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Cited by 171Wildlife Ecology and ConservationAnimal Behavior and Welfare StudiesMarine animal studies overview

Compromised survivorship in zoo elephants

Open access
Clubb, Ros, Rowcliffe, Marcus, Lee, Phyllis, Mar, Khyne U., Moss, Cynthia, Mason, Georgia J.·2008·Science
DOI 10.1126/science.1164298
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Abstract

We analyzed data from over 4500 elephants to show that animals in European zoos have about half the median life span of conspecifics in protected populations in range countries. This discrepancy is clearest in Asian elephants; unlike African elephants in zoos, this species' infant mortality is very high (for example, twice that seen in Burmese timber camps), and its adult survivorship in zoos has not improved significantly in recent years. One risk factor for Asian zoo elephants is being moved between institutions, with early removal from the mother tending to have additional adverse effects. Another risk factor is being born into a zoo rather than being imported from the wild, with poor adult survivorship in zoo-born Asians apparently being conferred prenatally or in early infancy. We suggest stress and/or obesity as likely causes of zoo elephants' compromised survivorship.

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Crossref · 10.1126/science.1164298

Cites

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  • Asian calves removed from their mothers at a young age tended to have poorer outcomes.

    “Asian calves removed from their mothers at a young age tended to have poorer outcomes”

    From Continuing challenges of elephant captivity: the captive environment, health issues, and welfare implications (2024) · cites this paper as Clubb et al., 2008

    In “Exploring variance in survivorship in zoo populations” (page unavailable), the paper reports that the age at which zoo-born Asian calves were separated from their mothers had no significant effect on survival (p=0.17). It does not report poorer outcomes for calves separated younger; the elevated mortality it finds concerns transfers between zoos, not age at separation. (LLM, conf=0.84)

    Checked by a reasoning model — may be wrong.

    Experimental — accuracy not yet measured

  • Inter-zoo transfers lessened Asian elephant survivorship, an effect that lasted four years post-transfer.

    “inter-zoo transfers lessened Asian elephant survivorship, an effect that lasted four years post-transfer”

    From Continuing challenges of elephant captivity: the captive environment, health issues, and welfare implications (2024) · cites this paper as Clubb et al., 2008

    The paper reports that transfers reduced Asian elephant survivorship, but not that the effect lasted four years. In “Exploring variance in survivorship in zoo populations,” it reports elevated mortality hazard for one year after a first transfer and for up to six years after a second transfer. (LLM, conf=0.91)

    Experimental — accuracy not yet measured

  • Asian and African elephants in zoos have a median lifespan of between 16.9-18.9 years.

    “However, Asian and African elephants in zoos have a median lifespan of between 16.9-18.9years (Clubb et al., 2008), with captive born Asian elephants having higher adult mortality rates than those born in the wild (Clubb et al., 2008”

    From Continuing challenges of elephant captivity: the captive environment, health issues, and welfare implications (2024) · cites this paper as Clubb et al., 2008

    The Results report median lifespans of 16.9 years for zoo-born African elephants and 18.9 years for captive-born Asian elephants. The figures match the claimed range, but the claim omits the birth-origin restriction and presents them as medians for zoo elephants generally. (LLM, conf=0.88)

    Experimental — accuracy not yet measured

  • Survivorship had improved for African elephants in zoos since 1960, but not for Asian elephants.

    “as compared to findings by Clubb et al. (2008) that survivorship had improved for African elephants in zoos since 1960, but not for Asian elephants”

    From Continuing challenges of elephant captivity: the captive environment, health issues, and welfare implications (2024) · cites this paper as Clubb et al., 2008

    The supporting tables report a significant recent improvement in survivorship for adult African zoo elephants, but no significant improvement for adult Asians. The Methods say the zoo data cover animals living in the population from 1960. The claim omits the adult qualifier: the paper did not find an improvement for African infants or juveniles. (LLM, conf=0.88)

    Experimental — accuracy not yet measured

  • Captive African elephants exhibit a mortality rate that is 2.8 times higher than their free-ranging counterparts.

    “Captive African elephants exhibit a mortality rate that is 2.8 times higher than their free-ranging counterparts (Clubb et al., 2008”

    From Continuing challenges of elephant captivity: the captive environment, health issues, and welfare implications (2024) · cites this paper as Clubb et al., 2008

    In “Exploring variance in survivorship in zoo populations” (page not supplied), the paper estimates a mortality risk 2.8 times higher for adult African elephants in zoos in 2005 than for its reference population when human-caused deaths are excluded. The claim omits the adult age group, the year, and the natural-mortality comparator, presenting the estimate as a general mortality rate for captive versus free-ranging African elephants. (LLM, conf=0.91)

