Todd Esque
Biography
Dr. Todd Esque's research interests are in disturbance ecology with emphasis in areas of community ecology, herpetology, invasive species and fire, habitat restoration, and conservation biology.
Dr. Esque's work focuses on understanding how organisms, habitats, and ecosystem processes respond to environmental change, how organisms interact to effect change, and how human-induced changes compare to the natural range of variation in arid systems. Recent work focuses on the synthesis of these experiments into regional analyses of habitat suitability and connectivity in response to global change and other anthropogenic disturbances for use by natural resource managers.
Representative studies include: projects to determine how desert tortoises, Mojave ground squirrels, golden eagles, long-lived plants, and biodiversity will respond to climate change and energy development in a rapidly changing landscape; vegetation change from fires across a 30-year chronosequence in Sonoran desert tortoise habitat; identifying habitat and health relationships for the desert tortoise, and developing a vegetation restoration program for the Mojave Desert.
Dr. Esque's projects are collaborative and interdisciplinary in nature and he is active in academic research as well as applied problems for public entities in the Department of Interior (Bureau of Land Management, National Park Service, U.S. Fish and Wildlife Service), Department of Defense, State and local governments, and private entities.
RESEARCH INTERESTS
- Arid Systems
- Conservation Biology
- Disturbance and Restoration Ecology
- Demographic and Habitat Modeling
- Community Ecology
- Invasive Species and Wildfire
- Energy Development
EDUCATION
- 2004 Ph.D. Ecology Evolution, and Conservation Biology, University of Nevada, Reno
- 1994 M.S. Zoology, Colorado State University
- 1982 B.A. Biology, Prescott College, Arizona
PROFESSIONAL AND HONORARY SOCIETIES AND SCIENCE ADVISORY COMMITTEES
- Desert Renewable Energy Conservation Plan – Science Advisory Committee 2012
- BLM – Rapid Ecoregional Assessments – lead USGS science reviewer for the Mojave and Sonoran Ecoregions 2013
PROFESSIONAL EXPERIENCE
- Research Ecologist, USGS, Western Ecological Research Center, 1997-Present
- Station Leader, USGS, St. George Field Station, 1994-1997
- Research Ecologist, USGS, Mid-continent Ecological Science Center, 1996- 1997
- Research Ecologist, National Biological Service (Survey), Mid-continent Ecological Science Center, 1993 - 1996
- Ecologist, Bureau of Land Management, Dixie Resource Area, Utah, 1993 - 1993
- Research Technician, Fish and Wildlife Service, Region 8, Research, Ft. Collins, CO 1986-1993
Science and Products
WERC Fire Science
WERC scientists are defining the past, present, and future of wildfires for wildlife and human communities. Explore this webpage to learn about specific, ongoing projects across California and parts of Nevada.
Aridlands Disturbances and Restoration Ecology
Desert landscapes are rapidly changing due to increases in invasive plant species, frequency of wildfires, urban and energy development, recreational use, military training, and climate variation. Dr. Todd Esque, USGS researchers, and collaborators are working together to investigate these changes and provide managers with key information that can be used to manage natural resources more...
Desert Tortoise Ecology, Health, Habitat, and Conservation Biology
The desert tortoise is listed as “threatened” under the Endangered Species Act. USGS WERC scientists, along with project partners have been conducting long-term analyses on how changes in the southwestern deserts of the United States can affect desert tortoise populations. Dr. Todd Esque and his team are investigating how habitat disturbances and restoration projects influence tortoise...
Southwestern Desert Ecology of At-risk Species and their Habitats
The southwestern desert region is home to many sensitive species. Species are at-risk due to past, present, and future changes to the landscape. WERC’s Dr. Todd Esque, field researchers, and collaborators are using models, monitoring plans, and decision-support tools to provide land managers with the resources they need to answer questions about how environmental change influences plants,...
