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Abstract
AbstractAll mammals experience different life stages as they develop, each of which is characterised by particular physical and behavioural changes. Despite the emergence of sophisticated behaviour analysis techniques, the ways in which social behaviour varies by life stage, and how this is influenced by an individual’s sex, is relatively understudied in most social mammals other than primates and elephants. Understanding the social requirements of mammals should be a central and critical component to their conservation, captive management and welfare. Here, we apply social network analysis techniques to understand how social behaviour differs with life stage in the giraffe, a gregarious fission–fusion mammal. We studied two wild populations of giraffes in Kenya and found that adolescents have significantly stronger associations with adolescents of their own sex first and foremost, then adults of their own sex. Other associations were significantly lower than would be expected, or non-significant. Our results suggest that adolescence in both male and female giraffes shares similar features to adolescence in other social mammal species. We discuss how the application of such knowledge might improve the management and welfare of captive giraffes.
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The utilisation of woody species by male and female elephants in the Serengeti National Park, a nutrient-rich savanna. EUR J WILDLIFE RES 2021. [DOI: 10.1007/s10344-021-01523-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Burger AL, Hartig J, Dierkes PW. Biological and environmental factors as sources of variation in nocturnal behavior of giraffe. Zoo Biol 2021; 40:171-181. [PMID: 33666286 DOI: 10.1002/zoo.21596] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2021] [Accepted: 02/09/2021] [Indexed: 01/01/2023]
Abstract
Upon a drastic decline of the giraffe population in the wild, conservation efforts and therefore the role of zoos have become more important than ever. With their unique opportunities, zoos provide excellent conditions to study animal behavior, expanding the knowledge about the giraffe's behavior repertoire and their ability to adapt. This study therefore examined the nocturnal behavior of 63 giraffe living in 13 different EAZA zoos across Germany and the Netherlands. Giraffe were observed and videos recorded via infrared sensitive cameras during the winter seasons 2015-2018. The observation period spanned nightly from 17:00 to 7:00. Thus, 198 nights, with a total of 2772 h were recorded and analyzed. Linear mixed models were then used to assess potential biological and environmental factors influencing behavior during the dark phase. Results show that individual variables such as age, subspecies and motherhood determined nocturnal activity and sleep behavior most. Among the variables studied, husbandry conditions and environmental factors complying with EAZA standards had no influence on the giraffe's nocturnal behavior. By combining nocturnal activity analyses and an assessment of potential influencing factors, our findings present a holistic approach to a better understanding of captive giraffe behavior and allow for management implications.
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Affiliation(s)
- Anna Lena Burger
- Bioscience Education and Zoo Biology, Goethe University Frankfurt, Frankfurt am Main, Germany
| | - Johannes Hartig
- Department of Educational Quality and Evaluation, DIPF, Leibniz Institute for Research and Information in Education, Frankfurt am Main, Germany
| | - Paul W Dierkes
- Bioscience Education and Zoo Biology, Goethe University Frankfurt, Frankfurt am Main, Germany
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Bond ML, Lee DE, Farine DR, Ozgul A, König B. Sociability increases survival of adult female giraffes. Proc Biol Sci 2021; 288:20202770. [PMID: 33563118 DOI: 10.1098/rspb.2020.2770] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Studies increasingly show that social connectedness plays a key role in determining survival, in addition to natural and anthropogenic environmental factors. Few studies, however, integrated social, non-social and demographic data to elucidate what components of an animal's socio-ecological environment are most important to their survival. Female giraffes (Giraffa camelopardalis) form structured societies with highly dynamic group membership but stable long-term associations. We examined the relative contributions of sociability (relationship strength, gregariousness and betweenness), together with those of the natural (food sources and vegetation types) and anthropogenic environment (distance from human settlements), to adult female giraffe survival. We tested predictions about the influence of sociability and natural and human factors at two social levels: the individual and the social community. Survival was primarily driven by individual- rather than community-level social factors. Gregariousness (the number of other females each individual was observed with on average) was most important in explaining variation in female adult survival, more than other social traits and any natural or anthropogenic environmental factors. For adult female giraffes, grouping with more other females, even as group membership frequently changes, is correlated with better survival, and this sociability appears to be more important than several attributes of their non-social environment.
