About

Travis Gallo is an Assistant Professor in the Department of Environmental Science & Technology at the University of Maryland. His research focuses on environmental science and technology, contributing to the understanding and management of ecological and environmental systems. Based at the College of Agriculture & Natural Resources, he is involved in advancing knowledge in areas related to environmental health, sustainability, and resource management. His work supports the college's broader initiatives to improve human, animal, and environmental health, as well as to promote sustainable agricultural and environmental practices.

Research topics

• Geography
• Ecology
• Biology
• Sociology
• Demography
• Environmental science
• Environmental resource management
• Environmental planning
• Economic geography

Selected publications

• Integrating human mobility and animal movement data reveals complex space-use between humans and white-tailed deer in urban environments

  Scientific Reports · 2025-05-27 · 2 citations

  articleOpen access

  Human expansion into wildlife habitats has increased the need to understand human-wildlife interactions, necessitating interdisciplinary approaches to assess zoonotic disease transmission risks and public health impacts. This study integrated fine-grained human foot traffic data with hourly GPS data from 38 white-tailed deer (Odocoileus virginianus), a species linked to SARS-CoV-2, brucella, and chronic wasting disease, in Howard County, Maryland. We explored spatial and temporal overlap between human and deer activity over 24 months (2018-2019) across a hexagonal tessellation with metrics like hourly popularity and visit counts. Negative binomial models were fitted to the visit counts of each deer and humans per tessellation area, using landscape features as predictors. A separate deer-only model included commercial human activity as another predictor. Spatial analysis showed deer and humans sharing spaces in the study area, with results indicating deer using more populated residential areas and areas with commercial activity. Temporal analysis showed deer avoiding commercial spaces during daytime but using them in late evening and early morning. These findings highlight the complex space use between species and the importance of integrating detailed human mobility and animal movement data when managing wildlife-human conflict and zoonotic disease transmission, particularly in urban areas with a high probability of deer-human interactions.

  PublisherDOI

• <scp>SNAPSHOT USA</scp> 2019–2023: The First Five Years of Data From a Coordinated Camera Trap Survey of the United States

  Global Ecology and Biogeography · 2025-01-01 · 12 citations

  article

  ABSTRACT Motivation SNAPSHOT USA is an annual, multicontributor camera trap survey of mammals across the United States. The growing SNAPSHOT USA dataset is intended for tracking the spatial and temporal responses of mammal populations to changes in land use, land cover and climate. These data will be useful for exploring the drivers of spatial and temporal changes in relative abundance and distribution, as well as the impacts of species interactions on daily activity patterns. Main Types of Variables Contained SNAPSHOT USA 2019–2023 contains 987,979 records of camera trap image sequence data and 9694 records of camera trap deployment metadata. Spatial Location and Grain Data were collected across the United States of America in all 50 states, 12 ecoregions and many ecosystems. Time Period and Grain Data were collected between 1st August and 29th December each year from 2019 to 2023. Major Taxa and Level of Measurement The dataset includes a wide range of taxa but is primarily focused on medium to large mammals. Software Format SNAPSHOT USA 2019–2023 comprises two .csv files. The original data can be found within the SNAPSHOT USA Initiative in the Wildlife Insights platform.

  PublisherDOI

• Returning neighbors: eastern wild turkey ( <i>Meleagris gallopavo silvestris</i> ) occupancy in an urban landscape

  Journal of Wildlife Management · 2025-10-14

  articleOpen accessSenior authorCorresponding

  Abstract Once extirpated from most of its range because of overharvest and habitat loss in the early 1900s, the eastern wild turkey ( Meleagris gallopavo silvestris ) has been recolonizing landscapes in the eastern United States following restoration and reintroduction efforts. Wild turkey populations have rebounded in the last 50 years, and the wild turkey is now seen as one of the most successful conservation efforts in the United States. More recently, wild turkeys have begun to expand into cities across the United States. While this can be seen as a successful return of a once‐extirpated species, it has also given rise to human–wildlife conflict in highly populated areas. Given the ecological differences between urban and rural ecosystems, it is important for conservation and management efforts to understand how wild turkeys use urban landscapes. We used cameras deployed at 75 long‐term study sites across the Washington, D.C. region to assess occupancy and habitat use of urban wild turkeys at multiple scales. We found that wild turkey occupancy was positively correlated with the distance to roadways and the proportion of natural vegetation cover within 1 km, whereas occupancy was negatively correlated with the distance to the nearest water source and mean canopy height within 4 km. Our findings add to the understanding of how wild turkeys are returning and using novel urban ecosystems and can inform future management needs, contribute to conservation initiatives, and help reduce negative human–wildlife interactions.

