The Issues



Abnormal behaviour and early deaths in zoos

"[I am] too far removed from the animals; they're the last thing I worry about with all the other problems."--former director of the Atlanta Zoo

 The term "zoochosis" refers to a range of psychological problems, known as stereotypies, which are brought on by the stresses of captivity and the animals' inability to express their natural behaviours. They are a series of repeated movements which serve no purpose, and include excessive and obsessive grooming, chewing, licking, and self-mutilation, as well as rocking, swaying, pacing in regimented circles, head-tossing and neck-stretching, and air-biting.  Many of these same stereotypies can be seen in human beings suffering from mental illness. Giraffes and camels continuously lick the bars and walls of their enclosures.  Bears and elephants pace endlessly and sway to and fro.  Big cats chew their legs and tails to the point of mutilation.  Some animals, like parrots and primates, will tear out their own fur or feathers, grooming themselves even after their skin is bald and bleeding.  Gorillas and chimpanzees rock back and forth, hitting their heads against the walls of their cages, repeatedly vomiting and then eating their own vomit, as well as playing with and eating their own excrement.  These behaviours are not seen in wild animals.

Tiger pacing in zoo.

A wild tiger's home range is between seven and forty square miles, depending on sex and prey availability. In zoos, they pace back and forth endlessly. (Photo: Jo-Anne McArthur, We Animals)

An Oxford University study carried out over four decades and involving the analysis of 1,200 journal articles published worldwide found that wide-ranging carnivores like polar bears, cheetahs, lions, and tigers are so negatively affected by captivity that zoos should stop keeping them altogether or at least fundamentally change the conditions under which they are kept.1  The study also noted, however, that changing the design and size of enclosures and altering feeding schedules did nothing to improve the welfare of the animals and that the problems associated with captivity--specifically, endless pacing and high infant mortality--did not improve.2

Polar bears, for example, have a home range of about 31,000 square miles.  Their enclosures in zoos are about one-millionth of that size.  As a result, polar bears in zoos spend about 25 percent of their day pacing or swimming in circles.3 In the wild, polar bears live an average of 15 to 18 years; in captivity, 75% die before their 15th birthday.4

The Oxford University study also found that about 40 percent of captive elephants display stereotypies, swaying, circling, bobbing their heads or biting at the bars of their cages.  In fact, it is becoming more widely known that elephants tend to do very poorly in zoos, which is why many, such as the Detroit Zoo, the Philadelphia Zoo, and the London Zoo, have decided to stop keeping elephants entirely.  In fact, zoos in India are no longer allowed to keep elephants.5  The Detroit Zoo explained their decision to send their two Asian elephants to a sanctuary thusly: "Just as polar bears don’t thrive in hot climates, Asian elephants should not live in small groups without many acres to roam. They clearly shouldn’t have to suffer winters of the North.”6

Lucy at the Edmonton Valley Zoo in the snow.

Like Lucy at the Edmonton Valley Zoo, elephants in captivity suffer from stress and obesity and exhibit numerous psychological problems. 

A survey comparing the records of 4,500 African elephants both in the wild and in captivity found that the median lifespan of a wild elephant is 56 years; the median lifespan of a captive elephant, just 16.9.  Asian elephants appeared to fare even worse, suffering higher rates of infant mortality than their African relatives.  The researchers suggested that stress and obesity are the main culprits of these early deaths, concluding that “bringing elephants into zoos profoundly impairs their viability.”7  Obesity is indeed a major problem for zoo elephants, as are foot infections, and both stem from the same cause: even the largest exhibit cannot possibly provide enough space for adequate exercise; as a result, zoo elephants spend most of their time standing on hard dirt or concrete.  Wild elephants, meanwhile, spend about 20 out of every 24 hours on the move, walking up to 35 miles a day. 8  (Learn about Lucy, the lone elephant at the Edmonton Valley Zoo, who has suffered foot infections for years and is thousands of pounds overweight.) 

While more and more zoos continue to close their elephant exhibits, at least one has chosen to expand theirs.  In 2003, the San Diego Zoo captured and imported 11 African elephants from their natural habitat in Swaziland, despite the fact that the species is designated "vulnerable" by the International Union for the Conservation of Nature9, leaving only 36 elephants in the whole country.  Experts working with the Amboseli Elephant Research Project, the longest running study of wild elephants in the world, decried the decision, stating that “Taking elephants from the wild is not only traumatic for them, it is also detrimental to their health. ... No matter how well your zoo may treat the elephants, your visitors would not want to know what those tranquil elephants went through to make it possible for them to be viewed in captivity.”10 (Do zoos help conserve elephants?)

Chimpanzee sitting on an overturned tire in a barren enclosure

Many primates, like chimpanzees, suffer considerably in zoos, engaging in self-mutilation, endless rocking, and eating of feces.

Primates suffer considerably in zoos, with three-quarters of them dying within the first 20 months of captivity.11  According to chimpanzee expert Jane Goodall, more than half of the world's zoos are "still in bad conditions" and not treating their chimpanzees well.  Even the best of zoos appear unable to compensate for the stress of captivity; in 2011, researchers from the University of Kent studied socially-housed chimpanzees in some of the best zoos in the United States and the United Kingdom and found ample evidence of compromised mental health: endemic behavioural abnormalities, such as self-mutilation, endless rocking, and the eating of feces.  One of the researchers, Dr. Nicholas Newton-Fisher, suggested captivity itself was the deciding factor when it came to their mental health, as behavioural abnormalities persisted even when zoos attempted to create a more natural life; e.g., unpredictable feeding schedules and foraging opportunities, as well as opportunities to socialize.12

"Surplus" animals

Dumping animals is the big, respectable zoos' dirty little secret.--Richard Farinato, head of captive wildlife protection for HSUS13