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Affiliation(s)
- M L Bond
- Department of Evolutionary Biology and Environmental Studies, University of Zurich, Zurich, Switzerland.,Wild Nature Institute, Concord, NH, USA
| | - D E Lee
- Wild Nature Institute, Concord, NH, USA.,Department of Biology, Pennsylvania State University, University Park, PA, USA
| | - D R Farine
- Department of Evolutionary Biology and Environmental Studies, University of Zurich, Zurich, Switzerland.,Department of Collective Behavior, Max Planck Institute of Animal Behavior, Konstanz, Germany.,Center for the Advanced Study of Collective Behaviour, University of Konstanz, Konstanz, Germany
| | - A Ozgul
- Department of Evolutionary Biology and Environmental Studies, University of Zurich, Zurich, Switzerland
| | - B König
- Department of Evolutionary Biology and Environmental Studies, University of Zurich, Zurich, Switzerland
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Burger AL, Fennessy J, Fennessy S, Dierkes PW. Nightly selection of resting sites and group behavior reveal antipredator strategies in giraffe. Ecol Evol 2020; 10:2917-2927. [PMID: 32211165 PMCID: PMC7083675 DOI: 10.1002/ece3.6106] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2019] [Revised: 01/21/2020] [Accepted: 01/27/2020] [Indexed: 12/28/2022] Open
Abstract
This study presents the first findings on nocturnal behavior patterns of wild Angolan giraffe. We characterized their nocturnal behavior and analyzed the influence of ecological factors such as group size, season, and habitat use. Giraffe were observed using night vision systems and thermal imaging cameras on Okapuka Ranch, Namibia. A total of 77 giraffe were observed during 24 nights over two distinct periods-July-August 2016 (dry season) and February-March 2017 (wet season). Photoperiod had a marked influence on their activity and moving behavior. At dusk, giraffe reduced the time spent moving and increasingly lay down and slept at the onset of darkness. Body postures that likely correspond to rapid eye movement (REM) sleep posture (RSP) were observed 15.8 ± 18.3 min after giraffe sat down. Season had a significant effect with longer RSP phases during the dry season (dry: 155.2 ± 191.1 s, n = 79; wet: 85.8 ± 94.9 s, n = 73). Further analyses of the influence of social behavior patterns did not show an effect of group size on RSP lengths. When a group of giraffe spent time at a specific resting site, several individuals were alert (vigilant) while other group members sat down or took up RSP. Simultaneous RSP events within a group were rarely observed. Resting sites were characterized by single trees or sparse bushes on open areas allowing for good visibility in a relatively sheltered location.
