No Ark: Zoos Shirk Conservation Mission, Critics Charge
Who wants to see a little brown deer?
Maybe no one. Or that’s what worries some conservationists.
The Calamian deer, a short-legged, barrel-chested creature about the size of a Greyhound, is gravely endangered in its Philippine island home, and now, the zoo population that was supposed to save the species for some future return to the wild is near collapse. All because, conservationists fear, no one much wants to see a little brown deer.
The animal is just one of many endangered species that captive breeding might help, several conservation experts say. But studies show zoos devote most of their space to animals under far less threat. The result is a chasm between the public perception that zoos should serve as an ark for endangered species — and reality. Although the Association of Zoos and Aquariums (AZA), a membership and accrediting organization for 240 mostly North American zoos, argues that zoos engage in a wide variety of complex conservation efforts, critics maintain that too often, the facilities are driven by a need to appeal to an admission-paying public and can be reluctant to take on the challenging care many endangered species require.
"We’ve got to go back and rethink what we’re doing, and it needs to start at a national level," says Jeff Holland, curator of mammals for the Los Angeles Zoo and Botanical Gardens. "Are zoos conservation organizations, here to conserve species that are going extinct? Or are we here to entertain and educate people, and managing endangered species — that’s somebody else’s job?"
Few Endangered Animals in Captivity
Zoos seem to be answering Holland’s question with their collections.
- A study published online in December in the journal PLoS One showed that only 18 percent of land animals in zoo collections are threatened or endangered. Of the nearly 4,000 species held in captivity, only 691 are threatened or endangered.
- Individual zoos often hold too few representatives of a species to engage in a breeding program, a report this year in World Association of Zoos and Aquariums News revealed. Some 880 species are represented by only a single animal in zoos worldwide, while just 10 species account for 53 percent of all animals kept in zoos around the globe.
- The same report showed that endangered tigers and somewhat less threatened lions are kept by more zoos than any other mammals, but domestic livestock, especially goats and sheep, are the next best represented species.
- Threatened bird species are particularly underrepresented in zoos. About 8 percent of birds in zoos are threatened or endangered, the PLoS study showed.
- Reptiles are best represented, with 40 percent of the total zoo populations composed of threatened or endangered species.
- About 27 percent of zoo mammal species are endangered, and 25 percent of amphibian species in zoo collections are endangered.
The data on endangered species in zoos are so grim, Dalia A. Conde, a conservation biologist at the University of Southern Denmark, and her PLoS One paper co-authors concluded, that there is little sign that zoos consider conservation status at all in maintaining their collections. Of the 59 taxonomic orders represented in zoos, only two had a higher proportion of threatened species "than would be expected if species were selected at random," the study says. An order is a classification made up of similar types of animals; primates, carnivores, whales and insect-eaters each are a taxonomic order.
Paul J. Boyle, senior vice president for conservation and education for the AZA, says his organization knows there’s a problem and is educating its members to improve the conservation picture. "We’re not unaware of the things Dalia [Conde] is finding out. She put a finer edge on the statistics," he says. But transformation will take time. "You can’t change these exhibits overnight," Boyle says. Nonetheless, the AZA has been ramping up its conservation emphasis; last summer its board produced a statement that said its member institutions "need to be substantially involved in conservation."
Efforts in the Field
The news is not all bad when talking about zoos and conservation. While the representation of endangered species in zoos is low, the facilities are often more active in habitat preservation and restoration than ever before. The World Association of Zoos and Aquariums (WAZA), for instance, is the third-largest contributor to habitat conservation behind only the World Wildlife Fund and the Nature Conservancy, contributing $350 million annually. The AZA recently tallied the field conservation activities of its member zoos at $160 million per year, Boyle says. But Jens-Ove Heckel, DVM, director of Zoo Landau in der Pfalz, Germany, says while such efforts are impressive and imperative, they’re not enough. "That’s very important if you want to save species. But many of these species we are dealing with will only survive — for at least a certain time — in zoos," Heckel told Vetstreet.
"Zoos are putting more money for conservation out in the field, which is great," Holland of the Los Angeles Zoo agrees. "That’s one of the things we need to do, and we do that pretty darn well. But part of conservation is managing animals in captivity and coordinating that between several zoos," he says. According to Holland, zoos have done that very thing successfully for some species, including a red-brown African forest antelope known as the bongo; the Arabian oryx, a white antelope with long, straight horns; the black-footed ferret; the California condor; and a small monkey called the golden lion tamarin.
A Battle for Exhibit Space
But many more species go begging. It’s a problem that could send the endangered Calamian deer into extinction in captivity just as it winks out in the wild. In a recent WAZA article by Holland; Heckel; Roland Wirth, founder of the Zoological Society for the Conservation of Species and Populations (ZGAP); and Douglas Richardson, animal collection manager for Highland Wildlife Park in Scotland, the authors said the space that rare deer need is taken up by collections of local, abundant deer. The authors report that globally, zoos devote 75 exhibit spaces to abundant species such as white-tailed deer, mule deer and elk, but they keep only 20 spaces for six species of deer listed as vulnerable or endangered by the International Union for Conservation of Nature. IUCN tracks the conservation status of species all over the world in its Red List of Threatened Species.
