Effects of tourist pressure and reproduction on physiological stress response in wildcats: management implications for species conservation
Ana Piñeiro A , Isabel Barja A C , Gema Silván B and Juan Carlos Illera B
+ Author Affiliations
- Author Affiliations
A Departamento de Biología, Unidad de Zoología, Facultad de Ciencias, Universidad Autónoma de Madrid, Spain.
B Departamento de Fisiología (Fisiología Animal), Facultad de Veterinaria, Universidad Complutense de Madrid, Spain.
C Corresponding author. Email: isabel.barja@uam.es
Wildlife Research 39(6) 532-539 https://doi.org/10.1071/WR10218
Submitted: 29 November 2012 Accepted: 12 June 2012 Published: 1 August 2012
Abstract
Context: Ecotourism and human recreational activities are increasing and can have a significant impact on fauna. The analysis of faecal glucocorticoid concentrations is a non-invasive method of measuring physiological stress responses of wildlife to various factors (i.e. human disturbances).
Aims: The aim of the present study was to determine whether increased physiological stress levels in wildcats (Felis silvestris) were a response to the level of tourism allowed within different zones in a natural park and/or a response to the seasonal reproductive state of wildcats.
Methods: The study was conducted from May 2005 to June 2009 at the Natural Park Montes do Invernadeiro (north-western Spain). The Natural Park is divided into the following three zones according to the level of tourism allowed: restricted public-use, restricted zone and integral reserve. An enzyme immunoassay technique was used to quantify cortisol metabolites and sex hormones from each of 110 fresh wildcat faecal samples collected from walked transects on forest roads within each zone. The number of visitors was recorded as a measure of tourist pressure.
Key results: The general linear model indicated that park zone and faecal progesterone levels were the factors that explained the variation in the faecal glucocorticoid metabolite levels. Cortisol metabolite concentrations were higher in some park zones where tourism intensity was higher (restricted public-use zone). Faecal cortisol metabolite concentrations were more elevated during gestation (spring) and during the young dispersal period (autumn).
Key conclusions: Therefore, we recommend that some zones of park (integral reserve) continue being maintained free of visitor impact and that visitor numbers be specially controlled during the animals’ sensitive periods (gestation) in the zone of restricted public use and in the restricted zone.
References
Alcock, J. (Ed.) (1998). ‘Animal Behavior: an Evolutionary Approach.’ (Sinauer: Sunderland, MA.)Arck, P. C., Merali, F. S., Stanisz, A. M., Stead, R. H., Chaouat, G., and Manuel, J. (1995). Stress-induced murine abortion associated with substance P-dependent alteration in cytokines in maternal uterine decidua. Biology of Reproduction 53, 814–819.
| Stress-induced murine abortion associated with substance P-dependent alteration in cytokines in maternal uterine decidua.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK2MXotFyju74%3D&md5=edbe33bfc475dfa5b7a240e84a3c2c65CAS |
Balmford, A., Beresford, J., Green, J., Naidoo, R., Walpole, M., and Manica, A. (2009). A global perspective on trends in nature-based tourism. PLoS Biology 7, e1000144.
| A global perspective on trends in nature-based tourism.Crossref | GoogleScholarGoogle Scholar |
Barja, I. (2005). Winter distribution of European pine marten (Martes martes) scats in a protected area of Galicia, Spain. Mammalia 69, 435–438.
| Winter distribution of European pine marten (Martes martes) scats in a protected area of Galicia, Spain.Crossref | GoogleScholarGoogle Scholar |
Barja, I., and Bárcena, F. (2005). Distribución y abundancia de gato montés (Felis silvestris) en el Parque Natural Os Montes do Invernadeiro (Galicia, NO de España): factores de hábitat implicados y relación con la presencia de zorro y marta. Galemys 17, 29–40.
