About

Toby Hibbitts works as the curator of amphibians and reptiles at the Biodiversity Research and Teaching Collection at Texas A&M University. His research program focuses on amphibians and reptiles, with interests in natural history, ecology, behavior, and taxonomy. These areas are important for making informed conservation decisions about species. He joined the Texas A&M Natural Resources Institute as a research scientist in 2012. Hibbitts holds a Bachelor of Science in biology from Midwestern State University, a Master of Science in wildlife and fisheries sciences from Texas A&M University, and a doctorate in animal, plant and environmental science from the University of the Witwatersrand. Coming from a family of Texas naturalists, he enjoys outdoor sporting activities and travel.

Research topics

• Biology
• Ecology
• Machine Learning
• Computer Science
• Artificial Intelligence
• Geography
• Fishery
• Mathematics

Selected publications

• Terrestrial and Aquatic Site Fidelity in Western Chicken Turtles (Deirochelys reticularia miaria)

  Southeastern Naturalist · 2026-01-05

  article

  Characterizing fidelity to refugia sites is important for conservation of semiaquatic taxa like turtles, as development near aquatic habitat such as wetlands can decrease survivorship in species that exhibit site-fidelity behavior. This study quantified terrestrial aestivation-site fidelity and examined demographic differences in aquatic site fidelity among Deirochelys reticularia miaria (Western Chicken Turtle) in Texas. Using telemetry and mark–recapture data, we measured fidelity to aestivation sites through 2 metrics: minimum bearing widths from the last wetland visited and mean pairwise distances among aestivation sites. Individuals showed directional similarity in movement to, and clustering of, terrestrial sites, with population mean pairwise distances indicating terrestrial site fidelity. Aquatic site fidelity varied by age, with juveniles using only 1 wetland, and mature individuals using up to 7. These findings emphasize the need to protect upland buffers around wetlands occupied by Western Chicken Turtles due to high terrestrial fidelity. Additionally, demographic differences in aquatic site fidelity should be considered in monitoring and population modeling in this species to avoid misinterpreting adult emigration as high mortality.

  PublisherDOI

• Phylogenetic structure of Holbrookia lacerata (Cope 1880) (Squamata: Phrynosomatidae): one species or two?

  The Catalogue of Life · 2026-02-17

  datasetOpen access1st authorCorresponding
  PublisherDOI

• Whole genome resequencing data provide high-resolution conservation insights into population structure and life history

  Conservation Genetics · 2026-04-30

  articleOpen access

  Abstract Whole genome resequencing can be a powerful tool for uncovering biological insights and quantifying population genomic metrics relevant to conservation. These insights have the potential to be most profound in secretive or elusive species that are understudied but whose populations may be waning. The western chicken turtle ( Deirochelys reticularia miaria ) is one such example where conservationists are concerned about reported population declines. Here, we report results from analyses of genome sequence data from western chicken turtles and how the associated inferences could be used to inform management decisions. We sequenced and assembled a novel reference genome, then conducted a population genomics resequencing survey across much of Texas that represents one of the first in any freshwater turtle. We uncovered fine-scale population structure indicative of natal philopatry. Absolute values of fixation indices were relatively small (all pairwise F ST $$\:\le\:$$ 0.03), but principal component analyses of the resequencing data readily separated individuals into clusters that correspond to their geographic sampling sites (i.e., wetland mosaic) and phylogenomic analyses revealed monophyletic groupings that also correspond to wetland mosaic geography. Estimates of individual genome-wide heterozygosity ( H ) were similar to those observed for threatened or endangered turtle species. Collectively, our data suggest that western chicken turtle populations are spatially differentiated due to natal philopatry and limited gene flow. We discuss the relevance of these insights as they pertain to turtle biology, including the conservation implications of philopatry in a species of concern.

  PublisherDOI

• Phylogenetic structure of Holbrookia lacerata (Cope 1880) (Squamata: Phrynosomatidae): one species or two?