    Experimental — accuracy not yet measured

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Cites

Flagged first, then by citations

Research works printed but not linked: 14

  1. [10]10. R. Clubb, G. Mason, A Review of the Welfare of Zoo Elephants in Europe (RSPCA, Horsham, UK, 2002).
  2. [12]12. K. U. Mar, The demography and life history strategy of timber elephants in Myanmar. PhD Thesis (University College London, London, 2007).
  3. [26]26. Obesity -the report of the British Nutrition Foundation Task Force (Blackwell Science, Oxford UK, 1999).
  4. [30]30. Acknowledgments: RC thanks Ruth Ripley for statistical advice; RC and GJM thank the RSPCA for past funding, Amelia Terkel and Ton Dorrestyn for access to studbook data, Miranda Stevenson and Olivia Walter for help with analysis of studbook data; KUM thanks Prospect Burma Foundation, Charles Wallace Burma Trust, Three Oaks Foundation, Whitley-Laing Foundation (Rufford Small Grants), Toyota Foundation, Fantham Memorial Research Scholarship and University College London for funding, and Thoung Nyunt for comments and help in compiling data. GJM thanks NSERC for funding, Anna Kate Shovellor and Brian McBride for advice re. obesity research, and several others for help with in and ex situ costs; PL & CM thank the many donors to AERP who have helped fund the long-term monitoring, and to S. Sayialel, N, Njiraini and K. Sayialel for invaluable contributions to data collection. 4. References : K. Ange et al., in Proceedings of the Nutrition Advisory Group Conference (Lake Buena Vista, Florida) 4, 5-14 (Association of Zoos and Aquariums, Silver Spring MD, 2001) Associated Press, Bongo drums up wildlife support. Rhino News June 11 th 2003.
  5. [31]31. AZA Elephant Manager's Meeting, Orlando, Florida, 10-21 January 2005 (Association of Zoos and Aquariums, Silver Spring MD, 2005) AZA (Association of Zoos and Aquariums) Zoo elephants thriving. Press release Dec. 12 2006. http://www.aza.org/Newsroom/ZooElephantsThriving/
  6. [38]38. G. Caughley, Analysis of Vertebrate Populations. (Wiley, New York, 1977).
  7. [44]44. V. Hayssen, A. van Tienhoven, A. van Tienhoven, Asdell's Patterns of Mammalian Reproduction (Cornell University Press, Ithaca, NY, 1993).
  8. [53]53. T. Maliti, "Huge problems hamper Kenya's national parks". Mail & Guardian 12 Sept. 2005; http:www.mg.co.za K. U. Mar, The Tiger Paper 23(4), 6-13 (1996).
  9. [55]55. K. U. Mar, The demography and life history strategy of timber elephants in Myanmar. PhD Thesis (University College London, London, 2007).
  10. [58]58. C. J. Moss, J. H. Poole in Primate Social Relationships: an Integrated Approach, R. A. Hinde, Ed. (Blackwell, Oxford, 1983) pp. 315-325.
  11. [59]59. A. Nelson, P. Bidwell, P., C. Sillero-Zubiri, "A review of human-elephant conflict management strategies", www.peopleandwildlife.org.uk/crmanuals/HumanElephantConflictP&WManual (2003).
  12. [64]64. W. Siler, Ecology 60, 750 (1979).
  13. [66]66. R. Sukumar, The Asian Elephant: Ecology and Management (CUP, Cambridge, 1989).
  14. [67]67. R. Sukumar, The Living Elephants: Evolutionary Ecology, Behaviour and Conservation (OUP, Oxford, 2003).

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Authors
Clubb, R., Rowcliffe, M., Lee, P., Mar, K. U., Moss, C., & Mason, G. J.
Affiliations
  • University of Stirling (GB)
  • Royal Society for the Prevention of Cruelty to Animals (RSPCA), Wilberforce Way, Southwater, West Sussex, RH13 9RS, UK.
Corresponding author
Mason, Georgia J.
ORCID
Venue
Science
Publisher
American Association for the Advancement of Science (AAAS)
Published
2008-12-12
Volume
322
Issue
5908
Pages
1649-1649
ISSN
  • 0036-8075 (ISSN-L)
  • 1095-9203
DOI
10.1126/science.1164298
OpenAlex
W2118479050
Semantic Scholar
771c16cdac0a59d1387393933674e982868d712d
Cited by
171
References
2
Citations by year
2026: 6 · 2025: 4 · 2024: 9 · 2023: 12 · 2022: 10 · 2021: 17 · 2020: 11 · 2019: 16 · 2018: 11 · 2017: 6 · 2016: 15 · 2015: 7 · 2014: 8 · 2013: 10 · 2012: 7
FWCI
6.03
Type
journal article
Language
en
Open access
Licence
public-domain
Locations
  • Science (publishedVersion)
  • PubMed (publishedVersion)
  • Stirling Online Research Repository (University of Stirling) (submittedVersion, public-domain)
  • The Atrium (University of Guelph) (submittedVersion)
  • UCL Discovery (University College London) (submittedVersion)
Topics
  • Physical Sciences › Environmental Science › Ecology › Wildlife Ecology and Conservation
  • Health Sciences › Veterinary › Small Animals › Animal Behavior and Welfare Studies
  • Physical Sciences › Environmental Science › Ecology › Marine animal studies overview
Keywords
zoo elephants, Asian elephant, Loxodonta africana, captive animal welfare, adult survivorship, lifespan, infant mortality, stress, obesity, wildlife conservation
MeSH terms
Africa, Animals, Animal Welfare, Animals, Wild, Animals, Zoo, Asia, Myanmar, Elephants, Female, Kenya, Longevity, Mortality, Kaplan-Meier Estimate

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