Unit Leader - Virginia Cooperative Fish and Wildlife Research Unit
Mark leads research on endangered, threatened, and species of greatest conservation need as well as high-profile game species in the eastern U.S.
Mark and his graduate students lead research on bat habitat use, distribution, population ecology, response to land management and post-White-nose Syndrome sampling methods (endangered Indiana bat, endangered gray bat and threatened northern long-eared bat throughout the mid-Atlantic and Northeast). His team also studies the Appalachian northern flying squirrel, elk, white-tailed deer, spruce-fir ecology, energy and wildlife, and prescribed burning (fire).Mark and his graduate students lead research on bat habitat use, distribution, population ecology, response to land management and post-White-nose Syndrome sampling methods (endangered Indiana bat, endangered gray bat and threatened northern long-eared bat throughout the mid-Atlantic and Northeast). His team also studies the Appalachian northern flying squirrel, elk, white-tailed deer, spruce-fir ecology, energy and wildlife, and prescribed burning (fire).
Professional Experience
Pathogen-mediated competition explains remnant bat community responses to white-nose syndrome.
Analytical assessments in support of the U.S. Fish and Wildlife Service 3-bat species status assessment.
Monitoring and modeling tree bat occurrence using acoustics on structures off the Mid-Atlantic coast—implications for offshore wind development.
White-nose syndrome and environmental correlates to landscape-scale bat presence.
Bat activity patterns relative to temporal and weather in a temperate coastal environment.
Demography of the Appalachian spotted skunk.
Predicted spatial distribution of the Eastern spotted skunk in Virginia using detection and non-detection records.
Forecasting the distribution of a bat reveals future response to climate change and habitat.
Northern long-eared bat day-roost loss in the Central Appalachian Mountains following prescribed burning (fire).
Fire, land cover and temperature drivers of bat activity in the winter.
White-nose syndrome-related changes to Mid-Atlantic bat in urban and rural areas.
Spatial habitat shared by behavior of Northern flying squirrels. Spatial (habitat shared by several species).
Education and Certifications
PhD Forest Resources, University of Georgia, 1994
MS Wildlife Ecology, Mississippi State University, 1989
BS Wildlife & Fisheries Science, University of Tennessee,1987
Certified Wildlife Biologist, The Wildlife Society, 1998
Abstracts and Presentations
An update on mid-Atlantic/Northeast Hub activities and estimates of species occupancy, detection and survey effort requirements with recommendations to support the North American Bat Monitoring Program from Maine. 2022 Northeast Bat Working Group. Manchester, New Hampshire. Jan. 12-14, 2022.
Broad-scale geographic and temporal assessment of northern long-eared bat maternity colony-landscape association. 2022 Northeast Bat Working Group, Manchester, New Hampshire, January 12-14, 2022
Post-white nose syndrome population structure of northern long-eared bats in the eastern United States. 2022 Northeast Bat Working Group, Manchester, New Hampshire, January 12-14, 2022.
An update on acoustic sampling level of effort for the Indiana, northern long-eared, little brown and tri-colored bats. 2022 Northeast Bat Working Group. Manchester, New Hampshire, Jan. 12-14, 2022.
Fall migration, oceanic movement and site residency patterns of migratory bats on the mid-Atlantic Coast with emphasis on eastern red bats.
Advancing a framework in increase community support for utility-scale solar photovoltaics. Solar Power and Wildlife/Natural Resources Symposium, Dec 1-3, 2021.
Predation and disease limit population recovery of a cryptic small carnivore, the Appalachian spotted skunk. 28th Annual Meeting of the Wildlife Society, Nov. 1-5, 2021.
Science and Products
Point Location of Myotis septentrionalis Echolocation Passes in Eastern North Carolina and Virginia
These data are the location and date of collection of endangered northern long-eared bat Myotis septentrionalis echolocation passes when the automated bat identification software assessed species presence at a maximum likelihood estimator p-value of less than or equal to 0.05 consistent with the U.S. Fish and Wildlife Service monitoring guideline standards.