As a business, a zoo must make money--and nothing brings in money like baby animals.  Animals which cannot reproduce either because of age or health are considered "surplus". (An exception exists for animals who are useful when it comes to raising young; for example, a gorilla "aunt.")14 Knut, a baby polar bear born in December of 2006, is estimated to be the biggest money-making animal of all time: by his first birthday he had been nicknamed the "Milliobear" by economy watchers, for bringing in between as much as 11 million dollars to the Berlin Zoo and by boosting their visitor count by 30%--the most successful year for the zoo since it first opened in 1844.  His official logo was used to sell plush animals, t-shirts, books, porcelain collector's plates, candy, credit cards, ice scrapers, sofas, cell phone ringtones, and engine oil, among dozens of other products. 15  He was on the cover of Vanity Fair, inspired several popular German songs, and even starred in a feature film.  When the zoo registered "Knut" as a trademark, the value of its stock shares went from €2,000 to €4,820 in one week.16

Knut on cover of German Vanity Fair.

Knut, a baby polar bear at the Berlin Zoo, was estimated to be the biggest money-making animal of all time.

By July of 2007, however, Knut was seven months old and large enough that he had to be separated from the keeper who had raised him, and the twice-daily performances, in which he and the keeper would play in front of crowds of zoo visitors, were cancelled.  Knut was nearly sold to another zoo, but Berliners were distraught at the thought of losing their city's "mascot", and the decision was reversed.  Meanwhile, the zoo made plans to promote another baby animal: Ernst, a newborn Malay Bear.17  Less than a year later, Knut died as a result of a brain disease.

When babies are born, bringing in legions of new customers, it is the older, less popular animals that pay the price. They frequently end up in decrepit roadside zoos or travelling circuses, in slaughterhouses, as backyard pets, or even on shooting ranges and hunting ranches.  The Association of Zoos and Aquariums insists that member zoos adhere to a strict ethics code which restricts the transfer of animals only to other accredited zoos or unaccredited zoos which have shown the "expertise, records management capabilities, financial stability, and facilities required to properly care" for them. (What does accreditation really mean?) Despite this, an investigation revealed that of the 19,361 mammals that left accredited zoos between 1992 and 1998, 38% went to dealers, auctions, substandard unaccredited roadside zoos, hunting ranches, game farms, and private owners.18  Another study, conducted in 2002, showed the same results: many of the leading member zoos were shipping mammals and exotic birds to roadside facilities below AZA standards, as well as providing animals to dealers who reportedly sold to hunting ranches, auctions, and private owners.19

The problem of what to do with "surplus" animals exists all over the world. The Berlin Zoo, where Knut was born, was accused of misconduct in 2008 after hundreds of its animals disappeared without explanation.  Four asiatic black bears and a pygmy hippopotamus were supposed to have been shipped to a zoo in Wortel, Belgium, which doesn't have a zoo but does have a slaughterhouse.  (An undercover video later surfaced of a tiger, allegedly from different German zoo, being sliced apart at the Wortel slaughterhouse.)20  Multiple lions and panthers were also sent to China, allegedly to be ground up for potency-boosting drugs.21  And in 2014, the Copenhagen Zoo made international headlines when it slaughtered a healthy young giraffe, Marius, with a bolt gun, and dissected his body in front of a crowd of visitors as an educational event. A spokesperson from the European Association of Zoos and Aquariums explained that the slaughter was necessary because, as Marius's parents had already produced other offspring, "he [could] not add anything further to the breeding programme that does not already exist." 22 Just one month later, the same zoo slaughtered two lion cubs and two older males to make space for a new, younger male.23

Red River Hog piglets at Cincinnati Zoo.

Even endangered animals, like these Red River Hog piglets, are sometimes considered surplus and killed. (Photo: Ltshears, Wikimedia Commons)

Even rare and endangered animals can deemed "surplus".  The Edinburgh Zoo in Scotland came under fire when it was revealed that it had euthanized two endangered Red River Hog piglets in 2009--the first born in the history of the zoo--as they were considered "surplus to requirement" under the rules of the European Endangered Species Breeding Programme.24 Despite this, the zoo bred the two adult hogs, Belle and Hamish, again in 2011 and were considering euthanizing the three resulting piglets.  An immediate public protest saved them.25 One zoo insider was quoted as saying "Many zoos and animal organisations around the world adhere to the breeding programme and more animals are put down than you think...you have to wonder why three healthy animals can’t be rehomed and if the zoo know there’s a good chance they’ll have to be killed, why let them breed in the first place? It is not something all staff agree with.”26 Meanwhile, the Edinburgh Zoo confirmed that they would continue to "allow" Belle and Hamish to breed.27

Tiger skin rug

A live zoo tiger is nearly worthless, but a dead one can bring $10,000 or more. (Photo: WSPA)

Lions and tigers are frequent victims of the "surplus" animal trade.  The methods through which zoos rid themselves of extra animals has resulted in a market so saturated that a tiger cub may be purchased for a few hundred dollars, and a live adult tiger is nearly worthless.  A dead one is a different story, however; in 2002 seven people were arrested in Chicago when authorities found that they had killed seventeen tigers and one leopard for skin, skulls, meat, and other various body parts, which can be worth $10,000 or more per animal.28  Undercover investigators in England were offered the skins of two zoo tigers for £6,000.  Both animals were only a few years old when they died.  The taxidermist stated that there were "too many of them" and zoos, recognizing a market for their stuffed bodies, were placing a "shelf life" on tigers and killing them before they became old or ill and began to cost more money than they brought in.29  In the United States, lion meat is legally available for purchase even while wild populations of lions continue to struggle, and while the origin of the meat is shady at best, an investigation conducted in 2010 revealed lion cubs being bred for the captive display industry and caged lions being shot at the slaughterhouse.  Similarly, Czimer's Game and Seafood in Illinois was convicted in 2003 of selling the skinned carcasses of sixteen tigers, four lions, and two cougars as "lion meat" for more than $38,000.30