This is where the pudgy Calamian deer foundered. When conservationists realized the Calamian deer was about to go extinct in the Philippines in 1995, the San Diego Zoo created a successful captive breeding program, and San Diego’s little herd grew well over the next several years. But as it grew, Holland says, no other zoos came forward to take in members of the growing herd of plain-Jane deer. With nowhere to put excess animals, San Diego was forced to halt breeding, which proved near disastrous. Interrupting breeding in many species leads to infertility. When keepers tried to return some females to breeding after a hiatus, the animals could no longer produce offspring.
And then it got worse. A lethal wasting disease struck the shrinking population. Veterinarians still don’t know what causes the disease, although Holland says it is not related to the chronic wasting disease found in some wild elk and deer populations in the United States.
By 2008, the Calamian population seemed sure to vanish. That’s when the LA Zoo and the Phoenix Zoo stepped in to help. "We came in at the last minute," Holland says. "I wish we had done it earlier, but we didn’t act until they were barely hanging on." Now the total captive population is down to 10 individuals, about half of them of breeding age. Although it’s possible to restart a population with such a small number of founders, the loss of genetic diversity leaves the species at high risk of genetic defect from inbreeding.
The Disney Effect
The little deer is among several species in such straits. An endangered animal known as a Visayan warty pig can’t find zoos willing to take it in. Instead, common warthogs, benefiting from the publicity they received in the animated Disney film The Lion King, take up available exhibit space. Disney depictions of meerkats boosted their popularity, too. "Everybody needed meerkats; everybody needed warthogs," Holland says. "Those popular films do drive exhibits. Madagascar, the one with the lemurs, was another classic example of how zoos are influenced by entertainment." Madagascar made endangered ring-tailed lemurs so popular, they’re now over-represented in zoos compared to more endangered animals in the lemur family. While more than 3,200 of the charming animals are recorded in a worldwide database of zoo populations, there are far fewer numbers of several lemurs facing even greater risk of extinction — animals the IUCN considers "critically endangered." In some cases, there are fewer than two dozen individuals spread across six different zoos.
But popularity isn’t the sole driver of collection decisions. American zoos began shedding endangered macaque monkeys from collections several years ago in favor of less threatened animals. At fault are elevated rates of herpes B virus in the monkeys, Heckel of Zoo Landau says. But the veterinarian, who specializes in zoonoses — diseases that are transmittable between animals and man — says there is no reason to abandon the animals. In fact, zoos have ample experience dealing with zoonotic diseases, such as hepatitis B, elevated levels of which have been seen in chimpanzees, orangutans and gibbons. "Yes, you should be careful if you deal with either blood or feces of a primate. If you are not 100 percent certain of its health status, you shouldn’t have your breakfast close to an enclosure — that’s just common sense," Heckel says. "Caution is good, but panicking is not."
For People or for Animals
Another factor in zoo collection decisions is tension between creating a wonderful visitor experience and acting for the good of the species, critics say. Perhaps few animals have been hurt more by that conflict than endangered birds, says Wirth, founder of the Zoological Society for the Conservation of Species and Populations, a Germany-based group involved in rescue efforts for several endangered species. It turns out the magical walk-through bird displays, where a dozen species or more flit over visitors’ heads, often stress birds in ways that prevent breeding, Wirth says.
"If you select birds carefully, they may stay alive and lead a normal-length life in these enclosures, but it is almost impossible to make them reproduce in sufficient numbers," Wirth says. Few birds in the wild would choose to live permanently with so little privacy and so many other species, he says. They may congregate at a bird feeder temporarily, but when they nest and breed, they’re on their own. The mix of birds in an open exhibit could turn one species’ chicks into another species’ lunch. Or the dietary requirements of one bird species might lead to undernourishment in another. Finding zoos to host endangered birds, as a result, is a challenge.
"We don’t find space. Most zoos give in to the public presumption [of what birds like] rather than explaining what they need," he says.
At the heart of the problem, commenters suggest, is the shrinking influence of biologists in zoo management.
"We’re becoming more business- and entertainment-oriented," Holland says. "It starts from the top down. As you get less and less directors who are animal-based, what I see happening is a new generation comes in and they’re not as exposed to the conservation message."
Boyle says the AZA also focuses on that issue. "More and more directors don’t come from the animal field,” he says. “We spend a good bit of time working with directors about the need for threatened and endangered species in our collection, that these species are an opportunity for us to be leaders in protecting species that have no place to go."
Without change, the current picture of threatened and endangered species in zoo collections could leave some asking what zoos are really for if their priority isn’t saving animals. "We should really be a lifeboat for as many species as we can," Heckel says. "We as mankind are doing a bad job taking care of what has been given to us. We have an obligation."