Barja, I., Silván, G., Rosellini, S., Piñeiro, A., González-Gil, A., Camacho, L., and Illera, J. C. (2007). Stress physiological responses to tourist pressure in a wild population of European pine marten. The Journal of Steroid Biochemistry and Molecular Biology 104, 136–142.
| Stress physiological responses to tourist pressure in a wild population of European pine marten.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2sXmsFKns7g%3D&md5=78a463e46363b5e1596a793ac0f9c470CAS |
Barja, I., Silván, G., Rosellini, S., Piñeiro, A., Illera, M. J., and Illera, J. C. (2008a). Quantification of sexual steroid hormones in faeces of Iberian wolf (Canis lupus signatus): a non-invasive sex typing method. Reproduction in Domestic Animals 43, 701–707.
| Quantification of sexual steroid hormones in faeces of Iberian wolf (Canis lupus signatus): a non-invasive sex typing method.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1MXlvVejug%3D%3D&md5=7226d21f4c23e1017ad4a470e0dbce27CAS |
Barja, I., Silván, G., and Illera, J. C. (2008b). Relationships between sexual and stress hormone levels in feces and marking behavior in a wild population of Iberian wolves (Canis lupus signatus). Journal of Chemical Ecology 34, 697–701.
| Relationships between sexual and stress hormone levels in feces and marking behavior in a wild population of Iberian wolves (Canis lupus signatus).Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1cXnt1aksLY%3D&md5=18bbace71e4f83f0ae802083c5ed4586CAS |
Barja, I., Silván, G., Martínez-Fernández, L., and Illera, J. C. (2011). Physiological stress responses, faecal marking behaviour, and reproduction in wild European pine martens (Martes martes). Journal of Chemical Ecology 37, 253–259.
| Physiological stress responses, faecal marking behaviour, and reproduction in wild European pine martens (Martes martes).Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3MXjvVWmu7Y%3D&md5=c55f61d87298fb6fd7caed800e9b4209CAS |
Belkhir, K., Borsout, P., Goudet, J., Chikhi, L., and Bonhomme, F. (Eds) (1996–2004). ‘Genetix, Logiciel sous WindowsTM pour la Génétique des Populations,’ (Laboratoire Génome et Population, Université de Montpellier: Montepellier, France.)
Benton, T. G., Vickery, J. A., and Wilson, J. D. (2003). Farmland biodiversity: is habitat heterogeneity the key? Trends in Ecology & Evolution 18, 182–188.
| Farmland biodiversity: is habitat heterogeneity the key?Crossref | GoogleScholarGoogle Scholar |
Bonier, F., Quigley, H., and Austad, S. N. (2004). A technique for non-invasively detecting stress response in cougars. Wildlife Society Bulletin 32, 711–717.
| A technique for non-invasively detecting stress response in cougars.Crossref | GoogleScholarGoogle Scholar |
Brown, J. L., and Wildt, D. E. (1997). Assessing reproductive status in wild felids by non-invasive faecal steroid monitoring. International Zoo Yearbook 35, 173–191.
| Assessing reproductive status in wild felids by non-invasive faecal steroid monitoring.Crossref | GoogleScholarGoogle Scholar |
Brown, J. L., Wasser, S. K., Wildt, D. E., and Graham, L. H. (1994). Comparative aspects of steroid hormone metabolism and ovarian activity in felids, measured non invasively in feces. Biology of Reproduction 51, 776–786.
| Comparative aspects of steroid hormone metabolism and ovarian activity in felids, measured non invasively in feces.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK2cXlvFKhu7g%3D&md5=40596eed95e12f330da648959a4c534cCAS |
Brown, J. L., Wildt, D. E., Wielebnowski, N., Goodrowe, K. L., Graham, L. H., Wells, S., and Howard, J. G. (1996). Reproductive activity in captive female cheetahs (Acinonyx jubatus) assessed by faecal steroids. Journal of Reproduction and Fertility 106, 337–346.
| Reproductive activity in captive female cheetahs (Acinonyx jubatus) assessed by faecal steroids.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK28XitFKnt7o%3D&md5=27313fde932311a9f2ab901402ff28fcCAS |
Burnham, K. P., and Anderson, D. R. (2002). ‘Model Selection and Multimodel Inference. A Practical Information-theoretic Approach.’ 2nd edn. (Springer: New York.)
