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Deacon F, Smit GN, Grobbelaar A. Resources and Habitat Requirements for Giraffes' ( Giraffa camelopardalis) Diet Selection in the Northwestern Kalahari, South Africa. Animals (Basel) 2023; 13:2188. [PMID: 37443986 DOI: 10.3390/ani13132188] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Revised: 06/24/2023] [Accepted: 06/28/2023] [Indexed: 07/15/2023] Open
Abstract
Diet selection concerning browse availability of giraffes (Giraffa camelopardalis) was studied over 15 months in an arid environment in South Africa. A global positioning system collar was fitted to a giraffe individual to assess the specific areas, consisting of different vegetation types, that the population utilised during different seasons. Results are provided on diet selection in relation to browse availability between seasons and vegetation types, including tree densities and the amount of the total evapotranspiration tree equivalents. Diet selections of the giraffe population changed in response to the availability of browse material from July to October. The availability of important resource areas had a significant (p < 0.05) effect on the spatial ecology, and an increase in home range size was noted. Information that is important for the well-being of giraffes was identified. This included nutritional stress and the limited variety of the most utilised tree species available for browsing, especially during critical dry periods. The results demonstrate the importance of assessment of giraffes' diet selection in relation to browse availability, especially before introduction to a new area, to limit the lack of population growth and underperformance. This study provides valuable information towards understanding the resources and habitats required for successful giraffe management.
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Affiliation(s)
- Francois Deacon
- Department of Animal Sciences, Faculty of Natural and Agricultural Sciences, University of the Free State, P.O. Box 339, Bloemfontein 9300, South Africa
| | - Gert Nicolaas Smit
- Department of Animal Sciences, Faculty of Natural and Agricultural Sciences, University of the Free State, P.O. Box 339, Bloemfontein 9300, South Africa
| | - Andri Grobbelaar
- Department of Animal Sciences, Faculty of Natural and Agricultural Sciences, University of the Free State, P.O. Box 339, Bloemfontein 9300, South Africa
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2
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Panchal N, Desai C, Ghosal R. Fecal glucocorticoid metabolite levels in captive Indian leopards (Panthera pardus fusca) housed under three different enrichment regimes. PLoS One 2022; 17:e0261796. [PMID: 36083970 PMCID: PMC9462577 DOI: 10.1371/journal.pone.0261796] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Accepted: 08/24/2022] [Indexed: 11/26/2022] Open
Abstract
Environmental enrichment improves the health and wellbeing of zoo animals. To test this hypothesis, we used Indian leopards (Panthera pardus fusca), one of the popular zoo animals, as a model organism to understand effects of active and passive enrichment elements on stress hormone levels of captive individuals. We included three enrichment categories, category ‘A’ (having both active: cage size of 1204 m3 with raised platforms and earthen flooring, and passive: controlled temperature, playback of forest sounds and sound proof glass to filter visitors’ noise, enrichment elements), category ‘B’ (active enrichment type I, cage size of 264 m3 with air coolers), and category C (active enrichment type II, cage size of 517 m3 without air coolers) for leopards (n = 14) housed in two Indian zoos. We used a group-specific enzyme immunoassay to measure fecal glucocorticoid metabolites (fGCM) in captive leopards. For comparison, we analysed samples from free-ranging leopards, as well. fGCM levels (Mean±SEM) were 10.45±2.01 and 0.95±0.003 μg/g dry feces in captive and free-ranging leopards, respectively. Our results revealed that fGCM levels of leopards in categories B and C were significantly (P<0.05) different from each other, thus, indicating cage size (an active enrichment element) as an important factor in influencing the physiology of the sampled animals. Overall, the findings of the study will contribute towards informed policies for management of captive Indian leopards.
