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Fecundity and population viability in female zoo elephants: problems and possible solutions

Published online by Cambridge University Press:  01 January 2023

R Clubb ,
M Rowcliffe ,
P Lee ,
KU Mar ,
C Moss  and
GJ Mason
R Clubb
Affiliation:
Wildlife Department, RSPCA, Wilberforce Way, Southwater, West Sussex RH13 9RS, UK
M Rowcliffe
Affiliation:
Institute of Zoology, Zoological Society of London, London NW1 4RY, UK
P Lee
Affiliation:
Department of Psychology, University of Stirling, Stirling FK9 4LA, UK Amboseli Trust for Elephants, PO Box 15135, 00509 Langata, Nairobi, Kenya
KU Mar
Affiliation:
Department of Animal and Plant Sciences, University of Sheffield, Sheffield S10 2TN, UK
C Moss
Affiliation:
Amboseli Trust for Elephants, PO Box 15135, 00509 Langata, Nairobi, Kenya
GJ Mason*
Affiliation:
Animal Sciences Dept, University of Guelph, Guelph N1G 2M7, Canada
*
* Contact for correspondence and requests for reprints: gmason@uoguelph.ca
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Abstract

We previously reported that African (Loxodonta africana) and Asian (Elephas maximus) female elephants in European zoos have shorter adult lifespans than protected conspecifics in range countries. This effect was the cause of greatest concern in Asian elephants, and risk factors within this species included being zoo-born, transferred between zoos, and possibly removed early from the mother. Here, we investigate these risk factors further; assess fecundity and sustainability in European zoos; and propose testable hypotheses as to the causes of these animals’ problems. Although imported wild-born Asian elephants live longer than zoo-born conspecifics, being imported when juvenile or adult appears no more protective than being imported in infancy, suggesting that the benefits of being wild- rather than zoo-born are conferred early in life. Zoo-born Asian neonates are significantly heavier than those born to working animals in range countries, with a possible tendency to be fatter. In zoos, African elephants have tended to be removed from their mothers at older ages than young Asians, and were also transferred between zoos significantly less often: factors that could possibly underlie this species’ lower calf losses and improving adult survivorship in Europe. Both species have low fecundity in European zoos compared to in situ populations, and are not self-sustaining, declining at approximately 10% per annum if reliant on captive-bred females under historically prevailing conditions. Data from other species suggest that stress and/or obesity are parsimonious explanations for the suite of problems seen. We recommend specific screens for testing these hypotheses, and for potentially identifying vulnerable individuals within the extant zoo populations.

Keywords

African elephantanimal welfareAsian elephantfecunditypopulation viabilitysurvivorship
Type
Research Article
Information
Animal Welfare , Volume 18 , Issue 3 , August 2009 , pp. 237 - 247
Copyright
© 2009 Universities Federation for Animal Welfare

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