Ecology and Conservation of Golden Eagles in the Mojave Desert
Dr. Kathleen Longshore, in collaboration with Dr. Todd Esque, provides information to project the possible conflict between losses of habitat for foraging involved in the proposed development of alternative energy installations in the Mojave Desert and help develop advanced conservation efforts for the golden eagle. Information from this project will also inform California’s Desert Renewable...
Henderson Field Station
The Henderson Field Station supports research scientists leading projects in desert ecosystem restoration, genetics of iconic trees of the Mojave Desert, predator-prey studies on protected lands, and more. Select the next tab for a comprehensive summary of studies at this site.
Local ecological niche models, genotype associations and environmental data for desert tortoises
These data include environmental covariates used to develop species distribution models for Gopherus agassizii and Gopherus morafkai, along with PCA-reduced environmental covariates used to explore local species-environment relationships within a subregion of the ectone between the two species. We also provide the genotype association used to test the mapped clusters of multiscale...
Climate Distance Mapper - web application
Climate Distance Mapper is a spatial decision-support tool designed to help land managers match seed sources with restoration sites. Plant populations are commonly adapted to local climate gradients and frequently exhibit a home-site advantage. For this reason, climate information may serve as a proxy for local adaptation in restoration designs. Climate Distance Mapper allows users to rank the...
Principal components of climate variation in the Desert Southwest for the time periods 1980-2010, 2040-2070 (RCP8.5) and (RCP4.5)
Five principal components are used to represent the climate variation in an original set of 12 climate variables reflecting precipitation and temperature gradients. The dataset provides coverage for four regions (the Sonoran Desert, Mojave Desert, Colorado Plateau, and Southern Great Basin) and two time periods: current climate (defined as the 1980-2010 normal period) and future c
Spatial predictions of habitat suitability for present-day (1950 – 2000 yr) and mid-Holocene (8.3 ka – 4.2 ka) time intervals
This dataset provides spatial predictions of habitat suitability for current (1950 – 2000 yr) and mid-Holocene (8.3 ka – 4.2 ka) intervals using hindcasting, and three separate paleo-distributions calibrated on the packrat midden archive: those without bias correction (naïve), those created with a standard method (standard), and those created with a novel...
Estimates of pathogen exposure predict varying transmission likelihood: Host contact and shedding patterns may clarify disease dynamics in desert tortoises Gopherus agassizii
These datasets (S2-S3) document the transmission of a bacterial pathogen (Mycoplasma agassizii) between desert tortoises (Gopherus agassizii) experimentally introduced in captivity and were used to create and compare models predicting transmission probability given data on the hosts and their interactions. Dataset S2 includes variables describing the individual tortoises interacting%2
Golden Eagle food habits in the Mojave Desert: Regional information for a changing landscape
Expansion of renewable energy development is rapidly transforming the Mojave Desert landscape and has the potential to impact Golden Eagles through loss of foraging habitat and reduced prey base. Regional information on Golden Eagle food habits is limited and little is known of how dietary variability influences eagle productivity. We examined diet using motion activated trail cameras and...
Integrating telemetry data at several scales with spatial capture–recapture to improve density estimates
Accurate population estimates are essential for monitoring and managing wildlife populations. Mark–recapture sampling methods have regularly been used to estimate population parameters for rare and cryptic species, including the federally listed Mojave desert tortoise (Gopherus agassizii); however, the methods employed are often plagued by...
Mitchell, Corey I; Shoemaker, Kevin T.; Esque, Todd C.; Vandergast, A. G.; Hromada, Steven J.; Dutcher, Kirsten E.; Heaton, Jill S.; Nussear, Kenneth E. Borreliosis transmission from ticks to humans associated with desert tortoise burrows: Examples of tick-borne relapsing fever in the Mojave Desert
Ticks transmit pathogens and parasitize wildlife in turn causing zoonotic diseases in many ecosystems. Argasid ticks, such as Ornithodoros spp., harbor and transmit Borrelia spp., resulting in tick-borne relapsing fever (TBRF) in people. In the western United States, TBRF is typically associated with the bite of an infected...