Mid-Atlantic Coast, Lasiurus borealis Movement and Migration
The data in the CSV file named RSF is a detailed dataset used to run the models testing relationships between movement behavior and atmospheric conditions. This dataset includes: detection date and rounded hour, status (0 or 1) showing if over-water movement occurring within nine hours was detected, number of hours since sunset, site ID of area weather station, Motus tag ID, wind speed , Temperatu
Sample locations 2022 SARS-CoV-2 testing in little brown bats
The potential introduction of SARS-CoV-2, the virus responsible for the COVID-19 pandemic, into North American bat populations is of interest to wildlife managers due to recent declines of several species. Populations of little brown bats (Myotis lucifugus) have collapsed due to white-nose syndrome (WNS), a disease caused by the introduction and spread of the fungal pathogen Pseudogymnoascus destr
Bat Detector Type Comparison Data from Fort Knox, Kentucky
These data are night level totals of bat calls by species and phonic group recorded at Fort Knox, Kentucky during the summer of 2017. Data contain recordings from zero-crossing frequency division and full spectrum receiving units.
Acoustic Parameters Collected in an Anechoic Chamber
Synthetic bat call parameters recorded in an anecolic chamber using full spectrum receivers. Data were then converted to zero-crossing format to measure parameters such as minimum, average and maximum frequency, number of echoes and number of correctly identified files
Roost selection for Northern Long-eared Bats (Myotis septentrionalis) in Wisconsin
These data represent characteristics of trees used by Northern long-eared bats as roosts at three sites in Wisconsin, as well as characteristics of surrounding trees to compare characteristics of used versus available trees.
Activity patterns of cave-dwelling bat species during pre-hibernation swarming and post-hibernation emergence in the central Appalachians
Bat activity around known hibernacula in Virginia and West Virginia portion of the central Appalachians during the fall swarm and spring emergence, 2015-2017
Filter Total Items: 56
Statistical assessment on determining local presence of rare bat species
Surveying cryptic, sparsely distributed taxa using autonomous recording units, although cost-effective, provides imperfect knowledge about species presence. Summertime bat acoustic surveys in North America exemplify the challenges with characterizing sources of uncertainty: observation error, inability to census populations, and natural stochastic variation. Statistical uncertainty, if not conside
Authors
Kathryn M. Irvine, Katharine M. Banner, Christian Stratton, W. Mark Ford, Brian Reichert
Effects of environmental clutter on synthesized chiropteran echolocation signals in an anechoic chamber
Ultrasonic bat detectors are useful for research and monitoring purposes to assess occupancy and relative activity of bat communities. Environmental “clutter” such as tree boles and foliage can affect the recording quality and identification of bat echolocation calls collected using ultrasonic detectors. It can also affect the transmission of calls and recognition by bats when using acoustic lure
Authors
Samuel R. Freeze, Masoud Shirazi, Nicole Abaid, W. Mark Ford, Alexander Silvis, Dawn Hakkenberg
Context dependency of disease-mediated competitive release in bat assemblages following white-nose syndrome
White-nose syndrome (WNS) has caused dramatic declines of several cave-hibernating bat species in North America since 2006, which has increased the activity of non-susceptible species in some geographic areas or during times of night formerly occupied by susceptible species—indicative of disease-mediated competitive release (DMCR). Yet, this pattern has not been evaluated across multiple bat assem
Authors
Sara Bombaci, Robin E. Russell, Michael J. St. Germain, Christopher A. Dobony, W. Mark Ford, Susan Loeb, David S. Jachowski
Monitoring and modeling tree bat (Genera: Lasiurus, Lasionycteris) occurrence using acoustics on structures off the mid-Atlantic coast—Implications for offshore wind development
In eastern North America, “tree bats” (Genera: Lasiurus and Lasionycteris) are highly susceptible to collisions with wind energy turbines and are known to fly offshore during migration. This raises concern about ongoing expansion of offshore wind-energy development off the Atlantic Coast. Season, atmospheric conditions, and site-level characteristics such as local habitat (e.g., forest coverage) h
Authors
Michael C. True, Richard J. Reynolds, W. Mark Ford
White-nose Syndrome and environmental correlates to landscape-scale bat presence