Big cats also end up on the shooting range; hunters prefer to kill lions from zoos because their manes are cleaner than those of wild lions, making them better trophies.31  Other animals are sent off for canned hunts as well.  Buddy Jordan, former board member of the San Antonio Zoo and secretary-treasurer to a Texas-based hunting lobby, has been implicated in numerous scandals over the past two decades as a result of selling multiple exotic animals, many of them endangered, to auctions connected to hunting ranches and canned-hunt suppliers.  In 1996 and 1997 alone, Jordan received about one hundred surplus animals from zoos, including gazelles, Eld's deer, ruffed lemurs, impala, a ring-tailed lemur, and a siamang.  32 Zoos still continue to sell animals to Jordan; in 2008, Missouri's Dickerson Park Zoo transferred giraffes, red kangaroos, a red-necked wallaby, and a greater kudu to his property. 33


Roadside Zoos

Tiger in a small, dirty cage.

Many animals in roadside zoos, like this tiger, live in small, poorly-constructed cages with concrete floors.

Roadside zoos are unaccredited, but they are one of many places where accredited zoos send their surplus animals.  In most provinces of Canada, people who decide to open a roadside zoo are not required to have any practical experience in zoo management or animal husbandry, and it shows: recent inspections at roadside zoos across the country have revealed animals languishing in filthy, poorly-constructed cages filled with feces and garbage.  Water bowls were often empty, food was species-inappropriate and sometimes even rotten.34  (Tigers and other big cats, for example, are sometimes fed a cheap, all-poultry diet, resulting in metabolic bone disease that can cause their legs to break.)35  

Bald eagle in a small cage.

In the wild, bald eagles regularly fly at heights of over 10,000 feet. (Photo: Jo-Anne McArthur, We Animals)

Many animals were housed in conditions which were completely inappropriate for their species.  Birds were not given space to fly, and other animals had no space to run.  Solitary animals were housed in groups while social animals were kept alone.  Floors were often concrete or wire, even for animals who dig burrows in the wild. 36 In a 2002 study conducted in Ontario, independent zoo consultants Karen Cowan and Jennifer L. Long documented animals with stereotypies and behavioural problems at fourteen of the sixteen roadside zoos they visited.37

Some roadside zoos even attempt to gain legitimacy--and extra income--by declaring themselves "sanctuaries" or "preserves", garnering donations from a well-meaning public by declaring that they are saving endangered species.  Real sanctuaries neither breed nor sell their animals, but roadside zoos do: they are one of the major reasons that there are an estimated 10,000 hybrid tigers living in North America. Hybrid animals have no value insofar as conservation of the species is concerned, and many of them are inbred, resulting in painful physical problems.3839  


How safe are zoos?

As demonstrated by the aquarium industry, working with large, wild animals can be dangerous.  This is a list of just a few of the many injuries and deaths that have occurred at zoos in the last few years alone:

  • At the London Zoo in 2001, a zoo keeper was trampled and killed by a female elephant after falling into the paddock; it was the third such incident in Britain in just three years.40    
  • In 2002, a zoo keeper at Busch Gardens in Florida had her arm torn off by a lion during a routine training exercise.41
  • Also in 2002, a keeper was killed by a mother elephant at the Pittsburgh Zoo, who knocked him to the ground, pinned him down, and crushed him with her head.42
  • In 2007, a worker at the Denver Zoo was mauled by a jaguar and died from a broken neck; the jaguar was shot and killed during the rescue attempt.43  
  • That same year, a zoo keeper at the San Antonio Zoo was critically injured in a tiger attack.44 
  • In January 2011, two chimpanzees attacked a zoo keeper at the Riverside Discovery Center in Nebraska, biting off two of her fingers.45
  • That same month, a trainer at the Knoxville Zoo in Tennessee was killed when Edie, an elephant, backed up and crushed her against a stall; unlike most elephant-related zoo deaths, it was determined to be an accident and not an attack.46
  • In August 2012, a tiger at the Cologne Zoo in Germany escaped his enclosure after the gate was closed improperly, made his way to a nearby storage building and killed a zoo keeper. The tiger was shot dead before he could enter the visitors' area.47
  • In October 2012, a keeper at the Taronga Zoo in Australia was seriously injured when an elephant pinned her against a post during a routine training session.48

It isn't just zoo employees who are at risk of attack:

  •  In December 2007, Jabari, a 300 pound gorilla at the Dallas Zoo, escaped from his cage and attacked four people, including a three-year-old boy.  The boy was bitten multiple times on his head and chest and he and his mother were thrown against a wall.  Jabari also bit another woman's arm several times as she tried to protect a group of children, then roamed the zoo for 40 minutes before being shot and killed by police.   Zoo director Rich Buickerood was baffled by the escape, describing the gorilla enclosure as "one of the best in the country."49
  • Later that month at the San Francisco Zoo, a Siberian tiger named Tatiana leapt over the wall of her enclosure to maul three teenage boys who had been "teasing" her.  One, Carlos Sousa Jr., was killed, and Tatiana was shot to death.  It was later revealed that despite the initial reports of zoo officials, the wall of the enclosure was only 12.5 feet tall, a full four feet short of the national recommendation.50 Tatiana had also attacked a zoo keeper during a "routine public feeding" just one year earlier, reaching through the bars of her cage to maul her arm.51  
  • In July 2012, five chimpanzees escaped at the Hanover Zoo in Germany by using branches as a makeshift ladder to climb out of their fenced-in enclosure. One knocked over a five-year-old girl, causing head lacerations and bruising.52 
  • In November 2012, a two-year-old boy at the Pittsburgh Zoo was killed by endangered African wild dogs when he fell into their enclosure after his mother attempted to balance him on the railing. He fell into a net placed below the railing initially but bounced out, and was attacked immediately. One of the dogs was shot and killed by police.53  It was not the first such incident at that exhibit; that spring, nine of the dogs had managed to dig their way out of their enclosure.  They ended up in a "backup" enclosure and, after the approximately 200 visitors were moved into nearby buildings for safety, the dogs were corralled by staff.54

Are zoos and aquariums educational?