Busch, D. S., and Hayward, L. S. (2009). Stress in a conservation context: a discussion of glucocorticoid actions and how levels change with conservation-relevant variables. Biological Conservation 142, 2844–2853.
| Stress in a conservation context: a discussion of glucocorticoid actions and how levels change with conservation-relevant variables.Crossref | GoogleScholarGoogle Scholar |
Carlstead, K., and Shepherdson, D. (1994). Effects of environmental enrichment on reproduction. Zoo Biology 13, 447–458.
| Effects of environmental enrichment on reproduction.Crossref | GoogleScholarGoogle Scholar |
Corbett, L. K. (1979). Feeding ecology and social organization of wildcats (Felis silvestris) and domestics cats (Felis catus) in Scotland. Ph.D. Thesis, University of Aberdeen, Scotland.
Creel, S., Fox, J. E., Hardy, A., Sands, J., Garrott, B., and Peterson, R. O. (2002). Snowmobile activity and glucocorticoid stress responses in wolves and elk. Conservation Biology 16, 809–814.
| Snowmobile activity and glucocorticoid stress responses in wolves and elk.Crossref | GoogleScholarGoogle Scholar |
Dehnhard, M., Clauss, M., Lechner-Doll, M., Meyer, H. H. D., and Palme, R. (2001). Noninvasive monitoring of adrenocortical activity in roe deer (Capreolus capreolus) by measurement of faecal cortisol metabolites. General and Comparative Endocrinology 123, 111–120.
| Noninvasive monitoring of adrenocortical activity in roe deer (Capreolus capreolus) by measurement of faecal cortisol metabolites.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD3MXlvFSitrs%3D&md5=661dfbba89b75e506c9a5b07af216138CAS |
Eggermann, J. (2009). The impact of habitat fragmentation by anthropogenic infraestructures on wolves (Canis lupus). Ph.D. Thesis, University of Bochum, Germany.
Gagliuso, R. A. (1992). Habitat alteration and human disturbance: their impact on cougar habitat utilization in Southwest Oregon. Ph.D. Thesis, University of Oregon, Corvallis, OR, USA.
Graham, L. H., and Brown, J. L. (1996). Cortisol metabolism in the domestic cat and implications for non-invasive monitoring of adrenocortical function in endangered felids. Zoo Biology 15, 71–82.
| Cortisol metabolism in the domestic cat and implications for non-invasive monitoring of adrenocortical function in endangered felids.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK28Xit1yhtLs%3D&md5=167ace2a81cfe4a906b1312e67ee6935CAS |
Graham, L. H., Goodrowe, K. L., Raeside, J. I., and Liptrap, R. M. (1995). Non-invasive monitoring of ovarian function in several felid species by measurement of faecal estradiol-17β and progestins. Zoo Biology 14, 223–237.
| Non-invasive monitoring of ovarian function in several felid species by measurement of faecal estradiol-17β and progestins.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK2MXnt1OqsL8%3D&md5=06c9ca24d402eccad825b399ed10781eCAS |
Greenberg, N., Carr, J. A., and Summers, C. H. (2002). Causes and consequences of stress. Integrative and Comparative Biology 42, 508–516.
| Causes and consequences of stress.Crossref | GoogleScholarGoogle Scholar |
IUCN (2011). ‘IUCN Red List of Threatened Species. Version 2011.2.’ Available at www.iucnredlist.org [verified 27 November 2011].
