Mark Haroldson
Mark Haroldson is a USGS Supervisory Wildlife Biologist for the Interagency Grizzly Bears Study Team and works out of the Northern Rocky Mountain Science Center, Bozeman, MT.
Research Interest
Mark has had a passion for bears since he began studying them as an undergraduate in 1976. He has worked in bear research and management in several western states ever since. Since 1984 he has worked in various capacities for the Interagency Grizzly Bear Study Team in the Greater Yellowstone Ecosystem. Current research is focused on mortality and population trend of grizzly bears in the Greater Yellowstone Ecosystem.
Education and Certifications
B.S. Wildlife Biology, 1979, University of Montana
Graduate level class work, 1982-88, University of Montana
Science and Products
Informing Management Options for grizzly bears in a Changing Greater Yellowstone Ecosystem
Project Overview The iconic grizzly bear of the Greater Yellowstone Ecosystem has exhibited a remarkable recovery in response to concerted conservation actions implemented since its listing as threatened under the Endangered Species Act in 1975. However, information regarding the potential effects and timing of climate change in conjunction with increasing human recreation and development will be
Interagency Grizzly Bear Study Team
The Interagency Grizzly Bear Study Team (IGBST) is an interdisciplinary group of scientists and biologists responsible for long-term monitoring and research efforts on grizzly bears in the Greater Yellowstone Ecosystem (GYE). The team was formed by the Department of the Interior (DOI) in 1973 as a direct result of controversy surrounding the closure of open pit garbage dumps within Yellowstone...
NOROCK Large Carnivore Research Program
NOROCK has substantial expertise in large carnivore research, primarily involving species listed as Threatened or Endangered. NOROCK’s Large Carnivore Research Program includes scientists from NOROCK’s Headquarters, West Glacier Field Station, and the Southern Appalachian Field Station. Studies are conducted in a wide variety of landscapes throughout the U.S., as well as international research...
Mortality, morphology, and water chemistry for 6PPD-quinone exposed coho embryos
Understanding evolutionary processes that drive population dynamics is critical in ecology. Measuring the performance-density relationship in long-lived mammalian species demands long-term data, limiting the ability to observe such mechanisms. We tested density-dependent (intrinsic) and density-independent (extrinsic) drivers of body composition of grizzly bears (Ursus arctos) in the Greater Yello
Body composition data of grizzly bears in the Greater Yellowstone Ecosystem 2000-2020
Understanding evolutionary processes that drive population dynamics is critical in ecology. Measuring the performance-density relationship in long-lived mammalian species demands long-term data, limiting the ability to observe such mechanisms. We tested density-dependent (intrinsic) and density-independent (extrinsic) drivers of body composition of grizzly bears (Ursus arctos) in the Greater Yello
Documented known and probable grizzly bear mortalities in the Greater Yellowstone Ecosystem, 2015-2023 (ver. 3.0 April 2024)
We evaluate mortalities for population segments within the DMA by deriving estimates of total mortality for independent-age (equal to or less than 2 years old) females and independent-age males, including estimates of unknown/unreported mortalities based on Cherry et al. (2002). We then determine the total annual mortality rate for these segments as a percent of their respective population estimat
Detection histories of grizzly bears in Grand Teton National Park, 2014-2015
This dataset contains detection histories of grizzly bears in areas of Grand Teton National Park that are open for elk harvest as part of the Elk Reduction Program. Sampling followed a robust design analysis with 6 primary sampling periods of 4 weekly secondary sampling periods each during 2014-2015. In both years, primary sampling periods were in July-August (no elk hunt), September-October (no e
Canine distemper virus antibody titer results for grizzly bears and wolves in the Greater Yellowstone Ecosystem 1984-2014
