Wade A. Ryberg

  20 shared

• Erin K. Buchholtz

  Texas A&M University

  20 shared

• Amanda Stronza

  Texas A&M University System

  15 shared

• Toby J. Hibbitts

  Texas A&M University

  13 shared

• Kristina Chyn

  Texas A&M University

  12 shared

• Gage H. Dayton

  University of California, Santa Cruz

  12 shared

• Anna Songhurst

  12 shared

• Graham McCulloch

  Botswana Predator Conservation Trust

  12 shared

Labs

• The Fitzgerald LabPI

  Evolutionary ecology and conservation biology of amphibians and reptiles

Education

• B.S., Biology

  Stephen F. Austin State University

• M.S., Biology

  University of New Mexico

• Ph.D., Biology

  University of New Mexico