Compromised Survivorship in Zoo Elephants
Ros Clubb,1
Marcus Rowcliffe,2
Phyllis Lee,3,4
Khyne U. Mar,2,5
Cynthia Moss,4
Georgia J. Mason6*
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.
2 Institute of Zoology, Zoological Society of London, London NW1 4RY, UK.
3 Psychology Department, University of Stirling, Stirling FK9 4LA, UK.
4 Amboseli Trust for Elephants, Post Office Box 15135, Nairobi, Kenya.
5 Department of Animal and Plant Sciences, University of Sheffield, Western Bank, Sheffield S10 2TN, UK.
6 Animal Sciences Department, University of Guelph, Guelph N1G 2M7, Canada.
* To whom correspondence should be addressed. E-mail: gmason{at}uoguelph.ca