Jerosch, S., Götz, M., Klar, N., and Roth, M. (2010). Characteristics of diurnal resting sites of the endangered European wildcat (Felis silvestris silvestris): Implications for its conservation. Journal for Nature Conservation 18, 45–54.
| Characteristics of diurnal resting sites of the endangered European wildcat (Felis silvestris silvestris): Implications for its conservation.Crossref | GoogleScholarGoogle Scholar |
Jurke, M. H., Czekala, N. M., Lindburg, D. G., and Millard, S. E. (1997). Faecal corticoid metabolite measurement in the cheetah (Acinonyx jubatus). Zoo Biology 16, 133–147.
| Faecal corticoid metabolite measurement in the cheetah (Acinonyx jubatus).Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK2sXjtVKhtbc%3D&md5=d9f68cc713014e60b088a9136af362f7CAS |
Kerley, L. L., Goodrich, J. M., Miquelle, D. G., Smirnov, E. N., Quigley, H. B., and Hornocker, M. G. (2002). Effects of roads and human disturbance on Amur tigers. Conservation Biology 16, 97–108.
| Effects of roads and human disturbance on Amur tigers.Crossref | GoogleScholarGoogle Scholar |
Kitchener, A. (Ed.) (1995). ‘The Wildcat.’ (The Mammal Society: London.)
Klar, N., Fernández, N., Kramer-Schadt, S., Herrmann, M., Trinzenf, M., Büttner, I., and Niemitz, C. (2008). Habitat selection models for European wildcat conservation. Biological Conservation 141, 308–319.
| Habitat selection models for European wildcat conservation.Crossref | GoogleScholarGoogle Scholar |
Liu, J., Chen, Y., Guo, L., Gu, B., Liu, H., Hou, A., Liu, X., Sun, L., and Liu, D. (2006). Stereotypic behavior and faecal cortisol level in captive giant pandas in relation to environmental enrichment. Zoo Biology 25, 445–459.
| Stereotypic behavior and faecal cortisol level in captive giant pandas in relation to environmental enrichment.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2sXls1GjtA%3D%3D&md5=8817289681897988e5d105b9b6bfff65CAS |
Mellen, J. (Ed.) (2002). ‘Husbandry Standards for Keeping Small Cats in Captivity.’ (American Zoo and Aquarium Association: Silver Spring, MD.)
Millspaugh, J. J., and Washburn, B. E. (2003). Within-sample variation of fecal glucocorticoid measurements. General and Comparative Endocrinology 132, 21–26.
| Within-sample variation of fecal glucocorticoid measurements.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD3sXjvFWms7k%3D&md5=11b8d89df403530049119d85ca2516a3CAS |
Moberg, G. P. (Ed.) (1985). ‘Animal Stress.’ (American Physiological Society: Bethesda, MD.)
Monfort, S. L., Mashburn, K. L., Brewer, B. A., and Creel, S. R. (1998). Evaluating adrenal activity in African wild dogs (Lycaon pictus) by faecal corticosteroid analysis. Journal of Zoo and Wildlife Medicine 29, 129–133.
| 1:STN:280:DyaK1cvgtVOktg%3D%3D&md5=6b32b73c08213c2b8e3c829e6db7769dCAS |
Montanha, J. C., Silva, S. L., and Boere, V. (2009). Comparison of salivary cortisol concentrations in jaguars kept in captivity with differences in exposure to the public. Ciência Rural 39, 1745–1751.
| Comparison of salivary cortisol concentrations in jaguars kept in captivity with differences in exposure to the public.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1MXhsFyntbnM&md5=46f810f6570095a50b5b72059bd72b01CAS |
Monterroso, P., Brito, J. C., Ferreras, P., and Alves, P. C. (2009). Spatial ecology of the European wildcat in a Mediterranean ecosystem: dealing with small radio-tracking datasets in species conservation. Journal of Zoology 279, 27–35.
| Spatial ecology of the European wildcat in a Mediterranean ecosystem: dealing with small radio-tracking datasets in species conservation.Crossref | GoogleScholarGoogle Scholar |
Möstl, E., and Palme, R. (2002). Hormones as indicators of stress. Domestic Animal Endocrinology 23, 67–74.