There is no compelling evidence to date that zoos and aquariums promote attitude changes, education, or interest in conservation in their visitors, despite claims to the contrary. --Lori Marino, neuroscientist at Emory University and specialist in dolphin and whale intelligence55

Captivity for educational purposes is actually a relatively new concept in the world of zoos and aquariums, which until the mid-1980s were devoted almost entirely to entertainment.  By then the public's growing interest in environmentalism and animal welfare had become a threat to the industry, as had increasingly persuasive arguments against captivity.  High mortality rates at zoos and aquariums, coupled with numerous accidents and injuries--to both humans and animals--did not help.  When parks responded, they did so quickly, presenting themselves as leaders in conservation and education with entertainment on the side.  Not everybody in the industry agreed with these tactics, however:

Sea World was created strictly as entertainment.  We didn't try to wear this false facade of educational significance. --George Millay, founder of Sea World, 198956

Even when educational information is provided to guests, it omits certain facts in order to present captivity in the best light possible.  The Indianapolis Zoo's website stated that the average lifespan of wild bottlenose dolphins was 37 years of age until a newspaper reporter pointed out that none of the aquarium's dolphins had lived past 21. The information on the website changed to follow suit: suddenly, the life expectancy of wild bottlenose dolphins was listed as only 17 years.57  Meanwhile, field researchers maintain that male wild orcas live an average of 29 years and sometimes into their 60s, while females live an average of 50 years and sometimes into their 80s--but aquariums don't agree.58  In one of their educational booklets in 1991, Marineland of Ontario stated that wild orcas live about 50 years, but by 1995, the booklets claimed that they only lived 35 years.  A Sea World book for children insisted that orcas lived an average of 25 to 35 years, describing the conclusions of field researchers as "pure speculation". 59  (Meanwhile, a 103 year old female orca was spotted off the coast of British Columbia in 2014.)60The famous "droopy dorsal fin" seen almost exclusively in captive orcas was described in a 1995 pre-performance "Killer Whale Quiz" at one of Sea World's orca shows as a genetic trait,  like the colour of one's eyes or hair.61 

Lone Macaw at Canadian Zoo.

The sign by this cage at a Canadian zoo informs visitors that "Macaws mate for life..." This one, however, lives alone in a nearly barren enclosure. (Photo: Jo-Anne McArthur, We Animals)

Despite outwardly confident claims of educational value, even the American Association of Zoos and Aquariums admits that while there "...is some evidence of zoo experiences resulting in changes in visitors’ intention to act, there are few studies demonstrating actual changes in behavior."  Existing studies, however, indicate that  zoos and aquariums do little to increase the public's knowledge of animals and of conservation-related issues.

Over a period of 5 summers, National Zoo curator Dale Marcellini followed 7000 guests and found that “it didn’t matter what was on display … people [were] treating the exhibits like wallpaper” and recommended that “officials should stop kidding themselves about the tremendous educational value of showing an animal behind a glass wall.”62   Another study, conducted by Zoocheck Canada at the Toronto Zoo, watched visitors at seven different exhibits, including the elephants.  Researchers found that the visitors spent an average of 117 seconds per exhibit, with a mean time of just 79.5 seconds, and of those who looked at the elephant exhibit, less than 1% read the signage.  A study conducted at the Chester Zoo in the UK revealed similar results; on average, people were spending less than two minutes per exhibit.63

Elephant study chart.

Zoocheck's study found that visitors spent less than 2 minutes looking at elephants at the Toronto Zoo

In 2007, the AZA attempted to prove otherwise with a survey, asking park visitors to agree or disagree with statements such as “Animals are amazing”,  “I am part of the solution to nature’s problems" and “Being at the zoo/aquarium is fun.”  The resulting study was not peer-reviewed and claimed that about 10% of park visitors had increased their knowledge in regards to conservation-based matters, and that 5% were spurred to increase their "conservation-related behaviour".  Over time, only 20% to 40% of visitors could even remember specific exhibits or animals that they had seen. The study did not delve into whether they had changed their behaviour as a result of their visit.64 However, a critical evaluation of the AZA study was published in the peer-reviewed journal Society and Animals in 2010.  Authored by neuroscientist Lori Marino, the evaluation declared it to be "so methodologically flawed as to be un-interpretable at best"65, noting that it assessed only what survey respondents said they believed or understood, but did not administer any direct measures of knowledge about animals or conservation. Marino and her co-authors found "at least" six major weaknesses that compromised the validity of the study. For example, the non-random sampling of survey respondents were informed “fully and accurately of the purpose of the study" and assured that by participating, they would be providing "positive and tangible benefits to future zoo or aquarium visitors"; they were also given small gifts.66

Beluga in tank while child ignores her.

Vancouver Aquarium, 2009. Studies have shown that on average, people spend less than 2 minutes looking at live animal exhibits. (Photo: Jo-Anne McArthur, We Animals)

Another study in Europe compared two groups of students after they took a lesson on marine mammals, evaluating their levels of knowledge after the lesson at intervals of one day, two weeks, and three months.  One group went to an aquarium, and the other learned about them in the classroom, and though the aquarium-taught students scored higher after one day and after two weeks, by the three month interval both groups of students were scoring similarly.67  Since zoos and aquariums are not set up as educational centres, it should not be surprising that people do not retain much of the information garnered from visits. 