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Affiliation(s)
- Nirali Panchal
- Biological and Life Sciences, School of Arts and Sciences, Ahmedabad University, Ahmedabad, Gujarat, India
| | - Chena Desai
- Biological and Life Sciences, School of Arts and Sciences, Ahmedabad University, Ahmedabad, Gujarat, India
| | - Ratna Ghosal
- Biological and Life Sciences, School of Arts and Sciences, Ahmedabad University, Ahmedabad, Gujarat, India
- * E-mail:
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3
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Using spot pattern recognition to examine population biology, evolutionary ecology, sociality, and movements of giraffes: a 70-year retrospective. Mamm Biol 2022. [DOI: 10.1007/s42991-022-00261-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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4
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Fink LB, Scarlata CD, VanBeek B, Bodner TE, Wielebnowski NC. Applying Behavioral and Physiological Measures to Assess the Relative Impact of the Prolonged COVID-19 Pandemic Closure on Two Mammal Species at the Oregon Zoo: Cheetah ( A. jubatus) and Giraffe ( G. c. reticulata and G. c. tippelskirchii). Animals (Basel) 2021; 11:3526. [PMID: 34944302 PMCID: PMC8698047 DOI: 10.3390/ani11123526] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Revised: 11/26/2021] [Accepted: 11/26/2021] [Indexed: 11/17/2022] Open
Abstract
The effect of visitor presence on zoo animals has been explored in numerous studies over the past two decades. However, the opportunities for observations without visitors have been very limited at most institutions. In 2020, the Oregon Zoo was closed, in response to the global SARS-CoV-2 (COVID-19) pandemic, from 15 March 2020 to 12 July 2020, resulting in approximately four consecutive months without visitor presence. This study aimed to quantify potential behavioral and hormonal changes expressed during two transition periods in zoo visitor attendance: the initial time period before and after closure in March 2020 and time before and after reopening in July 2020. Fecal glucocorticoid metabolite (fGM) concentrations of resident giraffes (n = 2) and cheetahs (n = 2) were tracked using enzyme immunoassay (EIA) analyses. Average fGM concentrations during the two transition periods were compared using a two-way mixed ANOVA. Additionally, twice-weekly scan sampling was used to quantify behavioral observations across the transitions, which were analyzed as individual behavior proportions. Individual behavior proportions were compared across the Zoo's opening status and time of day using Kruskal-Wallis (H) tests. The results of our analyses showed the following outcomes: (1) significant increases in fGM concentrations for cheetahs and giraffes between the transition periods but not within them; (2) a significant increase in time spent 'not visible' in the cheetahs in the second transition period; and (3) increased vigilance behaviors in the giraffes immediately after the Zoo's closure. However, the changes observed in fGM concentrations may be more strongly correlated with concomitant social changes (giraffes) and some medical events (cheetahs) rather than with the Zoo's opening status. Nevertheless, this study was able to quantify differences in behavioral frequencies and fGM concentration in cheetahs and giraffes at the Oregon Zoo during the times of transition between visitor's presence and absence. The results indicate that, while there was a possible, but relatively minor impact of the presence and absence of visitors on some behaviors, the differences observed in fGM concentration may have been more affected by some of the concomitant social changes and medical events that happened during the same period than by the presence or absence of visitors.
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Affiliation(s)
- Laurel B. Fink
- Department of Biology, Portland State University, 1719 SW 10th Avenue, SRTC rm 246, Portland, OR 97201, USA
- Oregon Zoo, 4001 SW Canyon Rd, Portland, OR 97221, USA; (C.D.S.); (B.V.); (N.C.W.)
| | - Candace D. Scarlata
- Oregon Zoo, 4001 SW Canyon Rd, Portland, OR 97221, USA; (C.D.S.); (B.V.); (N.C.W.)
| | - Becca VanBeek
- Oregon Zoo, 4001 SW Canyon Rd, Portland, OR 97221, USA; (C.D.S.); (B.V.); (N.C.W.)
