Hair cortisol concentration as a noninvasive measure of long-term stress in free-ranging grizzly bears (Ursus arctos): considerations with implications for other wildlife

Human-caused landscape change negatively affects the sustainability of many wildlife populations. In Alberta, Canada, grizzly bears ( Ursus arctos L., 1758) live in one of the most populated and heavily exploited landscapes in which the species survives. Long-term physiological stress in individual animals may be the predominant mechanism linking landscape change with impaired wildlife population health. Hair cortisol concentration has been validated as a biomarker of long-term stress in humans and domestic animals; however, limited work has examined factors that may affect its measurement or interpretation. We have measured cortisol in as few as five guard hairs of a grizzly bear and have identified factors influencing hair cortisol concentration in this species. Hair cortisol varies with hair type, body region, and capture method. It is not influenced by colour, age, sex, environmental exposure (18 days), or prolonged laboratory storage (>1 year) and does not vary along the length of the hair shaft. Recommendations for prudent use of hair cortisol analysis in grizzly bears are discussed with implications for the development of hair cortisol concentration as a tool to monitor long-term stress in other wildlife.

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The Effect of Body Region on Hair Cortisol Concentration in Common Marmosets (Callithrix jacchus)

Comparative Medicine ◽

10.30802/aalas-cm-20-000091 ◽

2021 ◽

Author(s):

Evelyn E Bartling-John ◽

Kimberley A Phillips

Keyword(s):

Callithrix Jacchus ◽

Cortisol Concentration ◽

The Body ◽

Body Region ◽

Research Model ◽

Hair Cortisol ◽

Social Stimuli ◽

Common Marmosets ◽

Hpa Axis Activity

Common marmosets (Callithrix jacchus) are a valuable research model for the study of neuroscience and the biologicimpact of aging due to their adaptivity, physiologic characteristics, and ease of handling for experimental manipulations. Quantification of cortisol in hair provides a noninvasive, retrospective biomarker of hypothalamics-pituitary-adrenal (HPA)axis activity and information on animal wellbeing, including responses to environmental and social stimuli. To obtain valid and reliable measurements of long-term HPA activity, we investigated the variability of cortisol concentration in the hair depending on the body region of marmosets. Hair was collected from the back and tail of 9 adult common marmosets during annual health screenings (male n = 3; female n = 6) and these samples were analyzed for cortisol via methanol extraction and enzyme immunoassay. We found that hair cortisol concentration differed between the tail and back regions, with the tail samples having a significantly higher cortisol concentration. These results indicate intraindividual and interindividual comparisons of hair cortisol concentration should use hair obtained from the same body region in marmosets.

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Scat detection dogs in wildlife research and management: application to grizzly and black bears in the Yellowhead Ecosystem, Alberta, Canada

Canadian Journal of Zoology ◽

10.1139/z04-020 ◽

2004 ◽

Vol 82 (3) ◽

pp. 475-492 ◽

Cited By ~ 142

Author(s):

Samuel K Wasser ◽

Barbara Davenport ◽

Elizabeth R Ramage ◽

Kathleen E Hunt ◽

Margaret Parker ◽

...

Keyword(s):

Ursus Arctos ◽

Physiological Stress ◽

Black Bear ◽

Reproductive Activity ◽

Grizzly Bears ◽

Grizzly Bear ◽

Fecal Cortisol ◽

The North ◽

Promising Tool ◽

Northern Portion

We report the development and application of a method using domestic dogs (Canis familiaris Linnaeus, 1758) to systematically locate wildlife scat over large remote areas. Detection dogs are chosen for their strong object orientation, high play drive, and willingness to strive for a reward. Dogs were trained to detect grizzly bear (Ursus arctos Linnaeus, 1758) and black bear (Ursus americanus Pallas, 1780) scats over a 5200-km2 area of the Yellowhead Ecosystem, Alberta, Canada. DNA from scat provided the species and (for grizzly bears only) sex and individual identities of the animal at each location. Concentrations of fecal cortisol and progesterone metabolites from these same grizzly bear scats provided indices of physiological stress and reproductive activity (in females), respectively. Black and grizzly bears were most concentrated in the northern portion of the multiuse study area, where food is most abundant yet poaching-related mortality appears to be heaviest. Physiologic stress was also lowest and female reproductive activity correspondingly highest for grizzly bears in the north. The scat-based distributions corresponded to concurrently collected hair-snag data in 1999 and global positioning system radiotelemetry data (of grizzly bears) in 1999 and 2001. Results suggest that the scat dog detection methodology provides a promising tool for addressing a variety of management and research questions in the wildlife sciences.