  The Catalogue of Life · 2026-02-16

  datasetOpen access1st authorCorresponding
  PublisherDOI

• Habitat use of the Texas Alligator Lizard ( <i>Gerrhonotus infernalis</i> ) in Central Texas

  Journal of Natural History · 2025-05-08

  articleSenior author
  PublisherDOI

• Integrating ensemble habitat suitability models to guide conservation strategies for the endangered Houston toad Anaxyrus houstonensis

  Endangered Species Research · 2025-05-15

  articleOpen access

  The Houston toad Anaxyrus houstonensis , an amphibian endemic to eastern-central Texas, was one of the first amphibians to be listed as federally endangered in the USA. Despite ongoing conservation efforts, the species continues to face declining populations from habitat degradation, loss, and fragmentation, along with compounding effects of climate change and increased drought severity. This study aimed to develop robust habitat suitability models for A. houstonensis using ensemble habitat suitability modeling (EHSM) to inform conservation strategies. We generated multiple EHSMs to identify suitable habitats, potential survey sites, and reintroduction areas, integrating occurrence data from various sources with environmental and climatic variables. We also conducted connectivity modeling to highlight essential habitat corridors that could enhance population dispersal and interconnectivity. Our models indicate that deep sandy soils, forest cover, and maximum precipitation in March are critical factors associated with use by A. houstonensis , reinforcing prior understanding of A. houstonensis habitat needs. Our model projections showed there has been a loss of 23% of the top-quality habitat between 2004 and 2021. However, the lack of connectivity among the core patches suggests that restoring the historical species connectivity is an unlikely event, and that we should focus on increasing connectivity within the large core patches. These findings provide crucial guidance for targeted habitat conservation, restoration efforts, and land management practices. Moving forward, these models will be instrumental in refining recovery plans, engaging stakeholders, and identifying target areas for priority conservation actions, outlined in the 2022 A. houstonensis recovery plan.

  PublisherDOI

• Camera Trap Surveys Characterize a Snake Community from a Chihuahuan Desert Shortgrass Prairie

  Western North American Naturalist · 2024-11-22 · 1 citations

  article

  Los pastizales del Desierto Chihuahuense son ecológicamente diversos y se consideran uno de los ecosistemas más amenazados en América del Norte, extendiéndose desde el suroeste de los Estados Unidos hasta San Luis Potosí, en México. Estos pastizales desérticos albergan una amplia diversidad de especies de mamíferos, aves y herpetofauna, siendo esta última uno de los grupos menos estudiados dentro de estos ecosistemas. Los datos acerca de las comunidades de serpientes dentro de los pastizales desérticos son relativamente escasos debido a la dificultad para detectar de manera consistente a estos sigilosos reptiles. En este artículo, registramos el éxito de las cámaras trampa activadas por intervalos de tiempo, en la documentación de la estructura de la comunidad de serpientes dentro de un ecosistema de pastizal desértico de pasto corto, en un área de propiedad privada en la región de TransPecos de Texas, en el condado de Presidio. Durante los años 2020 y 2021, se capturaron un total de 564 imágenes de serpientes, de las cuales 268 fueron observaciones únicas que representaron 15 especies. Se observaron serpientes durante cada uno de los meses que las cámaras estuvieron en funcionamiento, con excepción de los meses de febrero y noviembre del 2020. Los índices de diversidad fueron similares entre las distintas cámaras, pero la frecuencia de ocurrencia de cada especie varió enormemente. La cámara trampa continúa desempeñando un papel fundamental en la caracterización de comunidades de escamosos, y este estudio brinda otro ejemplo de cómo el uso de cámaras trampa puede contribuir en el estudio de comunidades de serpientes en áreas de propiedad privada dentro de los ecosistemas de pastizal desértico.

  PublisherDOI

• Morphology and vocalization comparison of the Houston Toad and the Dwarf American Toad: implications for their historic range

  PeerJ · 2024-07-08 · 1 citations

  articleOpen access

  Documenting changes in the distribution and abundance of a given taxon requires historical data. In the absence of long-term monitoring data collected throughout the range of a taxon, conservation biologists often rely on preserved museum specimens to determine the past or present, putative geographic distribution. Distributional data for the Houston Toad ( Anaxyrus houstonensis ) has consistently been confounded by similarities with a sympatric congener, the Dwarf American Toad ( A. americanus charlesmithi ), both in monitoring data derived from chorusing surveys, and in historical data via museum specimens. In this case, misidentification can have unintended impacts on conservation efforts, where the Houston Toad is federally endangered, and the Dwarf American Toad is of least concern. Previously published reports have compared these two taxon on the basis of their male advertisement call and morphological appearance, often with the goal of using these characters to substantiate their taxonomic status prior to the advent of DNA sequencing technology. However, numerous studies report findings that contradict one another, and no consensus on the true differences or similarities can be drawn. Here, we use contemporary recordings of wild populations of each taxon to test for quantifiable differences in male advertisement call. Additionally, we quantitatively examine a subset of vouchered museum specimens representing each taxon to test previously reported differentiating morphometric characters used to distinguish among other Bufonids of East-Central Texas, USA. Finally, we assemble and qualitatively evaluate a database of photographs representing catalogued museum vouchers for each taxon to determine if their previously documented historic ranges may be larger than are currently accepted. Our findings reveal quantifiable differences between two allopatric congeners with respect to their male advertisement call, whereas we found similarities among their detailed morphology. Additionally, we report on the existence of additional, historically overlooked, museum records for the Houston Toad in the context of its putative historic range, and discuss errors associated with the curation of these specimens whose identity and nomenclature have not been consistent through time. These results bookend decades of disagreement regarding the morphology, voice, and historic distribution of these taxa, and alert practitioners of conservation efforts for the Houston Toad to previously unreported locations of occurrence.