  PublisherOA PDFDOI

• Dietary kinetics of a PFAS mixture in the American toad (<i>Anaxyrus americanus</i>): laboratory insights into trophic transfer of PFAS

  Environmental Toxicology and Chemistry · 2025-07-16 · 1 citations

  article

  Per- and polyfluoroalkyl substances (PFAS) are ubiquitous in environmental media and are a concern for food web-driven exposure to ecological receptors. Terrestrial life stage amphibians concurrently represent taxa that have high potential for exposure but are generally data-poor in comparison to their aquatic life stages. Adult American toads (Anaxyrus americanus) likely have high dermal exposure to soil and eat terrestrial organisms that are likely to accumulate chemicals from soil. To better understand the relationship between dietary PFAS and toads in a trophic transfer context, toads were fed earthworms (Eisenia andrei) exposed to PFAS-spiked soil for 28 days and then were fed clean earthworms for 28 days-a 28-day uptake phase and 28-day elimination phase. Toad blood, liver, and remaining tissues were sampled weekly. Concentrations of PFAS were quantified in soil, earthworm diet, and toad tissues. Toxicokinetics of PFAS in toad livers, remainder, and estimated whole animal were evaluated using the methods of Organisation for Economic Co-operation and Development Test Guideline #305, a nonlinear regression approach, and a physiologically-based method. Definitive models were selected via a leave-one-out cross validation method and model parameters were used to determine kinetic trophic transfer coefficients (TTCs). Our TTC approach indicates perfluorooctane sulfonate, perfluoroundecanoic acid, and perfluorodecanoate are likely to magnify and 8:2 fluorotelomer sulfonate and perfluoroheptane sulfonic acid are likely to transfer or dilute in the worm-toad transition. Most PFAS have similar uptake rates, but elimination rates are clustered, suggesting that kinetics are driven by elimination mechanisms. These laboratory data use field-representative exposure approaches and provide inference about internal kinetics of individual PFAS as well as the potential for trophic transfer from soil invertebrates to terrestrial life stage amphibian predators.

  PublisherDOI

• SNAPSHOT USA 2019–2023: The First Five Years of Data From a Coordinated Camera Trap Survey of the United States

  Zenodo (CERN European Organization for Nuclear Research) · 2025-01-01

  articleOpen access

  (Uploaded by Plazi for the Bat Literature Project) Motivation: SNAPSHOT USA is an annual, multicontributor camera trap survey of mammals across the United States. The growing SNAPSHOT USA dataset is intended for tracking the spatial and temporal responses of mammal populations to changes in land use, land cover and climate. These data will be useful for exploring the drivers of spatial and temporal changes in relative abundance and distribution, as well as the impacts of species interactions on daily activity patterns.

  PublisherDOI

• Navigating the urban landscape: Integrating animal movement ecology with the One Health framework to better understand urban ecosystems

  BioScience · 2025-06-30

  articleSenior author

  Abstract The expansion of urban areas and anthropogenic activities have intensified human–wildlife interactions, increasing zoonotic disease emergence and transmission. Understanding factors influencing urban wildlife movement and their interactions with humans is critical for addressing disease transmission. We examine factors driving zoonotic risks in urban ecosystems, emphasizing the human–wildlife interactions, and suggest their integration into a One Health framework. Urban environments facilitate contact with wildlife reservoirs of zoonotic pathogens such as rabies, Lyme disease, and SARS-CoV-2. Factors such as green spaces, altered wildlife behavior, and human mobility amplify disease spillover risks. We emphasize applying movement ecology concepts, particularly for understanding how animals and humans navigate and use urban spaces to identify hotspots interaction and inform management strategies. Despite advancements, challenges such as data standardization and limited interdisciplinary collaboration persist. We advocate for an integrative approach combining animal movement ecology, human mobility, and public health to foster coexistence and safeguard human health.

  PublisherDOI

• Evaluation of SARS-CoV-2 antibody detection methods for wild Cervidae

  Preventive Veterinary Medicine · 2025-03-30 · 4 citations

  articleOpen access

  Wildlife surveillance programs often use serological data to monitor exposure to pathogens. Diagnostic sensitivity and specificity of a serological assay quantify the true positive and negative rates of the diagnostic assay, respectively. However, an assay's accuracy can be affected by wild animals' pathogen exposure history and quality of the sample collected, requiring separate estimates of an assay's detection ability for wild-sampled animals where an animal's true disease status is unknown (referred to hereafter as sampling sensitivity and specificity). We assessed the sampling sensitivity and specificity of a Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) surrogate virus neutralization test (sVNT) and conventional virus neutralization tests (cVNT) to detect antibodies for ancestral and Omicron B.1.1.529 variants of SARS-CoV-2 in wild white-tailed deer (Odocoileus virginianus) and mule deer (Odocoileus hemionus). We studied the influence of sample collection method using paired blood samples collected in serum separator tubes and on Nobuto strips from the same animal. Mean estimates of sampling sensitivity and specificity ranged from 0.21-0.95 and 0.94-1.00, respectively, varying by sample collection method, host species, and SARS-CoV-2 variant targeted by the assay. Broadly, sampling sensitivity was estimated to be higher for 1) sera collected in tubes, 2) detecting pre-Omicron SARS-CoV-2 variants, and 3) sVNT relative to cVNT assays. Sampling specificity tended to be high for all tests. We augmented our study with SARS-CoV-2 spike protein sequences derived from sampling locations and times coincident with white-tailed deer captures, finding common amino acid mutations relative to the sVNT Omicron antigen variant. The mutations may indicate that the SARS-CoV-2 variants circulating in cervids from 2021 through 2024 may be better adapted to cervid hosts and more closely related to variants that circulated in humans prior to Omicron variants. We conclude our study with an inter-test comparison of sVNT results, revealing that 40 % inhibition is an optimal threshold for test positivity when testing deer sera for responses to Omicron variant B.1.1.529, compared to the 30 % inhibition recommended for ancestral variants.