Studies have shown that interactive exhibits are superior not only when it comes to learning but to retaining information.  Rather than passively viewing a captive animal, interactive exhibits allow people to learn by building on their own experiences.  Zoos and aquariums are well aware that captive animals do not accurately represent their wild counterparts.  The Vancouver Aquarium, for example, worked with Steve diPaola, an associate professor of interactive arts and technology professor at Simon Fraser University, to create a virtual beluga pod to supplement the aquarium's current beluga exhibit.  The virtual cetaceans "would be used to show visitors how the whales behave in the wild, something not possible with the captive belugas."  Visitors would have the option of interacting with the pod of virtual whales, introducing variables such as new, aggressive belugas.  And though the technology is not available yet, diPaola hopes that with cameras and sensors, the realtime activity of wild whales could be duplicated by virtual ones: "even though you come to know and love your favourite animal, it's left in the wild so you can see it in real situations, but you have added options like...seeing the situation from different angles, feeling more empathy with the animal because you can observe their heart rate and other data to understand how it feels in particular situations."  He suggests that in time and with appropriate technology, these virtual animals could eliminate the demand for captive ones.  The project is currently on hold.68

The educational benefit of watching a dolphin in captivity would be like learning about humanity only by watching prisoners in solitary confinement.--Jacques Cousteau, explorer, scientist, and pioneer in marine conservation


Conservation and research claims

“There is a commonly held misconception that zoos are not only saving wild animals from extinction but also reintroducing them to their wild habitats. The confusion stems from many sources, all of them zoo-based… In reality, most zoos have had no contact of any kind with any reintroduction program.”--David Hancocks, former zoo director with 30 years' experience69

Fewer than 5% to 10% of zoos, dolphinariums, and aquariums are actually involved in what would qualify as substantial conservation programs either in the wild or in captive settings, and even then, the amount spent on these programs is a "mere fraction" of their overall income.70 A study conducted in 1999 showed that parks belonging to the Association of Zoo and Aquariums donated about one-tenth of 1% of their annual operating budgets on conservation efforts. 71  Sea World, for example, allocated $1.3 million to conservation efforts in 2007--the most generous amount to date--but this is less than 1% of the annual income generated by Sea World Orlando, just one of their three parks.72  And the Los Angeles Zoo spends just 5% of its $17 million annual budget on conservation efforts, while 12% goes to advertising and promotion.73  (It is worth noting that the American Association of Zoos and Aquariums has actually praised the Los Angeles Zoo for being one of the facilities which "spends the most as a percentage of their budget" on conservation initiatives that directly impact animals living in the wild.)74 Meanwhile, it has been recommended that if zoos and aquariums want to make "a serious contribution" towards conservation efforts, they should allocate at least 10% of their operating income to them.75 Because zoos operate chiefly for entertainment purposes, however, it is difficult for them to devote much money to anything else.  

Porcupine with Conservation through Education sign

Contrary to what this sign at the Calgary Zoo implies, few zoos spend even a fraction of their overall income on substantial conservation programs. (Photo: Jo Anne-McArthur, We Animals)

For example, the St. Louis Zoo spent $18 million on a new pool for its sea lions in 2012. Sea lions are not endangered, but they are one of the zoo's most popular attractions.  Meanwhile, plans to provide more space for the breeding of endangered animals and a frozen pond for walruses were shelved in favour of more parking spaces for guests and new restrooms. And while Dr. Jeffrey P. Bonner, president and chief executive of the St. Louis Zoo, insists that the zoo usually uses conservation funds for animals who have a chance of rebounding in the wild, he admitted in 2012 that they spent $20 million dollars, or 40% of the zoo's annual operating budget, to build a new polar bear exhibit.  The zoo's last polar bear died in 2009 and it is illegal to capture (or rescue) the few remaining wild ones, but Dr. Bonner hopes that in the five years it will take for the exhibit to be completed, he will be able to argue for an exemption or buy cubs from another facility.76 

As with the education argument, conservation is a very new concept in the captive animal business, one that developed as a result of the public's growing concerns about animal welfare and the environment.  Most zoos and aquariums do not focus on protecting wild populations, nor do they take active steps to ensure the successful reintroduction of captive animals, both of primary importance; instead, they focus on captive breeding, under the pretense that captive-born animals will eventually be released into the wild.   Experts in conservation describe captive breeding as "a last resort," not a long-term solution, stating that we must focus first on preventing habitat and ecosystem destruction.77  This is frequently not happening, however: in British Columbia, for example, the government approved a captive breeding program for the province's critically endangered Spotted Owl, while allowing logging in the owl's natural habitat to continue.78   

Zoos have painted themselves as saviors of the wild.  I fear this has instilled a false sense of security in the public mind. Many people now believe they don't have to worry about saving animals, because zoos are doing the job. --David Hancocks, former zoo director with 30 years' experience79

Dr. Steven L. Monfort, the director of the Smithsonian Conservation Biology Institute, part of the National Zoo in Washington, has described the current zoo model as "broken", stating that zoos should spend more money on protecting animals in the wild and that more emphasis should be placed on endangered species, rather than popular attractions like sea lions.  He proposes that zoos build facilities large enough to handle whole herds of animals so as to promote more natural reproduction, and that these facilities need not be open to the public. Dr. Monfort has also recommended a complete rehaul of the AZA's accreditation system based on conservation efforts: "I am comfortable with raising the standards for zoos so that eventually it will be harder and harder to be accredited unless you are doing that...if you can’t keep up, then you probably need to be dropped off the bottom."80