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Quantifying long-term stress in brown bears with the hair cortisol concentration: a biomarker that may be confounded by rapid changes in response to capture and handling

Conservation Physiology ◽

10.1093/conphys/cou026 ◽

2014 ◽

Vol 2 (1) ◽

pp. cou026-cou026 ◽

Cited By ~ 38

Author(s):

M. Cattet ◽

B. J. Macbeth ◽

D. M. Janz ◽

A. Zedrosser ◽

J. E. Swenson ◽

...

Keyword(s):

Cortisol Concentration ◽

Hair Cortisol ◽

Brown Bears ◽

Rapid Changes

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A grizzly bear from the Middle Wisconsin of Woodbridge, Ontario

Canadian Journal of Earth Sciences ◽

10.1139/e76-036 ◽

1976 ◽

Vol 13 (2) ◽

pp. 341-347 ◽

Cited By ~ 4

Author(s):

Charles S. Churcher ◽

Alan V. Morgan

Keyword(s):

Ursus Arctos ◽

Grizzly Bears ◽

Grizzly Bear ◽

Bone Fragment ◽

Mammuthus Primigenius ◽

Ursus Arctos Horribilis ◽

Before And After ◽

Lake Simcoe ◽

Left Humerus ◽

Woolly Mammoth

The distal end of the left humerus of a grizzly bear, Ursus arctos, has been recovered from above the Early Wisconsin Sunnybrook Till at Woodbridge, Ontario, from the same horizon that previously has yielded remains of the woolly mammoth, Mammuthus primigenius. The age of these specimens is estimated at 40 000–50 000 years BP, within the mid-Wisconsin, Port Talbot Interstadial. The only other recognized Canadian record of a grizzly bear east of Manitoba is from a gravel sequence at Barrie, near Lake Simcoe, Ontario, dated from a bone fragment to 11 700 ± 250 years BP. A specimen recovered in Toronto in 1913 from an Early Wisconsin horizon is also considered to represent the grizzly. Bears of the grizzly type, Ursus arctos-horribilis were present in Ontario before and after the Early and Late Wisconsin ice advances.

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Predation on moose and caribou by radio-collared grizzly bears in east central Alaska

Canadian Journal of Zoology ◽

10.1139/z88-369 ◽

1988 ◽

Vol 66 (11) ◽

pp. 2492-2499 ◽

Cited By ~ 40

Author(s):

R. D. Boertje ◽

W. C. Gasaway ◽

D. V. Grangaard ◽

D. G. Kelleyhouse

Keyword(s):

Important Implication ◽

Rangifer Tarandus ◽

Ursus Arctos ◽

Prey Availability ◽

Grizzly Bears ◽

Grizzly Bear ◽

East Central ◽

Specific Factors ◽

Low Levels ◽

Predation Rates

Radio-collared grizzly bears (Ursus arctos) were sighted daily for approximately 1-month periods during spring, summer, and fall to estimate predation rates. Predation rates on adult moose (Alces alces) were highest in spring, lowest in summer, and intermediate in fall. The highest kill rates were by male grizzlies killing cow moose during the calving period. We estimated that each adult male grizzly killed 3.3–3.9 adult moose annually, each female without cub(s) killed 0.6–0.8 adult moose and 0.9–1.0 adult caribou (Rangifer tarandus) annually, and each adult bear killed at least 5.4 moose calves annually. Grizzly predation rates on calves and grizzly density were independent of moose density and are probably more related to area-specific factors, e.g., availability of alternative foods. An important implication of our results is that managers should not allow moose densities to decline to low levels, because grizzlies can have a greater relative impact on low- than on high-density moose populations and because grizzly predation can be difficult to reduce. Grizzly bears were primarily predators, rather than scavengers, in this area of low prey availability (11 moose/grizzly bear); bears killed four times more animal biomass than they scavenged.

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Association of screen time with long-term stress and temperament in preschoolers: results from the DAGIS study

European Journal of Pediatrics ◽

10.1007/s00431-020-03686-5 ◽

2020 ◽

Vol 179 (11) ◽

pp. 1805-1812

Author(s):

Marja H. Leppänen ◽

Katri Sääksjärvi ◽

Henna Vepsäläinen ◽

Carola Ray ◽

Pauliina Hiltunen ◽

...