| | - Todd E. Bodner
- Department of Psychology, Portland State University, 1721 SW Broadway, Cramer Hall rm 317, Portland, OR 97201, USA;
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5
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Abstract
Dispersal is a critical process that shapes the structure of wild animal populations. In species that form multi‐level societies, natal dispersal might be social (associating with a different social community while remaining near the natal area), spatial (moving away from the natal area while continuing to associate with the same community) or both social and spatial (associating with a different community and moving away from the natal area). For such species, classical spatial measures of dispersal, such as distance moved, might not capture social dispersal. We examined dispersal outcomes for 67 male and 70 female giraffe calves over 7 years in a large, unfenced, ecologically heterogeneous landscape. We tested predictions about the influence of sex, food availability, low‐ and high‐impact human settlements, and local giraffe population density on social or spatial dispersal, dispersal distance, and age of dispersal. We found that dispersal is sex‐specific, with females being predominately philopatric. When dispersing, both sexes did so at a mean of 4 years of age. Most (69% of total) young males dispersed, with 84% of male dispersers associating with a different adult female social community than that of their mother, but one in four of these dispersers remained spatially near to their natal area. For adolescent males that dispersed socially but not spatially, overlapping female social communities may represent a potential pool of unrelated mating partners without the risks of travelling to unfamiliar areas. Just 26% of young females dispersed and half of these continued to associate with the adult female social community into which they were born, confirming the importance of maintaining ties among females from calf to adulthood. Furthermore, individuals born farther from high‐impact human settlements were more likely to spatially or socially‐and‐spatially disperse, move greater distances from their natal areas, and disperse at a younger age. Our study highlights the potential importance of social structure in dispersal decisions, and of tracking social structure when studying dispersal in multi‐level societies, as effective dispersal can be attained without large‐scale spatial displacements.
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Affiliation(s)
- Luca Börger
- Department of Biosciences, Swansea University, Swansea, UK
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6
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Granweiler J, Thorley J, Rotics S. Sparring dynamics and individual laterality in male South African giraffes. Ethology 2021. [DOI: 10.1111/eth.13199] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Affiliation(s)
- Jessica Granweiler
- School of Earth and Environmental Sciences University of Manchester Manchester UK
| | - Jack Thorley
- Department of Zoology University of Cambridge Cambridge UK
- Department of Earth, Oceans and Ecological Sciences University of Liverpool Liverpool UK
| | - Shay Rotics
- Department of Zoology University of Cambridge Cambridge UK
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Anthropogenic Influences on Distance Traveled and Vigilance Behavior and Stress-Related Endocrine Correlates in Free-Roaming Giraffes. Animals (Basel) 2021; 11:ani11051239. [PMID: 33923117 PMCID: PMC8145588 DOI: 10.3390/ani11051239] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Revised: 04/16/2021] [Accepted: 04/19/2021] [Indexed: 11/17/2022] Open
Abstract
Simple Summary Change in an animal’s behavior due to anthropogenic influences is often expressed in a change in movement patterns and increased vigilance and can result in the secretion of stress-related hormones. However, animals can get habituated to human presence after repeated stimulation. We aimed to obtain a first insight into the effect of human observers on the behavior and stress-related hormone concentrations of free-roaming giraffes as well as their habituation process. Giraffes walked further distances and had elevated fecal glucocorticoid metabolite (fGCM) concentration (stress hormone) in the presence of humans, but anthropogenic influences on their distance walked and fGCM concentration decreased with the increase of habituation. The giraffes were vigilant towards human observers; however, the percentage of time spent on observing a human observer did not decrease with the increase of habituation. Abstract Giraffes are an important tourist attraction, and human presence to wildlife is increasing. This has an impact on an animal’s behavior and its endocrine correlates. Studies on other species show alterations in movement patterns, vigilance, and stress-related hormone levels in the presence of humans. Limited information is available on how anthropogenic activities alter giraffe’s behavior, social structure, and related endocrine parameters. The purpose of this study was to obtain insight into anthropogenic influences on giraffe’s behavior and adrenal activity. We used GPS devices mounted onto giraffes to compare the distance walked in the presence or absence of human observers. We also conducted behavioral observations to assess their vigilance and collected fecal samples to analyze their fecal glucocorticoid metabolite (fGCM) concentrations. Giraffes walked significantly further distances in the presence of humans, but the cumulative time that observers were present decreased the hourly distance walked with an observer present, suggesting that the giraffes were becoming habituated. The number of observers present significantly increased the percentage of time spent on observing an observer as well as the number of unhabituated individuals present in the herd. The percentage of time spent observing a human observer did not decrease with the increase of habituation. Last, fGCM concentrations increased with human presence but decreased when individuals became habituated to human presence. More research is needed to understand the effect of anthropogenic influences in different scenarios (e.g., tourism, vehicles, hunting, etc.).
