Article
Biology
Anthony M. Carnahan, Frank T. van Manen, Mark A. Haroldson, Gordon B. Stenhouse, Charles T. Robbins
Summary: Studies show that the cost of uphill movement for grizzly bears increases with speed and slope angle linearly, while uphill travel at slower speeds is more costly than horizontal travel. The most efficient walking speed for grizzly bears is 1.19 m/s, yet bears in the Greater Yellowstone Ecosystem move at an average velocity of 0.61 m/s and prefer near-horizontal slopes. Grizzly bears choose paths across slopes that are 54% less steep and costly than the maximum available slope when traveling uphill or downhill.
JOURNAL OF EXPERIMENTAL BIOLOGY
(2021)
Article
Biodiversity Conservation
Sarah N. Sells, Cecily M. Costello, Paul M. Lukacs, Lori L. Roberts, Milan A. Vinks
Summary: Habitat and corridor mapping are crucial for conservation programs. This study used integrated step selection functions (iSSFs) developed from GPS-collared grizzly bears to predict areas of connectivity and evaluate conservation goals in the US.
BIOLOGICAL CONSERVATION
(2023)
Article
Ecology
Savannah A. Rogers, Charles T. Robbins, Paul D. Mathewson, Anthony M. Carnahan, Frank T. van Manen, Mark A. Haroldson, Warren P. Porter, Taylor R. Rogers, Terence Soule, Ryan A. Long
Summary: The heat dissipation limit theory suggests that the energy available for growth and reproduction in endotherms is constrained by their ability to dissipate heat. Research found that environmental temperature has a significant impact on the behavior and ecological performance of female mammals.
FUNCTIONAL ECOLOGY
(2021)
Article
Ecology
Elise A. Loggers, Andrea R. Litt, Frank T. van Manen, Mark A. Haroldson, Kerry A. Gunther
Summary: As outdoor recreation increases and people venture farther into wildland areas, it becomes more difficult for animals to avoid humans. Restricting human access to wildlife habitats can be an effective tool in mitigating the impact of human recreational activities, but its efficacy is rarely evaluated. A study in Yellowstone National Park found that grizzly bears selectively choose areas designated as bear management areas (BMAs) regardless of whether human access is restricted or not, based on availability of food resources and season.
JOURNAL OF WILDLIFE MANAGEMENT
(2023)
Article
Ecology
Lauren H. Henson, Niko Balkenhol, Robert Gustas, Megan Adams, Jennifer Walkus, William G. Housty, Astrid Stronen, Jason Moody, Christina Service, Donald Reece, Bridgett M. VonHoldt, Iain McKechnie, Ben F. Koop, Chris T. Darimont
Summary: Landscape genetic analyses of grizzly bear populations in coastal British Columbia, Canada, revealed the possible effects of complex landscape and human influences on genetic structure. The study found spatial alignment between Indigenous language families and grizzly bear genetic groups, suggesting that people and wildlife populations may have been shaped by the landscape in similar ways. This research provides new genetic evidence to support locally led management of grizzly bears in the future.
ECOLOGY AND SOCIETY
(2021)
Article
Biodiversity Conservation
Jason I. Ransom, Andrea L. Lyons, Katherine C. Hegewisch, Meade Krosby
Summary: As Earth faces a crisis of biodiversity loss, reintroduction of imperiled species has become an important tool toward mitigating extirpation. Current habitat quality for a reintroduced species may change dramatically under future climate scenarios, undermining or supporting species conservation efforts. Models designed to understand such change must consider the niche plasticity of a species to assess the costs and benefits of reintroduction.
BIOLOGICAL CONSERVATION
(2023)
Article
Multidisciplinary Sciences
Aurora Donatelli, Gianluca Mastrantonio, Paolo Ciucci
Summary: This study examines the circadian rhythms and activity patterns of Apennine brown bears. The results show a bimodal curve of activity, with peaks around sunrise and sunset. Bears exhibit higher movement rates during the mating season and increase their movement rate near roads and settlements during spring and late summer, suggesting a trade-off between foraging opportunities and risk avoidance.
SCIENTIFIC REPORTS
(2022)
Article
Food Science & Technology
Nikolina Kelava Ugarkovic, Miljenko Konjacic, Josip Malnar, Kristijan Tomljanovic, Nikica Sprem, Damir Ugarkovic
Summary: This study aimed to determine the effects of sex and age on the proximate chemical composition, fatty acid profile, and lipid indices of brown bear meat. Results showed that age had an effect on the traits analyzed, while no significant differences were found related to sex.