Keyword(s):

Socioeconomic Status ◽

Preschool Children ◽

Young Children ◽

Screen Time ◽

Effortful Control ◽

Cortisol Concentration ◽

Hair Cortisol ◽

Moderating Role

Abstract Screen time is increasing rapidly in young children. The aim of this study was to examine associations of long-term stress and temperament with screen time in Finnish preschool children and the moderating role of socioeconomic status. Cross-sectional DAGIS data were utilized. Long-term stress was assessed using hair cortisol concentration, indicating values of the past 2 months. Temperament was reported by the parents using the Children’s Behavior Questionnaire (the Very Short Form), and three broad temperament dimensions were constructed: surgency, negative affectivity, and effortful control. Screen time was reported by the parents over 7 days. The highest education level in the household was used as an indicator of socioeconomic status. In total, 779 children (mean age, 4.7 ± 0.9 years, 52% boys) were included in the study. Of the temperament dimensions, a higher effortful control was associated with less screen time (B = − 6.70, p = 0.002). There was no evidence for an association between hair cortisol concentration and screen time nor a moderating role of socioeconomic status in the associations (p > 0.05). Conclusion: Our findings indicate that preschool children with a higher score in effortful control had less screen time. Because effortful control reflects general self-regulatory abilities, promoting these skills may be effective in reducing screen time in young children. What is Known: • Screen time has increased rapidly during the last decades, and higher screen time has been linked with numerous adverse health consequences in children. • There are no previous studies investigating associations of long-term stress and temperament with screen time in young children. What is New: • Of the temperament dimensions, effortful control was associated with higher screen time in preschool children, but there was no association found between long-term stress and screen time. • Since effortful control reflects general self-regulatory abilities, promoting these skills may be effective in reducing screen time in young children.

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A study of predominant aerobic microflora of black bears (Ursus americanus) and grizzly bears (Ursus arctos) in northwestern Alberta

Canadian Journal of Microbiology ◽

10.1139/m87-167 ◽

1987 ◽

Vol 33 (11) ◽

pp. 949-954 ◽

Cited By ~ 11

Author(s):

L. J. Goatcher ◽

M. W. Barrett ◽

R. N. Coleman ◽

A. W. L. Hawley ◽

A. A. Qureshi

Keyword(s):

Soil Bacteria ◽

Ursus Arctos ◽

Random Distribution ◽

Ursus Americanus ◽

Black Bear ◽

Black Bears ◽

Grizzly Bears ◽

Grizzly Bear ◽

Streptococcus Species ◽

Generic Composition

Swab specimens were obtained from nasal, rectal, and preputial or vaginal areas of 37 grizzly and 17 black bears, captured during May to June of 1981 to 1983, to determine the types and frequency of predominant aerobic microflora. Bacterial genera most frequently isolated from bears were Escherichia, Citrobacter, Hafnia, Proteus, Staphylococcus, and Streptococcus species, comprising about 65% of the isolates. Erwinia, Xanthomonas, Agrobacterium, Rhizobium, and Gluconobacter/Acetobacter were also isolated but at lower frequencies (< 5%). Comparison of bacterial generic composition using similarity quotient values showed no appreciable differences between grizzly and black bear flora. Also, no outstanding differences in bacterial generic composition were observed among grizzly bear samples; however, differences were noted among black bear samples. Fungal genera most commonly encountered included Cryptococcus, Rhodotorula, Cladosporium, Penicillium, Sporobolomyces, and Candida. In general, the microflora of both bear types were marked by generic diversity and random distribution. The majority of microorganisms isolated from the plant samples in the study area were also found in bear samples. This observation and the presence of certain water and soil bacteria in samples from bears suggest that the predominant microflora of both grizzly and black bears were transient and probably influenced by their foraging habits and surrounding environments.

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Comparison of methanol and isopropanol as wash solvents for determination of hair cortisol concentration in grizzly bears and polar bears

MethodsX ◽

10.1016/j.mex.2017.01.004 ◽

2017 ◽

Vol 4 ◽

pp. 68-75 ◽

Cited By ~ 6

Author(s):

Thomas Kroshko ◽

Luciene Kapronczai ◽

Marc R.L. Cattet ◽

Bryan J. Macbeth ◽

Gordon B. Stenhouse ◽

...

Keyword(s):

Cortisol Concentration ◽

Grizzly Bears ◽

Polar Bears ◽

Hair Cortisol

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An Investigation of Hair Cortisol Concentration across Body Sites and within Hair shaft

Clinical Medicine Insights Endocrinology and Diabetes ◽

10.4137/cmed.s4465 ◽

2010 ◽

Vol 3 ◽

pp. CMED.S4465 ◽

Cited By ~ 10

Author(s):

Christopher F. Sharpley ◽

Kathleen G. Kauter ◽

James R. Mcfarlane

Keyword(s):

Young Male ◽

Hair Shaft ◽

Cortisol Concentration ◽

Cortisol Response ◽

Hair Cortisol ◽

Shaft Length ◽

Male And Female ◽

Environmental Demand

Cortisol concentrations in hair collected from young male and female adults were assayed and compared for differences along shaft length and between body sites. No significant differences were found between hair shaft sites, supporting a model of the hair shaft as “alive” and responsive to environmental demand in terms of cortisol production. Hair taken from forearms had significantly higher concentrations of cortisol than hair from lower legs, suggesting a localized hair cortisol response and verifying previous findings. Issues of the link between central and peripheral HPA axes are raised for discussion and further investigation.

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