Over the past 13 years, White-nose Syndrome (WNS) has caused North American bat population declines and shifted community structure towards species less or unaffected by the disease. Mist-netting, acoustic surveys, and cave count data have been used to document changes in bat presence and activity through site-specific, pre- and post-WNS studies. Management and survey guidance often must be applie
Authors
Elaine L. Barr, Alexander Silvis, Mike P. Armstrong, W. Mark Ford
Demography of the Appalachian Spotted Skunk (Spilogale putorius putorius)
Spilogale putorius (Eastern Spotted Skunk) is a small, secretive carnivore that has substantially declined throughout the eastern United States since the mid-1900s. To better understand the current status of Eastern Spotted Skunks, we studied survival and reproduction of the S. p. putorius (Appalachian Spotted Skunk) subspecies across 4 states in the central and southern Appalachian Mountains from
Authors
Andrew R. Butler, Andrew J. Edelman, Robin Y. Y. Eng, Stephen N. Harris, Colleen Olfenbuttel, Emily D. Thorne, W. Mark Ford, David S. Jachowski
Predicted spatial distribution of the Eastern Spotted Skunk (Spilogale putorius) in Virginia using detection and non-detection records
The geographic distribution of a species is a fundamental component in understanding its ecology and is necessary for forming effective conservation plans. For rare and elusive species of conservation concern, accurate maps of predicted occurrence are particularly problematic and often highly subjective. Spilogale putorius (Eastern Spotted Skunk) populations have experienced large declines since t
Authors
Emily D. Thorne, W. Mark Ford
Forecasting the distribution of a range-expanding bat reveals future response to climate change and habitat
Many terrestrial vertebrate species are exhibiting geographic distribution changes including poleward range limit shifts in response to increases in regional temperature. Bats are a highly mobile taxa capable of rapid responses to changes in abiotic or biotic conditions. In North America, recent extralimital records of the non-hibernating Lasiurus seminolus (Seminole bat) have been attributed to c
Authors
Michael C. True, Roger W. Perry, W. Mark Ford
Fire, land cover, and temperature drivers of bat activity in winter
BackgroundUnderstanding the effects of disturbance events, land cover, and weather on wildlife activity is fundamental to wildlife management. Currently, in North America, bats are of high conservation concern due to white-nose syndrome and wind-energy development impact, but the role of fire as a potential additional stressor has received less focus. Although limited, the vast majority of researc
Authors
Marcelo H. Jorge, Sara E. Sweeten, Michael C. True, Samuel R. Freeze, Michael J. Cherry, Elina P. Garrison, W. Mark Ford
Post-white-nose syndrome passive acoustic sampling effort for determining bat species occupancy within the mid-Atlantic region
We assessed the sampling effort requirements for detecting the presence of extant bat species following the impact of white-nose syndrome in the mid-Atlantic region of the United States. We acoustically sampled 27,796 nights across 846 sites between 15 May and 15 August 2016–2018 within the District of Columbia, Maryland, Pennsylvania, Virginia, and West Virginia. We developed simulations to deter
Authors
Sabrina M. Deeley, Nicholas J. Kalen, Samuel R. Freeze, Elaine L. Barr, W. Mark Ford
White-nose syndrome-related changes to Mid-Atlantic bat communities across an urban-to-rural gradient
BackgroundWhite-nose Syndrome (WNS) has reduced the abundance of many bat species within the United States’ Mid-Atlantic region. To determine changes within the National Park Service National Capital Region (NCR) bat communities, we surveyed the area with mist netting and active acoustic sampling (2016–2018) and compared findings to pre-WNS (2003–2004) data.ResultsThe results indicated the continu
Authors
Sabrina M. Deeley, Joshua B. Johnson, W. Mark Ford, J. Edward Gates
Developing species-age cohorts from forest inventory and analysis data to parameterize a forest landscape model
Simulating long-term, landscape level changes in forest composition requires estimates of stand age to initialize succession models. Detailed stand ages are rarely available, and even general information on stand history often is lacking. We used data from USDA Forest Service Forest Inventory and Analysis (FIA) database to estimate broad age classes for a forested landscape to simulate changes in
Authors
Richard H. Odom, W. Mark Ford
Science and Products
- Data
Point Location of Myotis septentrionalis Echolocation Passes in Eastern North Carolina and Virginia