Article
Forestry
Angela Anna Rositi, Giovanna Jona Lasinio, Paolo Ciucci
Summary: The availability of hard mast and soft-mast producing species is influenced by forest typology, historical forestry practices, and topographical features. Herb cover is negatively affected by terrain steepness and basal area, while ant richness is associated with forest volume and density. These findings provide valuable information for forest management practices to support the conservation of Apennine bears in the long term.
Article
Biodiversity Conservation
Neda Bogdanovic, Andreas Zedrosser, Anne G. Hertel, Alejandra Zarzo-Arias, Dusko Cirbvic
Summary: Natural habitats are being degraded and fragmented due to human expansion, threatening the survival of many species. Understanding species distribution and identifying movement corridors is crucial for conservation. Serbia's geographical position plays a significant role in connecting bear metapopulations. The study predicts suitable habitats and proposes measures for habitat permeability to benefit not only bears but also other species in the region.
GLOBAL ECOLOGY AND CONSERVATION
(2023)
Article
Genetics & Heredity
Vincenzo Buono, Salvatore Burgio, Nicole Macri, Giovanni Catania, Heidi C. Hauffe, Nadia Mucci, Francesca Davoli
Summary: An assessment of the genetic diversity and structure of two endangered brown bear populations in Italy was conducted to propose a cost-effective management protocol for populations with low genetic variation. By analyzing microsatellite loci, the study identified the most effective STR marker sets for evaluating genetic diversity and individual discrimination. The findings indicate that the Uam population should be considered a conservation priority due to its depleted genetic variability.
Article
Zoology
Frank T. van Manen, Michael R. Ebinger, Cecily M. Costello, Daniel D. Bjornlie, Justin G. Clapp, Daniel J. Thompson, Mark A. Haroldson, Kevin L. Frey, Curtis Hendricks, Jeremy M. Nicholson, Kerry A. Gunther, Katharine R. Wilmot, Hilary S. Cooley, Jennifer K. Fortin-Noreus, Pat Hnilicka, Daniel B. Tyers
Summary: This study addresses two limitations in the monitoring approach of grizzly bear populations by improving the distance criteria and using generalized additive models. Results show that a distance criterion of 12-16 km maximizes classification performance and minimizes estimation bias. The GAM approach allows detection of directional changes in population trends and provides early warning metrics and information about stability.
Article
Agriculture, Dairy & Animal Science
Ana Balseiro, Laura Polledo, Jose Tunon, Juan Francisco Garcia Marin
Summary: A captive female Eurasian brown bear in her 24th year of age gave birth to a stillborn cub with multiple malformations resulting from anomalous neural tube development. These malformations, including anencephaly, hypoplasia, micromyelia, severe myelodysplasia, syringomyelia, and spina bifida, have not been previously reported in bears. The cause of the malformations remains unknown, but the mother's advanced age and/or folic acid deficiency may be possible factors. Supplementing the mother with folate before and during early pregnancy could help prevent the occurrence of neural tube defects in captive bears, thus safeguarding the future generations of this endangered species.
Article
Biodiversity Conservation
James P. Kilfoil, Thomas P. Quinn, Aaron J. Wirsing
Summary: Humans can significantly alter the temporal activity of wildlife, and the ecological consequences of such shifts can lead to reduced fitness, increased competition, and trophic cascades. This study examined the potential of human disturbance as a temporal-shield for brown bears foraging on sockeye salmon in southwestern Alaska. The results showed that all bears avoided peak times of human activity, but socially-subordinate subadult bears had higher overlap with humans compared to females with cubs and single adults. The findings suggest that human-disturbance can have complex effects on large carnivores and may provide increased foraging opportunities for socially subordinate, but more human-tolerant individuals.
GLOBAL ECOLOGY AND CONSERVATION
(2023)
Article
Biodiversity Conservation
Francesco Maroso, Giada Padovani, Victor Hugo Munoz Mora, Francesco Giannelli, Emiliano Trucchi, Giorgio Bertorelle
Summary: Reduction in population size and its predicted effects on population fitness is a major concern for endangered species. Genetic rescue (GR) is a controversial approach that introduces compatible individuals to reduce the genetic load and restore fitness of declining populations. The study on Apennine brown bears showed that introducing individuals with higher fitness and lower levels of deleterious mutations can rapidly increase fitness but also result in some loss of ancestry. Doubling the population size without genetic rescue gradually improved fitness without losing ancestry, making it the best strategy for Apennine brown bear conservation.