| Hormones as indicators of stress.Crossref | GoogleScholarGoogle Scholar |
Müllner, A., Linsenmair, K. E., and Wikelski, M. (2004). Exposure to ecotourism reduces survival and affects stress response in hoatzin chicks (Opisthocomus hoazin). Biological Conservation 118, 549–558.
| Exposure to ecotourism reduces survival and affects stress response in hoatzin chicks (Opisthocomus hoazin).Crossref | GoogleScholarGoogle Scholar |
Nepomnaschy, P. A., Welch, K. B., McConnell, D. S., Low, B. S., Strassman, B. I., and England, B. G. (2006). Cortisol levels and very early pregnancy loss in humans. Proceedings of the National Academy of Sciences, USA 103, 3938–3942.
| Cortisol levels and very early pregnancy loss in humans.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD28XivFWitro%3D&md5=e56d3c17629ec368b95ac502ea624b2eCAS |
Ngoprasert, D., Lynam, A. J., and Gale, G. A. (2007). Human disturbance affects habitat use and behaviour of Asiatic leopard Panthera pardus in Kaeng Krachan National Park, Thailand. Oryx 41, 343–351.
| Human disturbance affects habitat use and behaviour of Asiatic leopard Panthera pardus in Kaeng Krachan National Park, Thailand.Crossref | GoogleScholarGoogle Scholar |
Nowell, K., and Jackson, P. (Eds) (1996). ‘The Wild Cats: Status Survey and Conservation Action Plan.’ (IUCN/Cat Specialist Group: Gland, Switzerland.)
Oliveira, R., Godinho, R., Randi, E., and Alves, P. C. (2008). Hybridization versus conservation: are domestic cats threatening the genetic integrity of wildcats (Felis silvestris silvestris) in Iberian Peninsula? Philosophical Transactions of the Royal Society of London. B 363, 2953–2961.
| Hybridization versus conservation: are domestic cats threatening the genetic integrity of wildcats (Felis silvestris silvestris) in Iberian Peninsula?Crossref | GoogleScholarGoogle Scholar |
Parmesan, C. (2006). Ecological and evolutionary responses to recent climate change. Annual Review of Ecology Evolution and Systematics 37, 637–669.
| Ecological and evolutionary responses to recent climate change.Crossref | GoogleScholarGoogle Scholar |
Pierce, B. N., Hemsworth, P. H., Rivalland, E. T. A., Wagenmaker, E. R., Morrissey, A. D., Papargiris, M. M., Clarke, I. J., Karsch, F. J., Turner, A. I., and Tilbrook, A. J. (2008). Psychosocial stress suppresses attractivity, proceptivity and pulsatile LH secretion in the ewe. Hormones and Behavior 54, 424–434.
| Psychosocial stress suppresses attractivity, proceptivity and pulsatile LH secretion in the ewe.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1cXptVajurg%3D&md5=2fe2271376d97da496835ffadf240a71CAS |
Pulgar, I. (Ed.) (2004). ‘Guía da flora do Parque Natural Montes do Invernadeiro.’ (Consellería de Medio Ambiente, Xunta de Galicia: Ourense, Spain.)
Randi, E., Pierpaoli, M., Beaumont, M., Ragni, B., and Sforzi, A. (2001). Genetic identification of wild and domestic cats (Felis silvestris) and their hybrids using bayesian clustering methods. Molecular Biology and Evolution 18, 1679–1693.
| Genetic identification of wild and domestic cats (Felis silvestris) and their hybrids using bayesian clustering methods.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD3MXmt12iu7o%3D&md5=77299634f5850073704175b222bd1170CAS |
Sambrook, E., Fritsch, F., and Maniatis, T. (Eds) (1989). ‘Molecular Cloning.’ (Cold Spring Harbour Press: New York.)
