ROBERT SIEGEL, host:
There is new fodder in the debate over the welfare of elephants. A study released today suggests elephants in zoos may not live as long as those in the wild. NPR's Joe Palca has our story.
JOE PALCA: Elephants were not the first animal Georgia Mason focused on. While at the University of Oxford, she studied minks and foxes on fur farms. Now, she's a professor at the University of Guelph in Canada, where she's turned her attention to elephant welfare.
Dr. GEORGIA MASON (Animal Science Department, University of Guelph in Canada): There had been suggestions that animals live a short time compared with animals in the wild. And so we just decided to investigate this objectively.
PALCA: So Mason and her colleagues looked at birth and death records from European zoos and compared them with similar records from elephants living in Myanmar for Asian elephants and the Amboseli National Park in Kenya in the case of African elephants.
Dr. MASON: In the African elephants, we found that infant mortality is just fine in European zoos, so that's good news. Juvenile survivorship is fine. But in adulthood, animals in zoos are dying earlier, so they're less likely to make it into old age.
PALCA: The news for Asian elephants in zoos is also grim. In the Myanmar elephants she studied, half the animals in the reserve lived longer than 41 years.
Dr. MASON: Whereas in European zoos, half of all animals are dead by the age of 19, which is quite a dramatic difference.
PALCA: Mason's research appears in the journal Science. But Robert Wiese says you need to give these numbers a little context. Wiese is an elephant expert at the San Diego Zoo. He says elephant populations are declining around the world, and the elephants in Myanmar and the Amboseli Park have received special protections. When you make comparisons about life expectancy, Wiese says you have to decide whether you consider all the threats an elephant faces.
Mr. ROBERT WIESE (Elephant Expert, San Diego Zoo): Do you include poaching? Do you not include poaching? You know, is that a part of the modern natural situation or not?
PALCA: Another objection to Mason's work is that it relies on zoo data that in some cases is nearly a half century old. Paul Boyle is senior vice president for conservation and education at the Association of Zoos and Aquariums.
Dr. PAUL BOYLE (Senior Vice President for Conservation, Association of Zoos and Aquariums): When you reach back 48 years, my comment would be, you know, just like hospitals and surgeons that we experience today - they have much greater success today than they did 20 years ago, never mind, 48 years ago. So, there's a significant bias in this paper to include data back at a time when nobody was as good at keeping animals healthy and alive as our institutions are today.
PALCA: Boyle says Mason and her colleagues have an agenda.
Dr. BOYLE: If you scratch away at the references and the groups that were involved in this, there's a very close connection to sort of anti-zoo groups.
PALCA: But study author Georgia Mason insists she's just trying to take the debate over elephants and zoos out of the realm of anecdote and opinion and put it in the realm of science.
Dr. MASON: My agenda is to get decisions informed by data rather than passion. And my suspicion is on both sides, both the zoo industry and the anti-zoo crowd, both tend to kind of yell, you know, this enclosure is fine. Oh no, it isn't. I think it's time these things are just tackled with data. They are empirical questions.
PALCA: In fact, her data do show that some of the changes zoos have made in recent years are helping animals live longer. By collecting more data on zoo populations, she says it may be possible to tease out what measures really help elephants live long and healthy lives in captivity. Joe Palca, NPR News, Washington.
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