Only the survival rates of females were analyzed because of their importance to future populations. For African elephants , the median life span is 17 years for zoo-born females, compared to 56 years in the Amboseli National Park population. For Asian elephants , the results are "much more worrying because they are the rarer of the two species," Mason said. Zoo females only live 19 years—about half the life span of the Myanma timber elephants, which, on average, survive until What's more, the team discovered that Asian elephants bred and born in captivity died earlier than those imported into zoos from the wild.
Mason doesn't know why captive-bred elephants are dying sooner than their wild-caught counterparts. But if healthy adults are not able to live long enough reproduce, then the captive populations in Europe won't be self-sustaining—a problem that American zoos already face. To keep zoo elephants alive longer, the authors recommend routine screening for obesity something that's done in U. Checking this biological marker, which shows that the body's immune system is battling sickness, would allow zoo officials to intervene before the animal is seriously ill, Mason said.
He said making a comparison between the lifespan of captive and wild elephants may seem deceptively simple. In Wiese co-authored a paper in the journal Zoo Biology showing the opposite of Mason's findings: that zoo elephants live as long as those in the wild.
He said that within the last decade accredited facilities have made huge improvements in the care of captive elephants by providing better nutrition to combat obesity, as well as environmental enrichment activities that reduce stress. All rights reserved. Wild and Long-Lived Mason and colleagues looked at data from more than 4, wild and captive African and Asian elephants. We are the longest-lived land mammal, although there are a number of marine species that outlive us — bowhead whales can live for years.
Home Animal Facts Mammals Which mammal lives the longest? A happy hedgehog in Scotland. If there is not a lot of room for them to roam in their enclosures, they often become depressed. Elephants are used to living in wide-open spaces, but many zoos cannot provide that type of enclosure, so the elephant has to live in a small area and is not very happy because of it. Elephants are not built for standing in one place for a long period of time, they are built for wandering and walking nearly constantly.
But at a zoo, they often end up standing in one place for a long time out of boredom or lack of stimulation. Elephants are social creatures and often live in herds with other elephants, although Asian elephants typically live in herds of elephants, and male elephants tend to live like a bachelor; alone.
Zoos often cannot accommodate more than one or two elephants at a time, so many elephants are lonely. This can lead to depression, which can shorten their lifespan.
Many elephants develop diseases while in captivity such as herpes and tuberculosis, which are detrimental to their health and severely shortens their life expectancy.
Zoos and conservation programs are doing everything they can to give elephants a long and happy life, but they are complex and difficult creatures to care for. Have a fact or detail to share? I love to cover food, animals, and destinations around the world. I also blog about photography at ClickLikeThis. What Do Elephants Eat? Despite the findings, zoo scientists deny their elephants fare poorly.
Wiese says that the study, at best, is a reflection of the way zoos once were run and does not take into account animal-friendly changes that have been made, such as leaving offspring with their mothers longer periods of time. It's going to be a long period before we can tell how we're doing today. He says seven of the zoo's eight adult African elephants were imported from the Mkhaya Game Reserve and Hlane Royal National Park in Swaziland in , where burgeoning elephant populations were set to be culled.
They are all about 17 years old today. An additional African female elephant, Tembo, who previously appeared in the TV series Born Free , has been at the zoo for 20 years and is now probably 36 years old, according to a zoo spokesperson.
Wiese argues that zoos are important to provide visitors who may not otherwise have the opportunity to see wild animals up close and personal. By doing so, he contends, they make a personal connection with, say, elephants, encouraging them to donate time and money to conservation projects in their home countries designed to protect them. And life in the wild is not particularly idyllic compared with captivity: Of 1, elephants in the Amboseli sample, were killed by ritual spearing, gunshot wounds, or other mishaps.
Besides, Wiese notes, survivorship is not the only gauge of an animal's quality of life, a point even Mason concedes.
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