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
Filter Total Items: 83
Temporal, spatial, and environmental influences on the demographics of grizzly bears in the Greater Yellowstone Ecosystem
During the past 2 decades, the grizzly bear (Ursus arctos) population in the Greater Yellowstone Ecosystem (GYE) has increased in numbers and expanded in range. Understanding temporal, environmental, and spatial variables responsible for this change is useful in evaluating what likely influenced grizzly bear demographics in the GYE and where future management efforts might benefit conservation and
Authors
Charles C. Schwartz, Mark A. Haroldson, Gary C. White, Richard B. Harris, Steve Cherry, Kim A. Keating, Dave Moody, Christopher Servheen
Distribution of grizzly bears in the Greater Yellowstone Ecosystem, 2004
The US Fish and Wildlife Service (USFWS) proposed delisting the Yellowstone grizzly bear (Ursus arctos horribilis) in November 2005. Part of that process required knowledge of the most current distribution of the species. Here, we update an earlier estimate of occupied range (1990–2000) with data through 2004. We used kernel estimators to develop distribution maps of occupied habitats based on ini
Authors
C.C. Schwartz, M.A. Haroldson, K. Gunther, D. Moody
Yellowstone grizzly bear investigations: Annual report of the Interagency Grizzly Bear Study Team, 2004
The contents of this Annual Report summarize results of monitoring and research from the 2004 field season. The report also contains a summary of nuisance grizzly bear (Ursus arctos horribilis) management actions.
The study team continues to work on issues associated with counts of unduplicated females with cubs-of-the-year (COY). These counts are used to establish a minimum population size, which
Changing numbers of spawning cutthroat trout in tributary streams of Yellowstone Lake and estimates of grizzly bears visiting streams from DNA
Spawning Yellowstone cutthroat trout (Oncorhynchus clarki) provide a source of highly digestible energy for grizzly bears (Ursus arctos) that visit tributary streams to Yellowstone Lake during the spring and early summer. During 1985–87, research documented grizzly bears fishing on 61% of the 124 tributary streams to the lake. Using track measurements, it was estimated that a minimum of 44 grizzly
Authors
M.A. Haroldson, K.A. Gunther, Daniel P. Reinhart, S.R. Podruzny, C. Cegelski, L. Waits, T.C. Wyman, J. Smith
Consumption of pondweed rhizomes by Yellowstone grizzly bears
Pondweeds (Potamogeton spp.) are common foods of waterfowl throughout the Northern Hemisphere. However, consumption of pondweeds by bears has been noted only once, in Russia. We documented consumption of pondweed rhizomes by grizzly bears (Ursus arctos) in the Yellowstone region, 1977-96, during investigations of telemetry locations obtained from 175 radiomarked bears. We documented pondweed excav
Authors
D.J. Mattson, S.R. Podruzny, M.A. Haroldson
Grizzly bear-human conflicts in the Yellowstone ecosystem, 1992-2000
For many years, the primary strategy for managing grizzly bears (Ursus arctos) that came into conflict with humans in the Greater Yellowstone Ecosystem (GYE) was to capture and translocate the offending bears away from conflict sites. Translocation usually only temporarily alleviated the problems and most often did not result in long-term solutions. Wildlife managers needed to be able to predict t
Authors
K.A. Gunther, M.A. Haroldson, S.L. Cain, J. Copeland, K. Frey, C.C. Schwartz
Possible effects of elk harvest on fall distribution of grizzly bears in the Greater Yellowstone Ecosystem
The tradition of early elk (Cervus elaphus) hunting seasons adjacent to Yellowstone National Park (YNP), USA, provides grizzly bears (Ursus arctos horribilis) with ungulate remains left by hunters. We investigated the fall (Aug–Oct) distribution of grizzly bears relative to the boundaries of YNP and the opening of September elk hunting seasons. Based on results from exact tests of conditional ind
Authors
M.A. Haroldson, C.C. Schwartz, S. Cherry, D. Moody
Use of naturally occurring mercury to determine the importance of cutthroat trout to Yellowstone grizzly bears
Spawning cutthroat trout (Oncorhynchus clarki (Richardson, 1836)) are a potentially important food resource for grizzly bears (Ursus arctos horribilis Ord, 1815) in the Greater Yellowstone Ecosystem. We developed a method to estimate the amount of cutthroat trout ingested by grizzly bears living in the Yellowstone Lake area. The method utilized (i) the relatively high, naturally occurring concentr
Authors
L.A. Felicetti, C.C. Schwartz, R. O. Rye, K.A. Gunther, J. G. Crock, M.A. Haroldson, L. Waits, C.T. Robbins
Yellowstone grizzly bear investigations: Annual report of the Interagency Grizzly Bear Study Team, 2003
The contents of this Annual Report summarize results of monitoring and research from the 2003 field season. The report also contains a summary of nuisance grizzly bear (Ursus arctos horribilis) management actions.