These data are the location and date of collection of endangered northern long-eared bat Myotis septentrionalis echolocation passes when the automated bat identification software assessed species presence at a maximum likelihood estimator p-value of less than or equal to 0.05 consistent with the U.S. Fish and Wildlife Service monitoring guideline standards.Mid-Atlantic Coast, Lasiurus borealis Movement and Migration
The data in the CSV file named RSF is a detailed dataset used to run the models testing relationships between movement behavior and atmospheric conditions. This dataset includes: detection date and rounded hour, status (0 or 1) showing if over-water movement occurring within nine hours was detected, number of hours since sunset, site ID of area weather station, Motus tag ID, wind speed , TemperatuSample locations 2022 SARS-CoV-2 testing in little brown bats
The potential introduction of SARS-CoV-2, the virus responsible for the COVID-19 pandemic, into North American bat populations is of interest to wildlife managers due to recent declines of several species. Populations of little brown bats (Myotis lucifugus) have collapsed due to white-nose syndrome (WNS), a disease caused by the introduction and spread of the fungal pathogen Pseudogymnoascus destrBat Detector Type Comparison Data from Fort Knox, Kentucky
These data are night level totals of bat calls by species and phonic group recorded at Fort Knox, Kentucky during the summer of 2017. Data contain recordings from zero-crossing frequency division and full spectrum receiving units.Acoustic Parameters Collected in an Anechoic Chamber
Synthetic bat call parameters recorded in an anecolic chamber using full spectrum receivers. Data were then converted to zero-crossing format to measure parameters such as minimum, average and maximum frequency, number of echoes and number of correctly identified filesRoost selection for Northern Long-eared Bats (Myotis septentrionalis) in Wisconsin
These data represent characteristics of trees used by Northern long-eared bats as roosts at three sites in Wisconsin, as well as characteristics of surrounding trees to compare characteristics of used versus available trees.Activity patterns of cave-dwelling bat species during pre-hibernation swarming and post-hibernation emergence in the central Appalachians
Bat activity around known hibernacula in Virginia and West Virginia portion of the central Appalachians during the fall swarm and spring emergence, 2015-2017 - Publications
Filter Total Items: 56
Statistical assessment on determining local presence of rare bat species
Surveying cryptic, sparsely distributed taxa using autonomous recording units, although cost-effective, provides imperfect knowledge about species presence. Summertime bat acoustic surveys in North America exemplify the challenges with characterizing sources of uncertainty: observation error, inability to census populations, and natural stochastic variation. Statistical uncertainty, if not consideAuthorsKathryn M. Irvine, Katharine M. Banner, Christian Stratton, W. Mark Ford, Brian ReichertEffects of environmental clutter on synthesized chiropteran echolocation signals in an anechoic chamber
Ultrasonic bat detectors are useful for research and monitoring purposes to assess occupancy and relative activity of bat communities. Environmental “clutter” such as tree boles and foliage can affect the recording quality and identification of bat echolocation calls collected using ultrasonic detectors. It can also affect the transmission of calls and recognition by bats when using acoustic lureAuthorsSamuel R. Freeze, Masoud Shirazi, Nicole Abaid, W. Mark Ford, Alexander Silvis, Dawn HakkenbergContext dependency of disease-mediated competitive release in bat assemblages following white-nose syndrome
White-nose syndrome (WNS) has caused dramatic declines of several cave-hibernating bat species in North America since 2006, which has increased the activity of non-susceptible species in some geographic areas or during times of night formerly occupied by susceptible species—indicative of disease-mediated competitive release (DMCR). Yet, this pattern has not been evaluated across multiple bat assemAuthorsSara Bombaci, Robin E. Russell, Michael J. St. Germain, Christopher A. Dobony, W. Mark Ford, Susan Loeb, David S. JachowskiMonitoring and modeling tree bat (Genera: Lasiurus, Lasionycteris) occurrence using acoustics on structures off the mid-Atlantic coast—Implications for offshore wind development
In eastern North America, “tree bats” (Genera: Lasiurus and Lasionycteris) are highly susceptible to collisions with wind energy turbines and are known to fly offshore during migration. This raises concern about ongoing expansion of offshore wind-energy development off the Atlantic Coast. Season, atmospheric conditions, and site-level characteristics such as local habitat (e.g., forest coverage) hAuthorsMichael C. True, Richard J. Reynolds, W. Mark FordWhite-nose Syndrome and environmental correlates to landscape-scale bat presence
