December 12, 2008
Elephants Live Longer In The Wild
Elephants living in zoos have shorter lives than their wild counterparts, according to a new study that will most certainly stir debate about their captive situations.
Researchers compared the life spans of elephants in European zoos with those living in Amboseli National Park in Kenya and others working on a timber enterprise in Myanmar.
Animals in the wild or in natural working conditions had life spans twice that or more of their relatives in zoos.
The new findings were published in the journal Science where researchers wrote obesity is a leading cause of death in adult zoo elephants, and stress is a killer of young animals moved between zoos.
In recent years, animal care activists have campaigned to discourage keeping elephants in zoos due to the lack of space and small numbers of animals that can be kept in a group.
The median life span for African elephants in European zoos was 16.9 years, compared with 56 years for elephants who died of natural causes in Kenya's Amboseli Park.
For the more endangered Asian elephants, the median life span in European zoos was 18.9 years, compared with 41.7 years for those working in the Myanmar Timber Enterprise. Myanmar is the country formerly known as Burma.
Ros Clubb from Britain's Royal Society for the Prevention of Cruelty to Animals (RSPCA) says diet and lifestyle are the key factors influencing elephant lifespan in zoos.
"The vast majority are overweight in zoos, this could explain the high still-birth rates and why they're dying early. Bigger mothers have bigger calves and more of these are still-born," she said.
Early death was also more likely to occur in captive animals born in the wild or transferred between zoos.
"In the wild they live in large stable groups, separation does cause stress; we know this from studies of other species," she said.
The study did bring some good news. Life spans of zoo elephants have improved in recent years, suggesting an improvement in their care, said author Georgia J. Mason of the animal sciences department at the University of Guelph, Canada.
But, she added, "protecting elephants in Africa and Asia is far more successful than protecting them in Western zoos."
There are about 1,200 elephants in zoos, half in Europe, Mason said.
"One of our more amazing results" was that Asian elephants born in zoos have shorter life spans than do Asian elephants brought to the zoos from the wild, she said.
She noted zoos typically lack large grazing areas that elephants are used to in the wild.
Experts say zoo animals often are alone or with one or two other unrelated animals, while in the wild they tend to live in related groups of eight to 12 animals.
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