We investigated the dynamics of canine distemper virus (CDV) in grizzly bears (Ursus arctos) and wolves (Canis lupus) of the Greater Yellowstone Ecosystem using serological data collected from 1984 to 2014. 565 sera samples were obtained from 425 unique grizzly bears (134 females and 291 males) from 1984 to 2014 and 319 sera samples were obtained from 285 unique wolves (130 females and 155 males)
Potential movement paths for male grizzly bear (Ursus arctos) dispersal between the Northern Continental Divide and Greater Yellowstone Ecosystems, 2000-2015
For several decades, grizzly bear (Ursus arctos) populations in the Greater Yellowstone Ecosystem (GYE) and the Northern Continental Divide Ecosystem (NCDE) have increased in numbers and range extent. Whereas the NCDE population is contiguous with grizzly bear populations in the Canadian Rocky Mountains, genetic evidence suggests the GYE population remains isolated. Recent analyses indicate the ef
Filter Total Items: 83
A unified approach to long-term population monitoring of grizzly bears in the Greater Yellowstone Ecosystem
Long-term wildlife research and monitoring programs strive to maintain consistent data collections and analytical methods. Incorporating new techniques is important but can render data sets incongruent and limit their potential to discern trends in demographic parameters. Integrated population models (IPMs) can address these limitations by combining data sources that may span different periods int
Authors
Matthew J. Gould, Justin Clapp, Mark A. Haroldson, Cecily M. Costello, J. Joshua Nowak, Hans Martin, Michael Ebinger, Daniel D. Bjornlie, Daniel Thompson, Justin A. Dellinger, Matthew Mumma, Paul Lukacs, Frank T. van Manen
Integrating ecological value and charismatic species habitats to prioritize habitats for conservation: A case study from Greater Yellowstone
Expanding human pressure has reduced natural habitats globally and motivated strategies to conserve remaining natural habitats. Decisions about conservation on private lands, however, are typically made by local stakeholders who are motivated by the elements of nature they most highly value. Thus, national prioritization for conservation should be complemented by local analysis of species or habit
Authors
A. J. Hansena, A. Easta, Z. Ashford, C. Crittendena, O. Jakabosky, D. Quinby, Shannon K. Brewer, Frank T. van Manen, Mark A. Haroldson, A. Middleton, N. Robinson, D. M. Theobald
Grizzly bear responses to restrictions of recreation in Yellowstone National Park
Avoiding humans will be more difficult and energetically costly for animals as outdoor recreation increases and people venture farther into wildland areas that provide high-quality habitat for wildlife. Restricting human access can be an attractive management tool to mitigate effects of human recreation activities on wildlife; however, the efficacy of such measures is rarely assessed. In 1982, Yel
Authors
Elise Loggers, Andrea R. Litt, Frank T. van Manen, Mark A. Haroldson, Kerry A. Gunther
Grizzly bear lean body mass, but not fat gain, is inversely correlated with bear density in a changing Greater Yellowstone Ecosystem
No abstract available.
Authors
Andrea Corradini, Mark A. Haroldson, Frank T. van Manen
A summary of grizzly bear distribution in Montana: Application of consistent methods in 2022
No abstract available.
Authors
Cecily M. Costello, J. Dellinger, Jennifer Fortin-Noreus, Mark A. Haroldson, Wayne F. Kasworm, J. E. Tiesberg, Frank T. van Manen
Evidence for density-dependent effects on body composition of a large omnivore in a changing Greater Yellowstone Ecosystem
Understanding the density-dependent processes that drive population demography in a changing world is critical in ecology, yet measuring performance–density relationships in long-lived mammalian species demands long-term data, limiting scientists' ability to observe such mechanisms. We tested performance–density relationships for an opportunistic omnivore, grizzly bears (Ursus arctos, Linnaeus, 17
Authors
Andrea Corradini, Mark A. Haroldson, Francesca Cagnacci, Cecily M. Costello, Daniel D. Bjornlie, Daniel Thompson, Jeremy M. Nicholson, Kerry A. Gunther, Katharine R. Wilmot, Frank T. van Manen
Grizzly bear movement models predict habitat use for nearby populations