  PublisherDOI

• Large-scale experimental assessment of coyote behavior across urban and rural landscapes

  Scientific Reports · 2025-12-17

  articleOpen access

  Carnivores must navigate the complexities of human modifications to their environment. Natural resources and biodiversity decline in urban areas, while people in rural areas often pose greater direct risk through actions such as hunting. To evaluate if carnivore populations adapt their behavior to local risks in rural and urban environments, we compared behavioral responses to novel objects in coyotes (Canis latrans). We placed an attractant at arrays of 30 camera-trap stations at 16 pairs of urban and rural field sites across the USA, with a novel object placed at half of the stations. Coyotes exhibited more cautious behavior and remained farther from the attractant at all sites with the novel object; however, urban coyotes got closer to the attractant than rural coyotes. There were few behavioral differences between urban and rural coyotes and none between eastern and western coyotes. Coyotes across the USA exhibit neophobic behavior but urban coyotes, especially western coyotes, are willing to take more risk (i.e., be closer to the attractant). The consistency in most metrics of coyote behavior suggest that solutions developed in one area could be universally useful. This study also demonstrates the effectiveness of a large, collaborative approach to studying broad-scale patterns in behavioral traits.

  PublisherOA PDFDOI

• SNAPSHOT USA 2019–2023: The First Five Years of Data From a Coordinated Camera Trap Survey of the United States

  Zenodo (CERN European Organization for Nuclear Research) · 2025-01-01

  articleOpen access

  (Uploaded by Plazi for the Bat Literature Project) Motivation: SNAPSHOT USA is an annual, multicontributor camera trap survey of mammals across the United States. The growing SNAPSHOT USA dataset is intended for tracking the spatial and temporal responses of mammal populations to changes in land use, land cover and climate. These data will be useful for exploring the drivers of spatial and temporal changes in relative abundance and distribution, as well as the impacts of species interactions on daily activity patterns.

  PublisherDOI

• Expanding National‐Scale Wildlife Disease Surveillance Systems With Research Networks

  Ecology and Evolution · 2025-06-01 · 5 citations

  articleOpen access

  Efficient learning about disease dynamics in free-ranging wildlife systems can benefit from active surveillance that is standardized across different ecological contexts. For example, active surveillance that targets specific individuals and populations with standardized sampling across ecological contexts (landscape-scale targeted surveillance) is important for developing a mechanistic understanding of disease emergence, which is the foundation for improving risk assessment of zoonotic or wildlife-livestock disease outbreaks and predicting hotspots of disease emergence. However, landscape-scale targeted surveillance systems are rare and challenging to implement. Increasing experience and infrastructure for landscape-scale targeted surveillance will improve readiness for rapid deployment of this type of surveillance in response to new disease emergence events. Here, we describe our experience developing and rapidly deploying a landscape-scale targeted surveillance system for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in two free-ranging deer species across their ranges in the United States. Our surveillance system was designed to collect data across individual, population, and landscape scales for future analyses aimed at understanding mechanisms and risk factors of SARS-CoV-2 transmission, evolution, and persistence. Our approach leveraged partnerships between state and federal public service sectors and academic researchers in a landscape-scale targeted surveillance research network. Methods describe our approach to developing the surveillance network and sampling design. Results report challenges with implementing our intended sampling design, specifically how the design was adapted as different challenges arose and summarize the sampling design that has been implemented thus far. In the discussion, we describe strategies that were important for the successful deployment of landscape-scale targeted surveillance, development and operation of the research network, construction of similar networks in the future, and analytical approaches for the data based on the sampling design.

  PublisherOA PDFDOI

Frequent coauthors

• Mason Fidino

  Lincoln Park Zoo

  18 shared

• Seth B. Magle

  Lincoln Park Zoo

  17 shared

• Elizabeth W. Lehrer

  Lincoln Park Zoo

  14 shared

• William J. McShea

  National Zoological Park

  10 shared

• Daniel J. Herrera

  George Mason University

  10 shared

• Liba Pejchar

  Colorado State University

  10 shared

• Adam A. Ahlers

  Kansas State University

  9 shared

• Kelly Simon

  Texas Parks and Wildlife Department

  8 shared

Awards & honors

• Excellence in Extension Award
• Excellence in Instruction Award
• Excellence in Research Award