TY - JOUR
T1 - Fecal glucocorticoid assays and the physiological stress response in elk
AU - Millspaugh, J. J.
AU - Woods, R. J.
AU - Hunt, K. E.
AU - Raedeke, K. J.
AU - Brundige, G. C.
AU - Washburn, B. E.
AU - Wasser, S. K.
PY - 2001
Y1 - 2001
N2 - Fecal glucocorticoid assays provide a potentially useful, noninvasive means to study physiological responses of wildlife to various stressors. Consequently we quantified fecal glucocorticoid concentrations among free-ranging elk (Cervus elaphus) by subherd, sex, and season and determined their relationship to various human activities and environmental conditions. Using a validated technique, we assayed 558 fecal samples collected from 30 radiocollared elk in the Black Hills, South Dakota, from June 1995 to September 1997. Fecal glucocorticoid measures were least in winter (x̄=17.41 ng/g, SE=2.97 for bull subherds and 18.9 ng/g, SE=2.85 for cow subherds) and increased to peak concentrations in summer (x̄=33.6 ng/g, SE=3.42 for bull subherds and 34.21 ng/g, SE=3.71 for cow subherds). Vehicle use along primary roads, primary road density, and mean temperature each independently explained a significant portion of the variation in fecal glucocorticoid concentrations (r2=0.61, F2,557=286.13, P<0.001). Annual glucocorticoid secretion also may be related to normal seasonal metabolic rhythms. Though more research is needed on fecal glucocorticoid concentrations of undisturbed elk, we hypothesize that human activities, high temperatures, or normal seasonal metabolic rhythms may have elevated summer glucocorticoid concentrations. Our findings suggested that fecal glucocorticoid assays, if coupled with population performance measures, could assess physiological effects of natural and human-induced disturbances on free-ranging elk. Also, our study illustrated the need for caution when interpreting fecal glucocorticoid measurements, because several confounding factors may influence interpretation.
AB - Fecal glucocorticoid assays provide a potentially useful, noninvasive means to study physiological responses of wildlife to various stressors. Consequently we quantified fecal glucocorticoid concentrations among free-ranging elk (Cervus elaphus) by subherd, sex, and season and determined their relationship to various human activities and environmental conditions. Using a validated technique, we assayed 558 fecal samples collected from 30 radiocollared elk in the Black Hills, South Dakota, from June 1995 to September 1997. Fecal glucocorticoid measures were least in winter (x̄=17.41 ng/g, SE=2.97 for bull subherds and 18.9 ng/g, SE=2.85 for cow subherds) and increased to peak concentrations in summer (x̄=33.6 ng/g, SE=3.42 for bull subherds and 34.21 ng/g, SE=3.71 for cow subherds). Vehicle use along primary roads, primary road density, and mean temperature each independently explained a significant portion of the variation in fecal glucocorticoid concentrations (r2=0.61, F2,557=286.13, P<0.001). Annual glucocorticoid secretion also may be related to normal seasonal metabolic rhythms. Though more research is needed on fecal glucocorticoid concentrations of undisturbed elk, we hypothesize that human activities, high temperatures, or normal seasonal metabolic rhythms may have elevated summer glucocorticoid concentrations. Our findings suggested that fecal glucocorticoid assays, if coupled with population performance measures, could assess physiological effects of natural and human-induced disturbances on free-ranging elk. Also, our study illustrated the need for caution when interpreting fecal glucocorticoid measurements, because several confounding factors may influence interpretation.
KW - Black Hills
KW - Cervus elaphus
KW - Corticosterone
KW - Elk
KW - Fecal glucocorticoids
KW - Human disturbance
KW - Physiology
KW - South Dakota
KW - Stress
UR - http://www.scopus.com/inward/record.url?scp=0034754983&partnerID=8YFLogxK
M3 - Article
AN - SCOPUS:0034754983
SN - 0091-7648
VL - 29
SP - 899
EP - 907
JO - Wildlife Society Bulletin
JF - Wildlife Society Bulletin
IS - 3
ER -