African elephants are designated as "vulnerable" by the International Union for Conservation of Nature.   But while many zoos are closing their elephant exhibits out of concern for the animals' welfare, others continue to mislead the public as to the role they play in conserving the species. In 2003, the International Union for Conservation of Nature/Species Survival Commission African Elephant Specialist Group stated that: "The AfESG is concerned by the poor breeding success and low life expectancy of captive African elephants and does not see any contribution to the effective conservation of the species through captive breeding per se."81 In fact, even the zoo industry has stated that they have no intention of returning elephants in North American zoos to the wild;  nor do they believe that doing so would save elephants from extinction. Captive elephants breed very rarely, which is part of the reason that zoos continue to capture wild ones; the North American Regional Studbook for African Elephants (2000) indicates that only 7% of the approximately 206 female elephants in captivity have reproduced at all. In the wild, however, African elephants actually breed readily: the typical female elephant produces about seven offspring during her lifespan, and in some of the very few areas in which elephants are not regularly threatened by capture, poaching, hunting, and the destruction of their habitat, their populations are rising.82 It costs about 50 times more to keep captive elephants than it would to protect the equivalent number of wild ones.  For example, the Amboseli Elephant Research Project, which protects about 52 wild elephant families, or approximately 1,400 elephants, in Kenya, has an annual operating budget of $400,000.  Some zoos spend that amount to maintain just 4 captive elephants for a year.83  

Troop of elephants travelling freely in Africa.

It costs about 50 times more to keep captive elephants as it would to protect the equivalent number of wild ones. (Photo: Amboseli Elephant Research Project)

Historically, attempts at reintroducing threatened species to the wild have been less than successful. Benjamin Beck, former associate director of biological programs at the National Zoo in Washington, D.C, noted that of 145 reintroduction programs carried out over the last century, only 11% achieved any degree of success.  Of those, most were carried out by government agencies, not zoos or aquariums.  Failed attempts were attributed to "improper behaviour" on the part of animals, who were unable to forage, avoid predators, or even interact appropriately with members of their species. 84

The issue of genetic diversity presents additional complications.   One study on the scientific benefit of cetaceans in captivity, for example, suggests that a plan preserving 90% of the genetic diversity of wild populations over 200 years would require "several thousands of animals".85   The captive orca industry has relied almost entirely on one male orca, Tilikum--infamous for being involved with the deaths of three people over the past two decades--to father 10 of the approximately 42 orcas in captivity worldwide.  He also fathered 7 additional pups, all of whom have since died. It appears that Tilikum's unusual breeding success can be attributed to the same issues that have caused him to be violent; he has high testosterone "surges".86  This limited gene pool is a recipe for an inbred population, not a plan for conservation.  And to maintain the genetic diversity of captive polar bears over the course of a century, 200 are needed. Currently there are 64 and, under the Marine Mammal Protection Act, it is illegal to remove additional polar bears from the wild.87 

Furthermore, research has demonstrated that when generations of animals live in captivity, natural selection takes over: heritable genetic characteristics that are favourable to captivity arise, while characteristics favourable to life in the wild are bred out.  According to Dr. Richard Frankham, of Australia's Macquarie University, "Characteristics selected for under-captive conditions are overwhelmingly disadvantageous in the natural environment."  The longer a species stays in captivity, the less chance it has of surviving in the wild.88  

Aquariums and zoos also suggest that the information garnered from captive populations of non-endangered animals, like bottlenose dolphins, might eventually be used to plan captive-breeding methods for endangered ones.  This does not take into account, however, the fact that different species react to captivity in very different ways.89  The Vancouver Aquarium attempted to create an exhibit of narwhals, a species that is "near-threatened" and, among marine mammals, particularly sensitive to climate change90, in 1970.  Though their close cousins, the belugas, can survive in captivity, all six narwhals died within three months of having been caught and attempts by other aquariums have been similarly unsuccessful.91,92  (A baby narwhal was also caught two years prior, in 1968, but was shot as a result of "severe rope cuts" sustained during capture.)93  And Baiji dolphins, now thought to be extinct, are cousins of bottlenose dolphins, but out of six captured for conservation purposes, only one lived for more than two-and-a-half years in captivity.94


What does accreditation really mean?

Primates in small, metal enclosure.

Primates living at the CAZA-certified Assiniboine Park Zoo in Quebec. (Photo: Jo-Anne McArthur, We Animals)

Some facilities in Canada are certified by the Canadian Association of Zoos and Aquariums.  CAZA boasts that they have "played an invaluable role in bringing Canada’s zoos and aquariums to the forefront of international standards of animal care."95  The Vancouver Aquarium is a member, as is the Greater Vancouver Zoo, in Abbotsford.  Only about 25 zoos and aquariums actually qualify for accreditation, which might sound impressive and trustworthy at first.

Closer examination reveals a conflict of interest, however.   CAZA states that it is "headed by professionals who have years of experience in animal care and all other aspects of zoo and aquarium operation", a claim which suggests third-party certification and a lack of bias.96   This is misleading, however; CAZA's president, vice-president, and board of directors consists entirely of representatives from zoos and aquariums--the same zoos and aquariums that CAZA has accredited.  The Vancouver Aquarium's President, John Nightingale, was on the board of directors at least as early as 2005 and as recently as 2009.  He was also Vice-President of CAZA during 2006 and 2007 and President in 2008.97  Current CAZA officials include Robin Hale, chief executive director of the Toronto Zoo, Denise Prefontaine, director of the Edmonton Valley Zoo, Rachel Léger, director of the Biodome de Montreal, and Serge Lussier, game superintendent of African Lion Safari.  The board of directors also includes representatives of the Vancouver Aquarium, the Calgary Zoo, the Saskatoon Zoo, Zoo de Granby, Riverview Park and Zoo, and Zoo Sauvage de St-Félicien.98 In past years, the board has also been staffed by representatives of Marineland of Niagara Falls, Parc Aquarium du Quebec, and the Magnet Hill Zoo, among others.