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Scheijen CPJ, Bercovitch FB, Luther‐Binoir I, Ganswindt A, Deacon F. Sexual selection and endocrine profiles in wild South African giraffe (
Giraffa camelopardalis
giraffa
). Afr J Ecol 2020. [DOI: 10.1111/aje.12802] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Ciska P. J. Scheijen
- Animal, Wildlife and Grassland Sciences University of the Free State Bloemfontein South Africa
- Rockwood Conservation Fund NPO Griekwastad South Africa
| | - Fred B. Bercovitch
- Animal, Wildlife and Grassland Sciences University of the Free State Bloemfontein South Africa
- Save the Giraffes San Antonia TX USA
- Wildlife Research Center Kyoto University Kyoto Japan
| | - Ilse Luther‐Binoir
- GEOsperm, Wildlife Reproduction and Biotechnology Services Brits South Africa
- Profetura, Alliance for Wildlife Conservation Breeding Hamburg Germany
| | - Andre Ganswindt
- Department of Zoology and Entomology Mammal Research InstituteUniversity of Pretoria Hatfield South Africa
- Endocrine Research Laboratory Department of Anatomy and Physiology University of Pretoria Onderstepoort South Africa
- Centre for Veterinary Wildlife Studies University of Pretoria Onderstepoort South Africa
| | - Francois Deacon
- Animal, Wildlife and Grassland Sciences University of the Free State Bloemfontein South Africa
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9
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Majelantle TL, McIntyre T, Ganswindt A. Monitoring the effects of land transformation on African clawless otters (Aonyx capensis) using fecal glucocorticoid metabolite concentrations as a measure of stress. Integr Zool 2020; 15:293-306. [PMID: 31912606 DOI: 10.1111/1749-4877.12428] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
In a time of increasing environmental change caused by anthropogenic disturbance, there is a greater need to understand animal adaptations to manmade environments. In this regard, the measurement of stress-related endocrine markers provides a useful tool to examine the impact of environmental challenges and the physiological consequences for wildlife occupying such space. The aims of the present study were to validate fecal glucocorticoid metabolite (fGCM) concentrations as a measure of stress using samples from a male African clawless otter (Aonyx capensis; n = 1) and to compare fGCM concentrations of otters occurring in a transformed and in 2 natural areas in South Africa. From the 5 different enzyme-immunoassays (EIA) tested, a cortisol and oxoetiocholanolone (measuring 11,17 dioxoandrostanes) EIA revealed the highest response (74% and 48% increase, respectively) 30 and 24 hours after a stress event (translocation of a captive individual as part of its rehabilitation prior to release), respectively. For both EIAs, fGCM concentrations were comparable for samples collected up to 3 h post-defecation. Using the cortisol EIA for subsequent analyses, fGCM concentrations of animals from the transformed area (n = 20; mean [± SD]: 0.468 [± 0.539] µg/g dry weight [DW]) were significantly higher (P = 0.013) than those from otters in the natural areas (n = 17; 0.242 [± 0.226] µg/g DW). These preliminary results suggest that African clawless otters may have increased adrenocortical activity that could be due to conditions linked to living in a transformed environment.