Sapolsky, R. M. (1986). Stress-induced elevation of testosterone concentrations in high-ranking baboons: role of catecholamines. Endocrinology 118, 1630–1635.
| Stress-induced elevation of testosterone concentrations in high-ranking baboons: role of catecholamines.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaL28XitVSntb0%3D&md5=afb0ca435d7c4c2bc4173ff8410708c2CAS |
Sapolsky, R. M. (1992). Neuroendocrinology of the stress response. In ‘Behavioral Endocrinology’. (Eds J. B. Becker, S. M. Breedlove and D. Crews.) pp. 287–324. (MIT Press: Cambridge, UK.)
Sapolsky, R. M., Romero, L. M., and Munck, A. U. (2000). How do glucocorticoids influence stress responses? Integrating permissive, suppressive, stimulatory, and preparative actions. Endocrine Reviews 21, 55–89.
| How do glucocorticoids influence stress responses? Integrating permissive, suppressive, stimulatory, and preparative actions.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD3cXhs12hu78%3D&md5=5374d49bd368843ebf89c240ee1dce49CAS |
Schwarzenberger, F., Walzer, C., Weiss, R., Pucher, H. E., Leus, K., Bircher, P., and Moran, J. F. (2000). Faecal cortisol metabolites in response to management practices and disturbance in different herbivores and carnivores (Ceratotherium simum, Diceros bicornis, Elephas maximus, Loxodonta africana, Okapia johnstoni, Rupicapra rupicapra and Lutra lutra). In ‘Proceedings of the European Association of Zoo and Wildlife Veterinarians (EAZWV), Third Scientific Meeting’. (Ed. P. Zwart.) pp. 1–4. (Paris Zoo: Paris.)
Shepherd, B., and Whittington, J. (2006). Response of wolves to corridor restoration and human use management. Ecology and Society 11, 1–15.
Shille, V. M., Haggerty, M. A., Shackleton, C., and Lasley, B. L. (1990). Metabolites of estradiol in serum, bile, intestine and feces of the domestic cat. Theriogenology 34, 779–794.
| Metabolites of estradiol in serum, bile, intestine and feces of the domestic cat.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK3MXksVaitbY%3D&md5=a460bceb00212fc71b35588bd21070f8CAS |
Stahl, P., and Artois, M. (Eds.) (1991). ‘Status and Conservation of the Wildcat (Felis silvestris) in Europe and around the Mediterranean Rim.’ (Council of Europe: Strasbourg.)
Stahl, P., and Leger, F. (1992). Le chat sauvage (Felis silvestris, Schreber, 1777). In ‘Encyclopédie des Carnivores de France’. (Ed. M. Artois and H. Maurin.) pp. 1–50. (Société Française pour l’Etude et la Protection des Mammifères (S.F.E.P.M.): Bohallard, Puceul.)
Sunquist, M., and Sunquist, F. (Eds) (2002). ‘Wild Cats of the World.’ (The University of Chicago Press: Chicago, IL.)
Terio, K. A., Marker, L., and Munson, L. (2004). Evidence for chronic stress in captive but not free-ranging cheetahs (Acinonyx jubatus) based on adrenal morphology and function. Journal of Wildlife Diseases 40, 259–266.
| 1:CAS:528:DC%2BD2cXmsVShurs%3D&md5=b59b268da693569f3f071be10fa8758cCAS |
Theuerkauf, J., Gula, R., Pirga, B., Tsunoda, H., Eggermann, J., Brzezowska, B., Rouys, S., and Radler, S. (2007). Human impact on wolf activity in the Bieszczady Mountains, SE Poland. Annales Zoologici Fennici 44, 225–231.