The study team continues to work on issues associated with counts of unduplicated females with cubs-of-the-year (COY). These counts are used to establish a minimum population size, which
Modeling survival: application of the Andersen-Gill model to Yellowstone grizzly bears
Wildlife ecologists often use the Kaplan-Meier procedure or Cox proportional hazards model to estimate survival rates, distributions, and magnitude of risk factors. The Andersen-Gill formulation (A-G) of the Cox proportional hazards model has seen limited application to mark-resight data but has a number of advantages, including the ability to accommodate left-censored data, time-varying covariat
Authors
Christopher J. Johnson, Mark S. Boyce, Charles C. Schwartz, Mark A. Haroldson
Use of sulfur and nitrogen stable isotopes to determine the importance of whitebark pine nuts to Yellowstone grizzly bears
Whitebark pine (Pinus albicaulis) is a masting species that produces relatively large, fat- and protein-rich nuts that are consumed by grizzly bears (Ursus arctos horribilis). Trees produce abundant nut crops in some years and poor crops in other years. Grizzly bear survival in the Greater Yellowstone Ecosystem is strongly linked to variation in pine-nut availability. Because whitebark pine trees
Authors
L.A. Felicetti, C.C. Schwartz, R. O. Rye, M.A. Haroldson, K.A. Gunther, D.L. Phillips, C.T. Robbins
Science and Products
Filter Total Items: 83
Temporal, spatial, and environmental influences on the demographics of grizzly bears in the Greater Yellowstone Ecosystem
During the past 2 decades, the grizzly bear (Ursus arctos) population in the Greater Yellowstone Ecosystem (GYE) has increased in numbers and expanded in range. Understanding temporal, environmental, and spatial variables responsible for this change is useful in evaluating what likely influenced grizzly bear demographics in the GYE and where future management efforts might benefit conservation and
Authors
Charles C. Schwartz, Mark A. Haroldson, Gary C. White, Richard B. Harris, Steve Cherry, Kim A. Keating, Dave Moody, Christopher Servheen
Distribution of grizzly bears in the Greater Yellowstone Ecosystem, 2004
The US Fish and Wildlife Service (USFWS) proposed delisting the Yellowstone grizzly bear (Ursus arctos horribilis) in November 2005. Part of that process required knowledge of the most current distribution of the species. Here, we update an earlier estimate of occupied range (1990–2000) with data through 2004. We used kernel estimators to develop distribution maps of occupied habitats based on ini
Authors
C.C. Schwartz, M.A. Haroldson, K. Gunther, D. Moody
Yellowstone grizzly bear investigations: Annual report of the Interagency Grizzly Bear Study Team, 2004
The contents of this Annual Report summarize results of monitoring and research from the 2004 field season. The report also contains a summary of nuisance grizzly bear (Ursus arctos horribilis) management actions.