  PublisherOA PDFDOI

• Spatial Ecology of the Texas Alligator Lizard (Gerrhonotus infernalis) in Blanco County, Texas

  Western North American Naturalist · 2023-10-11 · 1 citations

  articleSenior author

  El Cantil de Tierra (Gerrhonotus infernalis) se distribuye desde la parte central del estado de Texas en los Estados Unidos, hasta la zona fronteriza del Noreste de México. La información ecológica publicada formalmente sobre sus patrones de movimiento tanto arbóreos como terrestres es muy escasa y con la finalidad de proveer información ecológica básica sobre las poblaciones existentes en la parte mas al norte de su rango de distribución natural, hemos utilizado radiotelemetria para analizar el área de distribución anual y la actividad arbórea de G. infernalis en Bamberger Ranch Preserve, en el condado de Blanco, Texas. De movimiento en G. infernalis fueron influenciados por señales ambientales (estaciones) y de comportamiento (periodo de reproducción), pero en términos generales, no se encontraron diferencias entre sexos. El rango anual de distribución espacial fue variable y los machos promediaron un mayor uso total del espacio, mientras que las hembras promediaron un uso mayor de sus áreas de preferencia, aunque dicha diferencia no fue significativa. Machos y hembras presentaron hábitos arbóreos similares, aunque vale destacar que la actividad arbórea presento variaciones estacionales y también durante el periodo diurno. La mayoría de la actividad arbórea ocurrió durante el verano y el fin de la primavera, mostrando una reducción en el final del otoño y el invierno. En promedio, G. infernalis utilizo sitios de percha más altos durante las últimas horas de la tarde y las primeras horas de la mañana. Los sitios de percha de menor elevación fueron utilizados durante las primeras horas de la tarde. Los resultados de esta investigación proveen información novedosa acerca de la ecología de la especie en la parte central del estado de Texas y favorecen el desarrollo de nuevas acciones de manejo para la especie.

  PublisherDOI

• Distribution and Demography of the Alligator Snapping Turtle (Macrochelys temminckii) in Texas: A 20-Year Perspective

  Southeastern Naturalist · 2023 · 8 citations

  • Geography
  • Fishery
  • Ecology

  Texas contains the southwestern range edge of Macrochelys temminckii (Alligator Snapping Turtle), but there is relatively little published information on this species within the state. To document its range and assess temporal changes in its distribution and demography, we sampled 23 sites from 1999 to 2001. We then resurveyed 22 of these sites and sampled 29 additional sites in 2020–2021. Detection outcomes were consistent between 18 of the 22 resurveyed sites. Sex ratios and body-size distributions were similar across surveys. Catch per unit effort (CPUE) was lower in areas with trotlines, corroborating known interactions between turtles and fishing gear. Patterns in CPUE indicate Gulf of Mexico-draining watersheds are important systems for the species, while CPUE was lower in Mississippi-draining watersheds.

  PublisherDOI

Frequent coauthors

• Wade A. Ryberg

  32 shared

• Troy D. Hibbitts

  25 shared

• Travis J. LaDuc

  18 shared

• Danielle K. Walkup

  Texas A&M University

  16 shared

• Lee A. Fitzgerald

  13 shared

• Connor S. Adams

  13 shared

• Jon Paul Pierre

  The University of Texas at Austin

  10 shared

• Brad D. Wolaver

  Bureau of Economic Analysis

  10 shared

Labs

• Animal Behavior LabPI

Education

• B.S.

  Midwestern State University

• M.S., wildlife and fisheries sciences

  Texas A&M University

• Ph.D., animal, plant and environmental science

  University of the Witwatersrand