title: Variation in vervet (Chlorocebus aethiops) hair cortisol concentrations reflects ecological disturbance by humans.
abstract: Vervet monkeys (Chlorocebus aethiops) often live in close proximity to humans. Vervets are known to raid crops, homes and gardens in suburban areas leading to human-vervet conflict. In general, primate groups with access to human foods experience increased population densities and intra-group aggression. This suggests high stress loads for vervets living in environments with high levels of human habitat disturbance and close proximity to humans. We tested the hypothesis that populations characterized by high levels of human impact are more physiologically stressed than low human impact populations, and that this increased stress would be reflected in higher concentrations of hair cortisol. We predicted that because females would be less likely to engage in high risk foraging activities, and hence keep more distance from humans than males, their hair cortisol levels should be lower than those in males. We quantified cortisol in the hair of wild caught individuals from populations that experienced different degrees of human habitat disturbance and differences in access to human food. We found that males in high human impact groups had significantly higher hair cortisol concentrations than those in low human impact groups, although this difference was not observed in female vervets. Human impacts on vervet behavioral ecology appear to be a significant source of stress for male animals in particular.
authors: Biobehavioral Branch, Division of Intramural Research, National Institute of Nursing Research, National Institutes of Health, Room 2N104, 10 Center Drive, Bethesda, MD, 20892, USA. fourienh@mail.nih.gov.
authors: Nicolaas H
authors: NH
authors: Fourie
authors: Department of Anthropology, University of Wisconsin-Milwaukee, Milwaukee, WI, 53201, USA.|Department of Genetics, University of the Free State, PO Box 339, Bloemfontein, 9300, South Africa.
authors: Trudy R
authors: TR
authors: Turner
authors: Smithsonian Conservation Biology Institute, Center for Species Survival, Front Royal, VA, 22630, USA.
authors: Janine L
authors: JL
authors: Brown
authors: Department of Evolutionary Anthropology, Duke University, Durham, NC, 27708, USA.
authors: James D
authors: JD
authors: Pampush
authors: Department of Anthropology and Museum Studies, Central Washington University, Ellensburg, WA, 98926, USA.
authors: Joseph G
authors: JG
authors: Lorenz
authors: Department of Anthropology, University of Colorado Boulder, Boulder, CO, 80309, USA.
authors: Robin M
authors: RM
authors: Bernstein
mesh_terms: D000374:Aggression; D000818:Animals; D002522:Chlorocebus aethiops / Q000502:physiology*; D004032:Diet; D005260:Female; D006197:Hair / Q000737:chemistry; D006801:Humans; D006854:Hydrocortisone / Q000378:metabolism*; D008297:Male; D011156:Population Density; D012737:Sex Factors; D013312:Stress, Physiological
chemical_list: D006854:Hydrocortisone
keywords: Cortisol; Hair; Human food; Human impact; Stress; Vervets