The study team continues to work on issues associated with counts of unduplicated females with cubs-of-the-year (COY). These counts are used to establish a minimum population size, which
Changing numbers of spawning cutthroat trout in tributary streams of Yellowstone Lake and estimates of grizzly bears visiting streams from DNA
Spawning Yellowstone cutthroat trout (Oncorhynchus clarki) provide a source of highly digestible energy for grizzly bears (Ursus arctos) that visit tributary streams to Yellowstone Lake during the spring and early summer. During 1985–87, research documented grizzly bears fishing on 61% of the 124 tributary streams to the lake. Using track measurements, it was estimated that a minimum of 44 grizzly
Authors
M.A. Haroldson, K.A. Gunther, Daniel P. Reinhart, S.R. Podruzny, C. Cegelski, L. Waits, T.C. Wyman, J. Smith
Consumption of pondweed rhizomes by Yellowstone grizzly bears
Pondweeds (Potamogeton spp.) are common foods of waterfowl throughout the Northern Hemisphere. However, consumption of pondweeds by bears has been noted only once, in Russia. We documented consumption of pondweed rhizomes by grizzly bears (Ursus arctos) in the Yellowstone region, 1977-96, during investigations of telemetry locations obtained from 175 radiomarked bears. We documented pondweed excav
Authors
D.J. Mattson, S.R. Podruzny, M.A. Haroldson
Grizzly bear-human conflicts in the Yellowstone ecosystem, 1992-2000
For many years, the primary strategy for managing grizzly bears (Ursus arctos) that came into conflict with humans in the Greater Yellowstone Ecosystem (GYE) was to capture and translocate the offending bears away from conflict sites. Translocation usually only temporarily alleviated the problems and most often did not result in long-term solutions. Wildlife managers needed to be able to predict t
Authors
K.A. Gunther, M.A. Haroldson, S.L. Cain, J. Copeland, K. Frey, C.C. Schwartz
Possible effects of elk harvest on fall distribution of grizzly bears in the Greater Yellowstone Ecosystem
The tradition of early elk (Cervus elaphus) hunting seasons adjacent to Yellowstone National Park (YNP), USA, provides grizzly bears (Ursus arctos horribilis) with ungulate remains left by hunters. We investigated the fall (Aug–Oct) distribution of grizzly bears relative to the boundaries of YNP and the opening of September elk hunting seasons. Based on results from exact tests of conditional ind
Authors
M.A. Haroldson, C.C. Schwartz, S. Cherry, D. Moody
Use of naturally occurring mercury to determine the importance of cutthroat trout to Yellowstone grizzly bears
Spawning cutthroat trout (Oncorhynchus clarki (Richardson, 1836)) are a potentially important food resource for grizzly bears (Ursus arctos horribilis Ord, 1815) in the Greater Yellowstone Ecosystem. We developed a method to estimate the amount of cutthroat trout ingested by grizzly bears living in the Yellowstone Lake area. The method utilized (i) the relatively high, naturally occurring concentr
Authors
L.A. Felicetti, C.C. Schwartz, R. O. Rye, K.A. Gunther, J. G. Crock, M.A. Haroldson, L. Waits, C.T. Robbins
Yellowstone grizzly bear investigations: Annual report of the Interagency Grizzly Bear Study Team, 2003
The contents of this Annual Report summarize results of monitoring and research from the 2003 field season. The report also contains a summary of nuisance grizzly bear (Ursus arctos horribilis) management actions.
The study team continues to work on issues associated with counts of unduplicated females with cubs-of-the-year (COY). These counts are used to establish a minimum population size, which
Modeling survival: application of the Andersen-Gill model to Yellowstone grizzly bears
Wildlife ecologists often use the Kaplan-Meier procedure or Cox proportional hazards model to estimate survival rates, distributions, and magnitude of risk factors. The Andersen-Gill formulation (A-G) of the Cox proportional hazards model has seen limited application to mark-resight data but has a number of advantages, including the ability to accommodate left-censored data, time-varying covariat
Authors
Christopher J. Johnson, Mark S. Boyce, Charles C. Schwartz, Mark A. Haroldson
Use of sulfur and nitrogen stable isotopes to determine the importance of whitebark pine nuts to Yellowstone grizzly bears
Whitebark pine (Pinus albicaulis) is a masting species that produces relatively large, fat- and protein-rich nuts that are consumed by grizzly bears (Ursus arctos horribilis). Trees produce abundant nut crops in some years and poor crops in other years. Grizzly bear survival in the Greater Yellowstone Ecosystem is strongly linked to variation in pine-nut availability. Because whitebark pine trees
Authors
L.A. Felicetti, C.C. Schwartz, R. O. Rye, M.A. Haroldson, K.A. Gunther, D.L. Phillips, C.T. Robbins