Over the past 13 years, White-nose Syndrome (WNS) has caused North American bat population declines and shifted community structure towards species less or unaffected by the disease. Mist-netting, acoustic surveys, and cave count data have been used to document changes in bat presence and activity through site-specific, pre- and post-WNS studies. Management and survey guidance often must be applieAuthorsElaine L. Barr, Alexander Silvis, Mike P. Armstrong, W. Mark FordDemography of the Appalachian Spotted Skunk (Spilogale putorius putorius)
Spilogale putorius (Eastern Spotted Skunk) is a small, secretive carnivore that has substantially declined throughout the eastern United States since the mid-1900s. To better understand the current status of Eastern Spotted Skunks, we studied survival and reproduction of the S. p. putorius (Appalachian Spotted Skunk) subspecies across 4 states in the central and southern Appalachian Mountains fromAuthorsAndrew R. Butler, Andrew J. Edelman, Robin Y. Y. Eng, Stephen N. Harris, Colleen Olfenbuttel, Emily D. Thorne, W. Mark Ford, David S. JachowskiPredicted spatial distribution of the Eastern Spotted Skunk (Spilogale putorius) in Virginia using detection and non-detection records
The geographic distribution of a species is a fundamental component in understanding its ecology and is necessary for forming effective conservation plans. For rare and elusive species of conservation concern, accurate maps of predicted occurrence are particularly problematic and often highly subjective. Spilogale putorius (Eastern Spotted Skunk) populations have experienced large declines since tAuthorsEmily D. Thorne, W. Mark FordForecasting the distribution of a range-expanding bat reveals future response to climate change and habitat
Many terrestrial vertebrate species are exhibiting geographic distribution changes including poleward range limit shifts in response to increases in regional temperature. Bats are a highly mobile taxa capable of rapid responses to changes in abiotic or biotic conditions. In North America, recent extralimital records of the non-hibernating Lasiurus seminolus (Seminole bat) have been attributed to cAuthorsMichael C. True, Roger W. Perry, W. Mark FordFire, land cover, and temperature drivers of bat activity in winter
BackgroundUnderstanding the effects of disturbance events, land cover, and weather on wildlife activity is fundamental to wildlife management. Currently, in North America, bats are of high conservation concern due to white-nose syndrome and wind-energy development impact, but the role of fire as a potential additional stressor has received less focus. Although limited, the vast majority of researcAuthorsMarcelo H. Jorge, Sara E. Sweeten, Michael C. True, Samuel R. Freeze, Michael J. Cherry, Elina P. Garrison, W. Mark FordPost-white-nose syndrome passive acoustic sampling effort for determining bat species occupancy within the mid-Atlantic region
We assessed the sampling effort requirements for detecting the presence of extant bat species following the impact of white-nose syndrome in the mid-Atlantic region of the United States. We acoustically sampled 27,796 nights across 846 sites between 15 May and 15 August 2016–2018 within the District of Columbia, Maryland, Pennsylvania, Virginia, and West Virginia. We developed simulations to deterAuthorsSabrina M. Deeley, Nicholas J. Kalen, Samuel R. Freeze, Elaine L. Barr, W. Mark FordWhite-nose syndrome-related changes to Mid-Atlantic bat communities across an urban-to-rural gradient
BackgroundWhite-nose Syndrome (WNS) has reduced the abundance of many bat species within the United States’ Mid-Atlantic region. To determine changes within the National Park Service National Capital Region (NCR) bat communities, we surveyed the area with mist netting and active acoustic sampling (2016–2018) and compared findings to pre-WNS (2003–2004) data.ResultsThe results indicated the continuAuthorsSabrina M. Deeley, Joshua B. Johnson, W. Mark Ford, J. Edward GatesDeveloping species-age cohorts from forest inventory and analysis data to parameterize a forest landscape model
Simulating long-term, landscape level changes in forest composition requires estimates of stand age to initialize succession models. Detailed stand ages are rarely available, and even general information on stand history often is lacking. We used data from USDA Forest Service Forest Inventory and Analysis (FIA) database to estimate broad age classes for a forested landscape to simulate changes inAuthorsRichard H. Odom, W. Mark Ford - News