Conservation planning and decision-making can be enhanced by ecological models that reliably transfer to times and places beyond those where models were developed. Transferrable models can be especially helpful for species of conservation concern, such as grizzly bears (Ursus arctos). Currently, only four grizzly bear populations remain in the contiguous United States. We evaluated transferability
Authors
Sarah Nelson Sells, Cecily M. Costello, Paul Lukacs, Frank T. van Manen, Mark A. Haroldson, Wayne Kasworm, Justin Tesiberg, Milan Vinks, Daniel D. Bjornlie
Enhancements to population monitoring of Yellowstone grizzly bears
In the Greater Yellowstone Ecosystem, counts of female grizzly bears (Ursus arctos) with cubs-of-the-year (females with cubs) from systematic aerial surveys and opportunistic ground sightings are combined with demographic data to derive annual population estimates. We addressed 2 limitations to the monitoring approach. As part of a rule set, a conservative distance of >30 km currently is used as a
Authors
Frank T. van Manen, Michael Ebinger, Cecily M. Costello, Daniel D. Bjornlie, Justin Clapp, Daniel Thompson, Mark A. Haroldson, Kevin L. Frey, Curtis Hendricks, Jeremy M. Nicholson, Kerry A. Gunther, Katharine R. Wilmot, Hilary Cooley, Jennifer Fortin-Noreus, Pat Hnilicka, Daniel B. Tyers
Genetic architecture and evolution of color variation in American black bears
Color variation is a frequent evolutionary substrate for camouflage in small mammals, but the underlying genetics and evolutionary forces that drive color variation in natural populations of large mammals are mostly unexplained. The American black bear, Ursus americanus (U. americanus), exhibits a range of colors including the cinnamon morph, which has a similar color to the brown bear, U. arctos,
Authors
E. Puckett, I. S. Davis, D. C. Harper, K. Wakamatsu, G. Battu, J. L. Belant, D. E. Beyer, C. Carpenter, A. P. Crupi, M. Davidson, C. S. DePerno, N. Forman, N. L. Fowler, D. L. Garshelis, N. Gould, K. Gunther, Mark A. Haroldson, S. Ito, David. M Kocka, C. Lackey, R. Leahy, C. Lee-Roney, T. Lewis, A. Lutto, K. McGowan, C. Olfenbuttel, M. Orlando, A. Platt, M. D. Pollard, M. Ramaker, Heather Reich, Jaime L. Sajecki, S. K. Sell, J. Strules, S. Thompson, Frank T. van Manen, Craig Whitman, R. Williamson, F. Winslow, C. B. Kaelin, M. S. Marks, G. S. Barsh
Agent-based models for collective animal movement: Proximity-induced state switching
Animal movement is a complex phenomenon where individual movement patterns can be influenced by a variety of factors including the animal’s current activity, available terrain and habitat, and locations of other animals. Motivated by modeling grizzly bear movement in the Greater Yellowstone Ecosystem, this article presents an agent-based model represented in a state-space framework for collective
Authors
Andrew B. Hoegh, Frank T. van Manen, Mark A. Haroldson
Science and Products
Informing Management Options for grizzly bears in a Changing Greater Yellowstone Ecosystem
Project Overview The iconic grizzly bear of the Greater Yellowstone Ecosystem has exhibited a remarkable recovery in response to concerted conservation actions implemented since its listing as threatened under the Endangered Species Act in 1975. However, information regarding the potential effects and timing of climate change in conjunction with increasing human recreation and development will be
Interagency Grizzly Bear Study Team
The Interagency Grizzly Bear Study Team (IGBST) is an interdisciplinary group of scientists and biologists responsible for long-term monitoring and research efforts on grizzly bears in the Greater Yellowstone Ecosystem (GYE). The team was formed by the Department of the Interior (DOI) in 1973 as a direct result of controversy surrounding the closure of open pit garbage dumps within Yellowstone...
NOROCK Large Carnivore Research Program
NOROCK has substantial expertise in large carnivore research, primarily involving species listed as Threatened or Endangered. NOROCK’s Large Carnivore Research Program includes scientists from NOROCK’s Headquarters, West Glacier Field Station, and the Southern Appalachian Field Station. Studies are conducted in a wide variety of landscapes throughout the U.S., as well as international research...