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Affiliation(s)
- Tshepiso L Majelantle
- Mammal Research Institute, Department of Zoology and Entomology, University of Pretoria, Pretoria, South Africa
| | - Trevor McIntyre
- Mammal Research Institute, Department of Zoology and Entomology, University of Pretoria, Pretoria, South Africa.,Department of Life and Consumer Sciences, University of South Africa, Pretoria, South Africa
| | - Andre Ganswindt
- Mammal Research Institute, Department of Zoology and Entomology, University of Pretoria, Pretoria, South Africa.,Endocrine Research Laboratory, Department of Anatomy and Physiology, University of Pretoria, Onderstepoort, South Africa.,Centre for Veterinary Wildlife Studies, Faculty of Veterinary Science, University of Pretoria, Onderstepoort, South Africa
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10
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Seltmann MW, Ukonaho S, Reichert S, Dos Santos D, Nyein UK, Htut W, Lummaa V. Faecal Glucocorticoid Metabolites and H/L Ratio are Related Markers of Stress in Semi-Captive Asian Timber Elephants. Animals (Basel) 2020; 10:ani10010094. [PMID: 31935980 PMCID: PMC7023510 DOI: 10.3390/ani10010094] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2019] [Revised: 12/21/2019] [Accepted: 01/03/2020] [Indexed: 11/19/2022] Open
Abstract
Simple Summary Animals are kept in captivity for various reasons worldwide. Throughout its range countries, the Asian elephant is used for various purposes, with a significant proportion of the remaining population working as draft and transport animals in the timber industry. However, captivity can also lead to compromises in welfare that need to be quantified for successful intervention. A key way of assessing an animal’s well-being in wildlife and zoo biology is to measure its stress. Previous studies have found positive, negative, or no relationship between two commonly used measures of stress: stress hormones and the ratio of two types of white blood cells—heterophils to lymphocytes. Our study is one of the first to show a positive and consistent link between these two measures in semi-captive Asian elephants from Myanmar, irrespective of sex, age, or environmental context. Our results show that using the heterophil/lymphocyte ratio from blood smears on-site may offer a potentially cheaper and faster way to determine stress than measuring faecal glucocorticoid metabolite concentrations in the laboratory. Abstract Animals are kept in captivity for various reasons, but species with a slower pace of life may adapt to captive environments less easily, leading to welfare concerns and the need to assess stress reliably in order to develop effective interventions. Our aim was to assess welfare of semi-captive timber elephants from Myanmar by investigating the relationship between two physiological markers of stress commonly used as proxies for welfare, faecal glucocorticoid metabolite concentrations (FGM) and heterophil/lymphocyte ratios (H/L), and link these measures to changes in body condition (determined by body weight). We further assessed how robustly these two markers of stress performed in animals of different age or sex, or in different ecological contexts. We measured FGM concentrations and H/L ratios between 2016 and 2018 from 316 samples of 75 females and 49 males ranging in age from 4 to 68. We found a positive and consistent link between FGMs and H/L ratios in Asian elephants, irrespective of their sex, age, or ecological context. Our results will help to inform managers of (semi-) captive elephants about using heterophil/lymphocyte ratio data from blood smears on site as a potentially cheaper and faster alternative to determining stress than measuring faecal glucocorticoid metabolite concentrations in the laboratory.
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Affiliation(s)
- Martin W. Seltmann
- Department of Biology, University of Turku, FIN-20014 Turku, Finland; (S.U.); (S.R.); (D.D.S.); (V.L.)
- Correspondence:
| | - Susanna Ukonaho
- Department of Biology, University of Turku, FIN-20014 Turku, Finland; (S.U.); (S.R.); (D.D.S.); (V.L.)
| | - Sophie Reichert
- Department of Biology, University of Turku, FIN-20014 Turku, Finland; (S.U.); (S.R.); (D.D.S.); (V.L.)
| | - Diogo Dos Santos
- Department of Biology, University of Turku, FIN-20014 Turku, Finland; (S.U.); (S.R.); (D.D.S.); (V.L.)
| | - U Kyaw Nyein
- Myanma Timber Enterprise, Ministry of Natural Resources and Environmental Conservation, Gyogone Forest Compound, Bayint Naung Road, Insein Township, Yangon, Myanmar; (U.K.N.); (W.H.)
| | - Win Htut
- Myanma Timber Enterprise, Ministry of Natural Resources and Environmental Conservation, Gyogone Forest Compound, Bayint Naung Road, Insein Township, Yangon, Myanmar; (U.K.N.); (W.H.)
| | - Virpi Lummaa
- Department of Biology, University of Turku, FIN-20014 Turku, Finland; (S.U.); (S.R.); (D.D.S.); (V.L.)