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Affiliation(s)
- Anna Lena Burger
- Bioscience Education and Zoo BiologyGoethe University FrankfurtFrankfurt am MainGermany
| | - Julian Fennessy
- Giraffe Conservation FoundationWindhoekNamibia
- School of Biological, Earth and Environmental SciencesUniversity of New South WalesSydneyNSWAustralia
| | | | - Paul W. Dierkes
- Bioscience Education and Zoo BiologyGoethe University FrankfurtFrankfurt am MainGermany
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Charry B, Marcoux M, Cardille JA, Giroux‐Bougard X, Humphries MM. Hierarchical Classification of Narwhal Subpopulations Using Social Distance. J Wildl Manage 2020. [DOI: 10.1002/jwmg.21799] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Bertrand Charry
- Natural Resource Sciences, Macdonald CampusMcGill University 21 111 Lakeshore Drive Ste‐Anne‐de‐Bellevue QC H9X 3V9 Canada
| | - Marianne Marcoux
- Fisheries & Oceans CanadaArctic Aquatic Research Division 501 University Crescent Winnipeg MB R3T 2N6 Canada
| | - Jeffrey A. Cardille
- Natural Resource Sciences, Macdonald CampusMcGill University 21 111 Lakeshore Drive Ste‐Anne‐de‐Bellevue QC H9X 3V9 Canada
| | - Xavier Giroux‐Bougard
- Natural Resource Sciences, Macdonald CampusMcGill University 21 111 Lakeshore Drive Ste‐Anne‐de‐Bellevue QC H9X 3V9 Canada
| | - Murray M. Humphries
- Natural Resource Sciences, Macdonald CampusMcGill University 21 111 Lakeshore Drive Ste‐Anne‐de‐Bellevue QC H9X 3V9 Canada
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Fission-fusion dynamics of a megaherbivore are driven by ecological, anthropogenic, temporal, and social factors. Oecologia 2019; 191:335-347. [PMID: 31451928 DOI: 10.1007/s00442-019-04485-y] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2018] [Accepted: 08/08/2019] [Indexed: 10/26/2022]
Abstract
Fission-fusion dynamics hypothetically enable animals to exploit dispersed and ephemeral food resources while minimizing predation risk. Disentangling factors affecting group size and composition of fission-fusion species facilitates their management and conservation. We used a 6-year data set of 2888 group formations of Masai giraffes in Tanzania to investigate determinants of social group size and structure. We tested whether ecological (lion density, vegetation structure, and prevalence of primary forage plants), anthropogenic (proximity to human settlements), temporal (rainy or dry season), and social (local giraffe density, adult sex ratio, and proportion of calves) factors explained variation in group size and sex- and age-class composition. Food availability rather than predation risk mediated grouping dynamics of adult giraffes, while predation risk was the most important factor influencing congregations with calves. Smallest group sizes occurred during the food-limiting dry season. Where predation risk was greatest, groups with calves were in bushlands more than in open grasslands, but the groups were smaller in size, suggesting mothers adopted a strategy of hiding calves rather than a predator-detection-and-dilution strategy. Groups with calves also were farther from towns but closer to traditional human compounds (bomas). This may be due to lower predator densities, and thus reduced calf predation risk, near bomas but higher human disturbance near towns. Sex- and age-based differences in habitat use reflected nursing mothers' need for high-quality forage while also protecting their young from predation. Our results have implications for conservation and management of giraffes and other large-bodied, herd-forming ungulates in heterogeneous environments subject to anthropogenic threats.
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Lewton J, Rose PE. Evaluating the social structure of captive Rothschild’s giraffes (Giraffa camelopardalis rothschildi): Relevance to animal management and animal welfare. J APPL ANIM WELF SCI 2019; 23:178-192. [DOI: 10.1080/10888705.2019.1573682] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Affiliation(s)
- Jack Lewton
- School of Science and the Environment, Faculty of Science & Engineering, John Dalton Building, Manchester Metropolitan University, Manchester, UK
| | - Paul E. Rose
- Centre for Research in Animal Behaviour, College of Life & Environmental Sciences, Washington Singer Labs, University of Exeter, Exeter, UK
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Mramba RP, Andreassen HP, Mlingi V, Skarpe C. Activity patterns of African elephants in nutrient-rich and nutrient-poor savannas. Mamm Biol 2019. [DOI: 10.1016/j.mambio.2018.12.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Bercovitch FB, Berry PSM. Social and demographic influences on the feeding ecology of giraffe in the Luangwa Valley, Zambia: 1973-2014. Afr J Ecol 2017. [DOI: 10.1111/aje.12443] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Fred B. Bercovitch
- Primate Research Institute & Wildlife Research Center; Kyoto University; Inuyama Aichi Japan
- Department of Animal, Wildlife and Grassland Sciences; University of the Free State; Bloemfontein South Africa
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