Mortality, morphology, and water chemistry for 6PPD-quinone exposed coho embryos
Understanding evolutionary processes that drive population dynamics is critical in ecology. Measuring the performance-density relationship in long-lived mammalian species demands long-term data, limiting the ability to observe such mechanisms. We tested density-dependent (intrinsic) and density-independent (extrinsic) drivers of body composition of grizzly bears (Ursus arctos) in the Greater Yello
Body composition data of grizzly bears in the Greater Yellowstone Ecosystem 2000-2020
Understanding evolutionary processes that drive population dynamics is critical in ecology. Measuring the performance-density relationship in long-lived mammalian species demands long-term data, limiting the ability to observe such mechanisms. We tested density-dependent (intrinsic) and density-independent (extrinsic) drivers of body composition of grizzly bears (Ursus arctos) in the Greater Yello
Documented known and probable grizzly bear mortalities in the Greater Yellowstone Ecosystem, 2015-2023 (ver. 3.0 April 2024)
We evaluate mortalities for population segments within the DMA by deriving estimates of total mortality for independent-age (equal to or less than 2 years old) females and independent-age males, including estimates of unknown/unreported mortalities based on Cherry et al. (2002). We then determine the total annual mortality rate for these segments as a percent of their respective population estimat
Detection histories of grizzly bears in Grand Teton National Park, 2014-2015
This dataset contains detection histories of grizzly bears in areas of Grand Teton National Park that are open for elk harvest as part of the Elk Reduction Program. Sampling followed a robust design analysis with 6 primary sampling periods of 4 weekly secondary sampling periods each during 2014-2015. In both years, primary sampling periods were in July-August (no elk hunt), September-October (no e
Canine distemper virus antibody titer results for grizzly bears and wolves in the Greater Yellowstone Ecosystem 1984-2014
We investigated the dynamics of canine distemper virus (CDV) in grizzly bears (Ursus arctos) and wolves (Canis lupus) of the Greater Yellowstone Ecosystem using serological data collected from 1984 to 2014. 565 sera samples were obtained from 425 unique grizzly bears (134 females and 291 males) from 1984 to 2014 and 319 sera samples were obtained from 285 unique wolves (130 females and 155 males)
Potential movement paths for male grizzly bear (Ursus arctos) dispersal between the Northern Continental Divide and Greater Yellowstone Ecosystems, 2000-2015
For several decades, grizzly bear (Ursus arctos) populations in the Greater Yellowstone Ecosystem (GYE) and the Northern Continental Divide Ecosystem (NCDE) have increased in numbers and range extent. Whereas the NCDE population is contiguous with grizzly bear populations in the Canadian Rocky Mountains, genetic evidence suggests the GYE population remains isolated. Recent analyses indicate the ef
Filter Total Items: 83
A unified approach to long-term population monitoring of grizzly bears in the Greater Yellowstone Ecosystem
Long-term wildlife research and monitoring programs strive to maintain consistent data collections and analytical methods. Incorporating new techniques is important but can render data sets incongruent and limit their potential to discern trends in demographic parameters. Integrated population models (IPMs) can address these limitations by combining data sources that may span different periods int
Authors
Matthew J. Gould, Justin Clapp, Mark A. Haroldson, Cecily M. Costello, J. Joshua Nowak, Hans Martin, Michael Ebinger, Daniel D. Bjornlie, Daniel Thompson, Justin A. Dellinger, Matthew Mumma, Paul Lukacs, Frank T. van Manen
Integrating ecological value and charismatic species habitats to prioritize habitats for conservation: A case study from Greater Yellowstone
Expanding human pressure has reduced natural habitats globally and motivated strategies to conserve remaining natural habitats. Decisions about conservation on private lands, however, are typically made by local stakeholders who are motivated by the elements of nature they most highly value. Thus, national prioritization for conservation should be complemented by local analysis of species or habit
Authors
A. J. Hansena, A. Easta, Z. Ashford, C. Crittendena, O. Jakabosky, D. Quinby, Shannon K. Brewer, Frank T. van Manen, Mark A. Haroldson, A. Middleton, N. Robinson, D. M. Theobald
Grizzly bear responses to restrictions of recreation in Yellowstone National Park
Avoiding humans will be more difficult and energetically costly for animals as outdoor recreation increases and people venture farther into wildland areas that provide high-quality habitat for wildlife. Restricting human access can be an attractive management tool to mitigate effects of human recreation activities on wildlife; however, the efficacy of such measures is rarely assessed. In 1982, Yel
Authors
Elise Loggers, Andrea R. Litt, Frank T. van Manen, Mark A. Haroldson, Kerry A. Gunther
Grizzly bear lean body mass, but not fat gain, is inversely correlated with bear density in a changing Greater Yellowstone Ecosystem
No abstract available.