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11
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Wolf TE, Valades GB, Simelane P, Bennett NC, Ganswindt A. The relationship between physical injury, body condition and stress-related hormone concentrations in free-ranging giraffes. WILDLIFE BIOLOGY 2018. [DOI: 10.2981/wlb.00460] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/01/2022]
Affiliation(s)
- Tanja E. Wolf
- T. E. Wolf (http://orcid.org/0000-0003-4040-8425) , N. C. Bennett and A. Gans
| | | | - Phumlile Simelane
- G. Benavides Valades and P. Simelane, Savannah Research Center, Mbuluzi Game Reserve, Lubombo Conser
| | - Nigel C. Bennett
- T. E. Wolf (http://orcid.org/0000-0003-4040-8425) , N. C. Bennett and A. Gans
| | - Andre Ganswindt
- T. E. Wolf (http://orcid.org/0000-0003-4040-8425) , N. C. Bennett and A. Gans
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12
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Seeber PA, Franz M, Dehnhard M, Ganswindt A, Greenwood AD, East ML. Plains zebra (Equus quagga) adrenocortical activity increases during times of large aggregations in the Serengeti ecosystem. Horm Behav 2018; 102:1-9. [PMID: 29630896 DOI: 10.1016/j.yhbeh.2018.04.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/01/2017] [Revised: 03/19/2018] [Accepted: 04/03/2018] [Indexed: 11/25/2022]
Abstract
Adverse environmental stimuli (stressors) activate the hypothalamic-pituitary-adrenal axis and contribute to allostatic load. This study investigates the contribution of environmental stressors and life history stage to allostatic load in a migratory population of plains zebras (Equus quagga) in the Serengeti ecosystem, in Tanzania, which experiences large local variations in aggregation. We expected higher fGCM response to the environmental stressors of feeding competition, predation pressure and unpredictable social relationships in larger than in smaller aggregations, and in animals at energetically costly life history stages. As the study was conducted during the 2016 El Niño, we did not expect food quality of forage or a lack of water to strongly affect fGCM responses in the dry season. We measured fecal glucocorticoid metabolite (fGCM) concentrations using an enzyme immunoassay (EIA) targeting 11β-hydroxyetiocholanolone and validated its reliability in captive plains zebras. Our results revealed significantly higher fGCM concentrations 1) in large aggregations than in smaller groupings, and 2) in band stallions than in bachelor males. Concentrations of fGCM were not significantly higher in females at the energetically costly life stage of late pregnancy/lactation. The higher allostatic load of stallions associated with females, than bachelor males is likely caused by social stressors. In conclusion, migratory zebras have elevated allostatic loads in large aggregations that probably result from their combined responses to increased feeding competition, predation pressure and various social stressors. Further research is required to disentangle the contribution of these stressors to allostatic load in migratory populations.
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Affiliation(s)
- P A Seeber
- Leibniz-Institute for Zoo and Wildlife Research, Alfred-Kowalke-Strasse 17, 10315 Berlin, Germany
| | - M Franz
- Leibniz-Institute for Zoo and Wildlife Research, Alfred-Kowalke-Strasse 17, 10315 Berlin, Germany
| | - M Dehnhard
- Leibniz-Institute for Zoo and Wildlife Research, Alfred-Kowalke-Strasse 17, 10315 Berlin, Germany
| | - A Ganswindt
- Endocrine Research Laboratory, Department of Anatomy and Physiology, Faculty of Veterinary Science, University of Pretoria, Private Bag XO4, Onderstepoort 0110, South Africa; Mammal Research Institute, Department of Zoology and Entomology, Faculty of Natural and Agricultural Sciences, University of Pretoria, Pretoria 0028, South Africa
| | - A D Greenwood
- Leibniz-Institute for Zoo and Wildlife Research, Alfred-Kowalke-Strasse 17, 10315 Berlin, Germany; Department of Veterinary Medicine, Freie Universität Berlin, Berlin, Germany.
| | - M L East
- Leibniz-Institute for Zoo and Wildlife Research, Alfred-Kowalke-Strasse 17, 10315 Berlin, Germany
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