Thiel, D., Jenni-Eiermann, S., Braunisch, V., Palme, R., and Jenni, L. (2008). Ski tourism affects habitat use and evokes a physiological stress response in capercaillie Tetrao urogallus: a new methodological approach. Journal of Applied Ecology 45, 845–853.
| Ski tourism affects habitat use and evokes a physiological stress response in capercaillie Tetrao urogallus: a new methodological approach.Crossref | GoogleScholarGoogle Scholar |
Thomas, C. D., Cameron, A., and Green, R. E. (2004). Extinction risk from climate change. Nature 427, 145–148.
| Extinction risk from climate change.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2cXhtFOgtQ%3D%3D&md5=0656cef05bbcdd0c2250af9c0ccb955aCAS |
Tilman, D., Cassman, K. G., Matson, P. A., Naylor, R., and Polasky, S. (2002). Agricultural sustainability and intensive production practices. Nature 418, 671–677.
| Agricultural sustainability and intensive production practices.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD38XlvVyltb0%3D&md5=dafa6ca153534831d2e2f001a64011baCAS |
Touma, C., and Palme, R. (2005). Measuring fecal glucocorticoid metabolites in mammals and birds: the importance of validation. Annals of the New York Academy of Sciences 1046, 54–74.
| Measuring fecal glucocorticoid metabolites in mammals and birds: the importance of validation.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2MXhtVWjtL%2FE&md5=2394aedb3d2b970445e102d3c7939beaCAS |
Van Dyke, F. G., Broche, R. H., Shaw, H. G., Ackerman, B. B., Hemker, T. P., and Lindzey, F. G. (1986). Reactions on mountain lions to logging and human activity. The Journal of Wildlife Management 50, 95–102.
| Reactions on mountain lions to logging and human activity.Crossref | GoogleScholarGoogle Scholar |
Van Meter, P. E., French, J. A., Dloniak, S. M., Watts, H. E., Kolowski, J. M., and Holekamp, K. E. (2009). Fecal glucocorticoids reflect socio-ecological and anthropogenic stressors in the lives of wild spotted hyenas. Hormones and Behavior 55, 329–337.
| Fecal glucocorticoids reflect socio-ecological and anthropogenic stressors in the lives of wild spotted hyenas.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1MXhtlSluro%3D&md5=147dc8ffb2e7e2f30a0a53a3fd795722CAS |
Verhage, H. G., Beamer, N. B., and Brenner, R. M. (1976). Plasma levels of estradiol and progesterone in the cat during polyestrus, pregnancy and pseudopregnancy. Biology of Reproduction 14, 579–585.
| Plasma levels of estradiol and progesterone in the cat during polyestrus, pregnancy and pseudopregnancy.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaE28XkslGrs7o%3D&md5=f00f424b092f152648130b9d603d11fdCAS |
von der Ohe, C. G., Wasser, S. K., Hunt, K. E., and Servheen, C. (2004). Factors associated with fecal glucocorticoids in Alaskan brown bears (Ursus arctos horribilis). Physiological and Biochemical Zoology 77, 313–320.
| Factors associated with fecal glucocorticoids in Alaskan brown bears (Ursus arctos horribilis).Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2cXlslCmsrc%3D&md5=7cbc71bc138ff5e780e3e226d792b02aCAS |
Wielebnowski, N. C., Fletchall, N., Carlstead, K., Busso, J. M., and Brown, J. L. (2002). Noninvasive assessment of adrenal activity associated with husbandry and behavioral factors in the North American clouded leopard population. Zoo Biology 21, 77–98.
| Noninvasive assessment of adrenal activity associated with husbandry and behavioral factors in the North American clouded leopard population.Crossref | GoogleScholarGoogle Scholar |
Young, K. M., Walker, S. L., Lanthier, C., Waddell, W. T., Monfort, S. L., and Brown, J. L. (2004). Noninvasive monitoring of adrenocortical activity in carnivores by faecal glucocorticoid analyses. General and Comparative Endocrinology 137, 148–165.
| Noninvasive monitoring of adrenocortical activity in carnivores by faecal glucocorticoid analyses.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2cXkt1ajsr8%3D&md5=9b5f90e20fff9fae0c5cb900b16ab927CAS |