CONSERVATION BIOLOGY
(2023)
Article
Ecology
Frank T. van Manen, Mark A. Haroldson, Daniel D. Bjornlie, Michael R. Ebinger, Daniel J. Thompson, Cecily M. Costello, Gary C. White
JOURNAL OF WILDLIFE MANAGEMENT
(2016)
Article
Biochemistry & Molecular Biology
Pauline L. Kamath, Mark A. Haroldson, Gordon Luikart, David Paetkau, Craig Whitman, Frank T. Van Manen
Article
Ecology
Michael R. Ebinger, Mark A. Haroldson, Frank T. van Manen, Cecily M. Costello, Daniel D. Bjornlie, Daniel J. Thompson, Kerry A. Gunther, Jennifer K. Fortin, Justin E. Teisberg, Shannon R. Pils, P. J. White, Steven L. Cain, Paul C. Cross
Article
Multidisciplinary Sciences
Cecily M. Costello, Steven L. Cain, Shannon Pils, Leslie Frattaroli, Mark A. Haroldson, Frank T. van Manen
Article
Zoology
Joseph W. Hinton, Annaliese K. Ashley, Justin A. Dellinger, John L. Gittleman, Frank T. van Manen, Michael J. Chamberlain
JOURNAL OF MAMMALOGY
(2017)
Article
Multidisciplinary Sciences
Shyamala Ratnayeke, Frank T. van Manen, Gopalasamy Reuben Clements, Noor Azleen Mohd Kulaimi, Stuart P. Sharp
Article
Ecology
Joseph W. Hinton, John L. Gittleman, Frank T. van Manen, Michael J. Chamberlain
ECOLOGY AND EVOLUTION
(2018)
Article
Multidisciplinary Sciences
Joseph W. Hinton, Christine Proctor, Marcella J. Kelly, Frank T. van Manen, Michael R. Vaughan, Michael J. Chamberlain
Article
Ecology
Paul C. Cross, Frank T. van Manen, Mafalda Viana, Emily S. Almberg, Daniel Bachen, Ellen E. Brandell, Mark A. Haroldson, Peter J. Hudson, Daniel R. Stahler, Douglas W. Smith
ECOLOGY AND EVOLUTION
(2018)
Article
Ecology
Savannah A. Rogers, Charles T. Robbins, Paul D. Mathewson, Anthony M. Carnahan, Frank T. van Manen, Mark A. Haroldson, Warren P. Porter, Taylor R. Rogers, Terence Soule, Ryan A. Long
Summary: The heat dissipation limit theory suggests that the energy available for growth and reproduction in endotherms is constrained by their ability to dissipate heat. Research found that environmental temperature has a significant impact on the behavior and ecological performance of female mammals.
FUNCTIONAL ECOLOGY
(2021)
Article
Biology
Anthony M. Carnahan, Frank T. van Manen, Mark A. Haroldson, Gordon B. Stenhouse, Charles T. Robbins
Summary: Studies show that the cost of uphill movement for grizzly bears increases with speed and slope angle linearly, while uphill travel at slower speeds is more costly than horizontal travel. The most efficient walking speed for grizzly bears is 1.19 m/s, yet bears in the Greater Yellowstone Ecosystem move at an average velocity of 0.61 m/s and prefer near-horizontal slopes. Grizzly bears choose paths across slopes that are 54% less steep and costly than the maximum available slope when traveling uphill or downhill.
JOURNAL OF EXPERIMENTAL BIOLOGY
(2021)
Article
Ecology
Nathaniel R. Bowersock, Andrea R. Litt, Jerod A. Merkle, Kerry A. Gunther, Frank T. van Manen
Summary: The study investigated the impact of spring food resources on American black bears, finding that their movements were influenced by the quality of vegetative food resources. Despite being described as opportunistic foragers, the results suggest that black bears actively seek out areas with high-quality food when available.
Article
Ecology
Nathaniel R. Bowersock, Andrea R. Litt, Michael A. Sawaya, Kerry A. Gunther, Frank T. van Manen
Summary: The study examines the influence of resource availability on the distribution and density of American black bears in Yellowstone National Park. Using genetic sampling and spatially explicit capture-recapture models, the researchers found that black bear density was higher in forested areas compared to non-forested areas. Female black bears had higher densities than males in 2017. The study provides the first spatially explicit estimates of black bear density in an ecosystem that contains a diverse range of large mammal species.
JOURNAL OF WILDLIFE MANAGEMENT
(2023)
Article
Ecology
Elise A. Loggers, Andrea R. Litt, Frank T. van Manen, Mark A. Haroldson, Kerry A. Gunther
Summary: As outdoor recreation increases and people venture farther into wildland areas, it becomes more difficult for animals to avoid humans. Restricting human access to wildlife habitats can be an effective tool in mitigating the impact of human recreational activities, but its efficacy is rarely evaluated. A study in Yellowstone National Park found that grizzly bears selectively choose areas designated as bear management areas (BMAs) regardless of whether human access is restricted or not, based on availability of food resources and season.
JOURNAL OF WILDLIFE MANAGEMENT
(2023)