Bechtel, Molly J; Drake, K. Kristina; Esque, Todd C.; Nieto, Nathan C; Foster, Jeffrey T.; Teglas, Mike B Linking behavioral states to landscape features for improved conservation management
A central theme for conservation is understanding how animals differentially use, and are affected by change in, the landscapes they inhabit. However, it has been challenging to develop conservation schemes for habitat-specific behaviors.Here we use behavioral change point analysis to identify behavioral states of golden eagles (Aquila ...
Sur, Maitreyi; Woodbridge, Brian; Esque, Todd C.; Belthoff, Jim R; Bloom, Peter H.; Fisher, R. N.; Longshore, Kathleen; Nussear, Kenneth E.; Tracey, Jeff A.; Braham, Melissa A.; Katzner, Todd E. Assessment of disease risk associated with potential removal of anthropogenic barriers to Mojave desert tortoise (Gopherus agassizii) population connectivity
The Mojave Desert tortoise (Gopherus agassizii), federally listed as threatened, has suffered habitat loss and fragmentation due to human activities. Upper respiratory tract disease (URTD), a documented health threat to desert tortoises, has been detected at the Large-Scale Translocation Study Site (LSTS) in southwestern Nevada, US, a fenced...
Burgess, Tristan L.; Braun, Josephine; Witte, Carmel L; Lamberski, Nadine; Field. Kimberleigh J; Allison, Linda J.; Averill-Murray, Roy C.; Drake, K. Kristina; Nussear, Kenneth E.; Esque, Todd C.; Rideout, Bruce A Priority species lists to restore desert tortoise and pollinator habitats in Mojave Desert shrublands
Mojave Desert shrublands are home to unique plants and wildlife and are experiencing rapid habitat change due to unprecedented large-scale disturbances; yet, established practices to effectively restore disturbed landscapes are not well developed. A priority species list of native plant taxa was developed to guide seed collectors, commercial...
Esque, Todd C.; DeFalco, Lesley A.; Tyree, Gayle Loren; Drake, K. Kristina; Nussear, Kenneth E.; Wilson, Joseph S
Connectivity of Mojave Desert tortoise populations—Management implications for maintaining a viable recovery network
Executive SummaryThe historic distribution of Mojave desert tortoises (Gopherus agassizii) was relatively continuous across the range, and the importance of tortoise habitat outside of designated tortoise conservation areas (TCAs) to recovery has long been recognized for its contributions to supporting gene flow between TCAs and to minimizing...
Averill-Murray, Roy C.; Esque, Todd C.; Allison, Linda J.; Bassett, Scott; Carter, Sarah K.; Dutcher, Kirsten E.; Hromada, Steven J.; Shoemaker, Kevin T.; Nussear, Kenneth E. Comparing sample bias correction methods for species distribution modeling using virtual species
A key assumption in species distribution modeling (SDM) with presence‐background (PB) methods is that sampling of occurrence localities is unbiased and that any sampling bias is proportional to the background distribution of environmental covariates. This assumption is rarely met when SDM practitioners rely on federated museum records from natural...
Inman, Rich; Franklin, Janet; Esque, Todd C.; Nussear, Kenneth E. ‘Unscrambling’ the drivers of egg production in Agassiz’s desert tortoise: Climate and individual attributes predict reproductive output
ABSTRACT: The ‘bet hedging’ life history strategy of long-lived iteroparous species reduces short-term reproductive output to minimize the risk of reproductive failure over a lifetime. For desert-dwelling ectotherms living in variable and unpredictable environments, reproductive output is further influenced by precipitation and temperature via...