Examining the individual facilities that have qualified for membership further indicates that CAZA's accreditation standards are not as trustworthy as we'd like to think.  For example, CAZA has certified the aforementioned Marineland, the only accredited aquarium in Canada other than the Vancouver Aquarium. (Learn more about aquariums.) Marineland has been the target of multiple protests for decades.Their whales and dolphins, which are mainly wild-caught, frequently die young and sometimes disappear without explanation.99   At Marineland, seven orcas have died over the last decade; with the exception of one female who lived about 32 years, their average age at death was six.  Two more are missing and presumed dead, as the aquarium refuses to make any comment on their disappearance.  Another orca died shortly after birth.100

Marineland's record with bottlenose dolphins is even less impressive, and was once described as "certainly among the worst of other North American facilities that keep dolphins captive."101  In the four decades since the aquarium opened, 28 dolphins have disappeared just as the orcas have, and are presumed dead.   Another six were seized and released by U.S. authorities when the plane shipping them was forced to the ground during bad weather.  (Marineland imported six more dolphins from Mexico to replace them; all are missing.)102   Dr. Naomi A. Rose, marine mammal scientist and coordinator of all marine mammal programs for the Humane Society of the United States described the Marineland dolphin show as "almost devoid of biological information" and noted that the performance itself "would not meet the minimum professional educational standards required under the (American) Marine Mammal Protection Act."  In her report, she commented that enclosures did not meet the minimum standards for size, and that rust and peeling paint were affecting water quality. Other issues were the "ragged and tattered" appearance of Duke, a bottlenose dolphin who was swimming in circles in a small tank, his eyes half shut, and a strong smell of chlorine in the air.  She also voiced her concerns about Marineland's tendency to separate mother orcas from their calves shortly after birth, despite the fact that in the wild, orca females stay with their offspring for life.  Perhaps most troubling of all was the story of Junior, a young male orca who was apparently held in virtual isolation in a warehouse for four years while Marineland searched for a buyer for him.  With no outside air or access to sunlight, lethargic and "reportedly psychotic," he died in 1994 at the age of 13. 103104 Learn more about Marineland at the Marineland Animal Defense homepage.

Flamingos living in mall.

Flamingos living in a glass case at the West Edmonton Mall, a CAZA-accredited facility. (Photo: Jo-Anne McArthur, We Animals)

Another CAZA-accredited facility is actually run by the West Edmonton Mall.  A number of animals, including sea lions, flamingos, and penguins, live inside the mall, surrounded by stores and shoppers.  Like Marineland, it has been a source of controversy for years, beginning in 1985 when two pairs of young dolphins were captured off the coast of Florida and sold to the mall for a newly-installed marine exhibit.  Before the dolphins even arrived, protests began, citing concerns about mall noise and a lack of space.  Despite this, the four dolphins lived in a chlorinated concrete tank and performed for shoppers four times daily.   By 2003, three of them were dead: Maria, as a result of ingesting coins and other foreign objects that shoppers threw into their tank; Mavis, who simply stopped eating after the death of her third calf; and Gary, from blood poisoning.  All were about 20 years old, decades shy of the expected lifespan of wild dolphins.  Also deceased were all five calves born to the females during this period.105,106

Sea lion performing at the West Edmonton Mall.

The West Edmonton Mall's three sea lions live next to a cinnamon bun kiosk, a Lenscrafters, and the food court. (Photo: Jo-Anne McArthur, We Animals)

The continued confinement of Howard, the last living dolphin, was an additional source of protest and controversy; at one point, the mall was receiving 500 e-mails a day calling for him to be freed.  Mall officials eventually announced plans to transfer him to a different facility, then put the plans on hold as a result of his "frail health."  Despite this, Howard continued to be used in performances until May 2004, when he was "secretly transferred" to another facility in Florida.107,108  He died of a brain hemorrhage one year later.109,110   That year, the mall decided to replace Howard with a sea lion exhibit.  Four sea lions were transferred from a safari park in Scotland, but one, a young female named Roxy, died en route.  Her cause of death was never determined.111

In 2008, the West Edmonton Mall announced a new interactive exhibit which allows shoppers to put on wetsuits and swim with the three living sea lions for $150.  The program, which mall officials have described as a "rebranding" strategy to bring different entertainment into the mall, has been a source of concern due to a lack of appropriate provincial laws that protect both sea lions and swimmers.112  Zoos in Alberta are required to get approval for interactive exhibits from the Ministry of Sustainable Resource Development, but only native or protected species are included under this mandate, which means that the sea lions are entirely exempt.113   

41 stingrays died as a result of too little oxygen

At the CAZA-certified Calgary Zoo, 41 stingrays died over a matter of days due to a lack of dissolved oxygen in their tank.

The Calgary Zoo, another CAZA-accredited facility, is the second largest zoo in Canada and has an infamously dismal track record when it comes to caring for its animals.  In a 2009 article in the Globe and Mail, prominent U.S. biologist Marc Bekoff voiced his concerns about the zoo, saying, "There are animals dying left and right."114  In 2009 alone, an exotic goat accidentally hanged himself when he became tangled in a rope and fell off a log 115, a capybara was crushed and killed by a hydraulic door when an employee "did not follow protocols" 116, and Barika, a western lowland gorilla, was seen pointing a knife at a fellow cagemate after a zookeeper left it in her enclosure.117  In 2008, a baby elephant died from a virus 118 and 41 stingrays died due to a lack of dissolved oxygen in the "touch tank" they were confined to.  Zoo president Clement Lanthier responded to the resulting controversy by saying, "I think we need to be very frank here. Our main expertise is not in fish here at the Calgary Zoo."119,120 In 2007, four western lowland gorillas died 121, as well as a hippo.122

In 2009, increasing pressure caused CAZA and AZA to conduct a new review of the controversial zoo.123   After an investigation, however, CAZA director Bill Peters said, “Yes, there has been a series of unfortunate incidents and they've been looked at and reports have been done in the various occurrences, but is there a pattern? No, I don't think there's a pattern there."124 The zoo did not lose its accreditation, even after their audit revealed that deaths were even more widespread than the public had originally believed.  Two spider monkeys had also died, one crushed by a hydraulic door, and one as a result of frostbite.  Four mule deer were killed when handlers attempted to catch them for veterinary check-ups, and four sugargliders were crushed, either underfoot or by a door.  Multiple bats died after hitting the piano wire that was strung across their exhibit, and woodland caribou and muskox were repeatedlly injured or killed, either because of "exhibit design or interspecies aggression".125

Lucy the elephant alone in a small barn.