Authors
Andrea Corradini, Mark A. Haroldson, Frank T. van Manen
A summary of grizzly bear distribution in Montana: Application of consistent methods in 2022
No abstract available.
Authors
Cecily M. Costello, J. Dellinger, Jennifer Fortin-Noreus, Mark A. Haroldson, Wayne F. Kasworm, J. E. Tiesberg, Frank T. van Manen
Evidence for density-dependent effects on body composition of a large omnivore in a changing Greater Yellowstone Ecosystem
Understanding the density-dependent processes that drive population demography in a changing world is critical in ecology, yet measuring performance–density relationships in long-lived mammalian species demands long-term data, limiting scientists' ability to observe such mechanisms. We tested performance–density relationships for an opportunistic omnivore, grizzly bears (Ursus arctos, Linnaeus, 17
Authors
Andrea Corradini, Mark A. Haroldson, Francesca Cagnacci, Cecily M. Costello, Daniel D. Bjornlie, Daniel Thompson, Jeremy M. Nicholson, Kerry A. Gunther, Katharine R. Wilmot, Frank T. van Manen
Grizzly bear movement models predict habitat use for nearby populations
Conservation planning and decision-making can be enhanced by ecological models that reliably transfer to times and places beyond those where models were developed. Transferrable models can be especially helpful for species of conservation concern, such as grizzly bears (Ursus arctos). Currently, only four grizzly bear populations remain in the contiguous United States. We evaluated transferability
Authors
Sarah Nelson Sells, Cecily M. Costello, Paul Lukacs, Frank T. van Manen, Mark A. Haroldson, Wayne Kasworm, Justin Tesiberg, Milan Vinks, Daniel D. Bjornlie
Enhancements to population monitoring of Yellowstone grizzly bears
In the Greater Yellowstone Ecosystem, counts of female grizzly bears (Ursus arctos) with cubs-of-the-year (females with cubs) from systematic aerial surveys and opportunistic ground sightings are combined with demographic data to derive annual population estimates. We addressed 2 limitations to the monitoring approach. As part of a rule set, a conservative distance of >30 km currently is used as a
Authors
Frank T. van Manen, Michael Ebinger, Cecily M. Costello, Daniel D. Bjornlie, Justin Clapp, Daniel Thompson, Mark A. Haroldson, Kevin L. Frey, Curtis Hendricks, Jeremy M. Nicholson, Kerry A. Gunther, Katharine R. Wilmot, Hilary Cooley, Jennifer Fortin-Noreus, Pat Hnilicka, Daniel B. Tyers
Genetic architecture and evolution of color variation in American black bears
Color variation is a frequent evolutionary substrate for camouflage in small mammals, but the underlying genetics and evolutionary forces that drive color variation in natural populations of large mammals are mostly unexplained. The American black bear, Ursus americanus (U. americanus), exhibits a range of colors including the cinnamon morph, which has a similar color to the brown bear, U. arctos,
Authors
E. Puckett, I. S. Davis, D. C. Harper, K. Wakamatsu, G. Battu, J. L. Belant, D. E. Beyer, C. Carpenter, A. P. Crupi, M. Davidson, C. S. DePerno, N. Forman, N. L. Fowler, D. L. Garshelis, N. Gould, K. Gunther, Mark A. Haroldson, S. Ito, David. M Kocka, C. Lackey, R. Leahy, C. Lee-Roney, T. Lewis, A. Lutto, K. McGowan, C. Olfenbuttel, M. Orlando, A. Platt, M. D. Pollard, M. Ramaker, Heather Reich, Jaime L. Sajecki, S. K. Sell, J. Strules, S. Thompson, Frank T. van Manen, Craig Whitman, R. Williamson, F. Winslow, C. B. Kaelin, M. S. Marks, G. S. Barsh
Agent-based models for collective animal movement: Proximity-induced state switching
Animal movement is a complex phenomenon where individual movement patterns can be influenced by a variety of factors including the animal’s current activity, available terrain and habitat, and locations of other animals. Motivated by modeling grizzly bear movement in the Greater Yellowstone Ecosystem, this article presents an agent-based model represented in a state-space framework for collective
Authors
Andrew B. Hoegh, Frank T. van Manen, Mark A. Haroldson