Mitchell, Corey I.; Friend, Derek A.; Phillips, Lauren T.; Hunter, Elizabeth A.; Lovich, Jeffrey E.; Agha, Mickey; Puffer, Shellie R.; Cummings, Kristy L.; Medica, Philip A.; Esque, Todd C.; Nussear, Kenneth E.; Shoemaker, Kevin T. Harnessing landscape genomics to identify future climate resilient genotypes in a desert annual
Local adaptation features critically in shaping species responses to changing environments, complicating efforts to revegetate degraded areas. Rapid climate change poses an additional challenge that could reduce fitness of even locally sourced seeds in restoration. Predictive restoration strategies that apply seeds with favourable adaptations to...
Shryock, Daniel F.; Washburn, Loraine K; DeFalco, Lesley A.; Esque, Todd C. Using movement to inform conservation corridor design for Mojave desert tortoise
BackgroundPreserving corridors for movement and gene flow among populations can assist in the recovery of threatened and endangered species. As human activity continues to fragment habitats, characterizing natural corridors is important in establishing and maintaining connectivity corridors within the anthropogenic development matrix. The Mojave...
Hromada, Steven J.; Esque, Todd C.; Vandergast, Amy G.; Dutcher, Kirsten E.; Mitchell, Corey I; Gray, Miranda E; Chang, Tony; Dickson, Brett G.; Nussear, Kenneth E. Quantifying development to inform management of Mojave and Sonoran desert tortoise habitat in the American southwest
Two tortoise species native to the American southwest have experienced significant habitat loss from development and are vulnerable to ongoing threats associated with continued development. Mojave desert tortoises Gopherus agassizii are listed as threatened under the US Endangered Species Act, and Sonoran desert tortoises G. morafkai are protected...
Carter, Sarah K.; Nussear, Kenneth E.; Esque, Todd C.; Leinwand, Ian IF; Masters, Elroy; Inman, Rich; Carr, Natasha B.; Allison, Linda J.
Using remotely sensed data to map Joshua Tree distributions at Naval Air Weapons Station China Lake, California, 2018
Species distribution models (SDMs) that are derived through inference have been used to provide important insights toward species distributions. Their inferences can be robust in relation to known presences, but SDMs have error rates that cannot be quantified with certainty. For large plant species with unique signatures and in sparsely vegetated...
Esque, Todd C.; Baird, Patrick E.; Chen, Felicia C.; Housman, David C.; Holton, Tom J.
Mojave Golden Eagles
This short video features incredible and graphic images and video of golden eagle prey. These birds are eating machines. USGS biologist-rock climbers install nest cameras to study the eating habits of golden eagles and their young in the Mojave Desert. This work goes towards creating a Prey Availability Habitat Model to better site green energy projects so that they will
The Heat is On: Desert Tortoises and Survival (Full video)
"The Heat is On: Desert Tortoises and Survival" is a thirty minute television program exploring the world of the Mojave Desert Tortoise. It highlights the USGS research program on the Desert Tortoise and the role of that research in managing desert environments to allow the species to recover and escape the threat of extinction. The program was originally released on
Linking Behavioral States to Landscape Features for Improved Conservation Management
Behavioral Change Point Analysis (BCPA) is a tool that analyzes changes in species’ movement and behavior.
12 Days of Conifer Bonus: Spiky Leaves Aren't Just For Conifers
Nothing like a baker’s dozen, right? As a bonus for 12 Days Of Conifers we have…. hey! That’s not a conifer!
In the Media: Desert Tortoise Researchers Featured by KUNC Public Radio
USGS scientists study threats to the Mojave desert tortoise
Not Just for Kissing: Mistletoe and Birds, Bees, and Other Beasts
Perhaps some of you have already experienced a sweet smooch or two under the holiday mistletoe, enjoying this fairly old kissing ritual for people. While figuring prominently in ancient lore, mistletoe is important in other vital ways: it provides essential food, cover and nesting sites for an amazing number of critters. In fact, some animals couldn’t even survive without mistletoe.
Not Just for Kissing: Mistletoe and Birds, Bees, and Other Beasts
Perhaps some of you have already experienced a sweet holiday smooch or two under the Christmas mistletoe, enjoying this fairly old kissing ritual for people.