Lucy has lived at the CAZA-certified Edmonton Valley Zoo since 1977, mostly alone.  She suffers a myriad of health problems as a result of her confinement. (Photo: Zoocheck)

Another CAZA-certified zoo is the Edmonton Valley Zoo, in Alberta.   Living at this city-run zoo is Lucy, one of the few elephants living alone in a North American zoo.  An Asian Elephant who was taken from Sri Lanka as a baby in 1977, Lucy has been deprived for decades of the social life that is so important to her species, and especially to female elephants.  In nature, elephants live in extensive social networks in immense, complex ecosystems, travelling up to 35 miles a day.126, 127  In captivity, they typically do poorly, nor do they breed well or live long. 128 The tropical climate of Lucy's original home is very different from the cold weather of Alberta, so she is confined to her barren, cement-floored elephant barn about 76% of the time.  It is a space approximately 200,000 times smaller than the smallest "home range" of wild elephants; even her outdoor enclosure is about 60,000 times smaller than it would be in nature.129  Like other captive elephants, Lucy suffers a myriad of medical issues as a result of her confinement.  Veterinarians have confirmed that she has arthritis and frequent foot infections, both of which are common causes of death for captive elephants.  According to zoo records, these problems have existed for decades, all of them created and compounded by the lack of space, the cold, damp weather, and the hard surfaces on which she stands.  (Even her outdoor enclosure consists of hard, packed dirt, with a minimum of vegetation.)  Lucy is also grossly obese, weighing thousands of pounds more than a wild elephant of her age, and suffers respiratory problems and colic.130

Pelicans in a barren zoo enclosure.

Pelicans in their enclosure at the CAZA-certified Edmonton Valley Zoo. (Photo: Jo-Anne McArthur, We Animals)

Activists have been pushing for years to have Lucy moved to an elephant sanctuary, but the city of Edmonton has refused to allow them to bring the case to court.  Alberta's Chief Justice Catherine Fraser, however, came out against the decision, describing the evidence put forward by animal rights groups as "[packing] a powerful punch... What it reveals is a disturbing image of the magnitude, gravity and persistence of Lucy's ongoing health problems and the severity of the suffering she continues to endure from the conditions in which she has been confined. And it also exposes who is responsible for those conditions and that suffering."131

The Greater Vancouver Zoo is also a member of CAZA, despite having been a target of concern for the BC SPCA and the Vancouver Humane Society for years.  A major black mark on the zoo came in the form of Tina, an elephant who had lived there since 1972.  As early as the late 1980s, Tina was diagnosed as being overweight and suffering from debilitating foot problems as a result of the small enclosure in which she was kept, but it wasn't until 2003, after years of campaigning on the part of animal rights activists, that she was moved to the Elephant Sanctuary in Hohenwald, Tennessee.  At the sanctuary her foot troubles slowly began to improve, and then, after almost a year, she died.  She was 34, long before the typical elephant lifespan of 70 years.132

Giraffe at Greater Vancouver Zoo, 2008

A giraffe at the Greater Vancouver Zoo, 2008. Three died there in one year. (Photo: Zoocheck)

The Greater Vancouver Zoo's track record is even worse when it comes to hippopotamuses.  In 1983, two hippos were given access to a frozen outdoor pond incapable of supporting their immense weight; both animals fell through the ice and drowned.  Gertrude and Harvey, two more hippos, died at the zoo in 2004 and 2005 as a result of kidney failure and intestinal problems, both at only half the lifespan of the average captive hippopotamus.  Six months later, the zoo replaced the pair with a baby hippo named Hazina, and in 2006, it was revealed that for almost two years, she had been living alone in a windowless "temporary" shed with concrete flooring and a pool so shallow that she could not even float in it.  Hippos require water to buoy their immense weight and relieve pressure on their joints.  Formal charges were laid against the zoo as a result, the first time a major Canadian zoo had been charged with animal mistreatment.133  (The incident caused the zoo to lose its CAZA certification briefly; it was reinstated in 2008.)  A indoor-outdoor hippopotamus exhibit was completed six months later, and the charges were dropped when the crown counsel decided that it was "no longer in the public interest" to continue the investigation.  The BC SPCA was disappointed, stating that the charges were justified based on Hazina's long-term abuse. 134

In early 2009, four zebras at the Greater Vancouver Zoo died suddenly after two Cape Buffalo were introduced to their enclosure, probably as a result of extertional myopathy, a condition in prey animals brought on by extreme stress.  Cape Buffalo are large and dangerous animals, and though the two species coexist in the wild, putting them in an enclosed space was "a sign of incompetence on the zoo's part."  The zoo did not make the incident public, choosing instead to replace the dead animals with two new zebras.135  

The Greater Vancouver Zoo has had particular trouble keeping their giraffes alive; in 2006, an infant female died eight days after being born,and in 2011, two more died mysteriously. Amryn, four years old, and his mother, Eleah, who was twenty-three, were each found dead in their barn less than one week apart.136  The cause of death has not been determined, though the Vancouver Humane Society noted that as African animals, giraffes are particularly susceptible to cold weather and have been known to die as a result of exposure in the past.137 Jafari, Eleah's mate and Amryn's father, was found dead in his enclosure less than a year later.  He was twelve years old and, according to zoo staff, "completely healthy."138 (The average lifespan of a captive giraffe is twenty-eight.) 

Last updated May 2014

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