When approached to write an article highlighting zoos and aquariums, I did not hesitate to say yes, as zoos and aquariums have defined my career interests. However, brainstorming has been an overwhelming process, as there are so many directions this article could take. Should it highlight the history of zoos, and how they are evolving from a source of entertainment to a source of education and conservation ? Or emphasize how aspects of husbandry within zoos improve the welfare and health of the animals [2, 3, 4]? Perhaps the article should summarize the different concerns of zoo welfare, and how researchers and zookeepers study zoo animals in order to make their lives (and the lives of their wild counterparts) better [5, 6, 7]. In light of the ongoing, heated debate surrounding animals in captivity, this could be an opportunity to deliberate the topic; to provide readers with information on the pros and cons of zoos and aquariums and leave you all to make your own decisions. However, all of these topics have been extensively reviewed and debated in popular media (some pieces more biased than others), and I decided that there is no need to add more white noise to the debate. So, after reading through scores of articles filled with inflammatory key words, I decided to take a step back, and instead share with you how to navigate through the zoo debate of whether or not we should keep exotic animals in zoos and aquariums.
What’s in a name?
The label “zoo” can stir quite an emotional reaction. To briefly take an interdisciplinary side-step into literature, let’s think about the quote from Shakespeare’s Romeo and Juliet, “What’s in a name? / That which we call a rose / By any other name would smell as sweet.” We can translate this poetic idiom to mean what is important is not the label “zoo”, but the quality of the institution behind it. Zoos and aquariums (henceforth zoos) can be defined as an institution in the United States that houses exotic animal species for public exhibition. However, within this definition there is a spectrum that exists based on a zoo’s mission statement, husbandry management, funding sources, and accreditations, which can (but may not always) correlate to the quality of care and environmental conditions experienced by the animals. The nuanced differences are loaded with history, politics, and economics that could easily be a separate article, so for brevity, here are the basics:
- Funding sources
- Nonprofit zoos: Zoos are eligible for government funding and use a surplus of revenues to promote mission statement objectives (which are commonly conservation and education) rather than divvy additional money to shareholders.
- For-profit zoos: Zoos set their own aims and mission statements, and the purpose of the operations is to earn a profit for shareholders.
- Licensing and Accreditations
- USDA: All animal facilities in the United States are regulated under the US Department of Agriculture. Thus, all zoos must follow federal regulations set by the USDA in order maintain a license and keep their doors open.
- AZA: The Association of Zoos and Aquariums is an independent accreditation organization that zoos can apply for as a “stamp of approval.” AZA is considered the most stringent of regulatory organizations, and has the current highest standards for animal husbandry. In addition to setting zoo management standards, AZA accreditation also requires zoos to have public outreach and education, prioritize animal welfare, and be involved with various conservation projects and initiatives around the world.
- ZAA: The Zoological Association of America is another independent accreditation. ZAA also regulates high standards of zoo management, and the accreditation requires a mission statement that emphasizes conservation and active participation in public outreach and education.
This information is valuable to keep in mind, as the label “zoo” can draw very different pictures in peoples’ minds that influence their opinions. However, taking into consideration the accreditations of each zoo may help form decisions on which organizations to support and visit.
Our Opinions: Emotion, Experience, Knowledge, and Logic Intertwined
Let’s face it – It is rare that people, even researchers, make a decision based solely on logic and facts; instead, opinions are often influenced by emotion [8, 9, 10]. Additionally, we (human and non-human animals) develop views of our world based on our experiences and the emotions tied to those experiences [9, 11]. As someone who defined her career path based on childhood experiences at my local zoo, I have very positive emotions tied to that environment. However, with over ten years of experience as an aquarist, zookeeper, and trainer at several different animal facilities, I now understand the challenges of housing animals in captivity, and recognize the validity of some of the arguments that are often made against zoos.
So, whatever our experiences have been with zoos, or whatever reasoning we use to define our opinion about them, we should recognize two things:
- This topic is not a “black and white” or an “all or nothing” issue. Zoos and aquariums exist on a spectrum, and as with any discussion involving ethics, reasoning is complex and multi-faceted.
- It’s often a very powerful exercise to take a step back and question deep-seated opinions or emotions and where they are stem from.
Let’s Play Devil’s Advocate
Below are some common “pro-” or “anti-” zoo statements that I have either read in other articles or heard firsthand over the years. Whatever side of the argument we come from, it is important to reflect on not only our views, but to reflect upon and recognize the validity of other views.
“I love all zoo animals because I get to be up close and personal with them.”
Yes, the opportunity to see an exotic animal up close may provide some level of inspiration that could cause positive behavioral changes in other parts of our lives. However, do we think that all zoo animals want to be up close and personal with us? While some animals may be habituated to humans, visitor presence can be stressful to animals [12, 13].
One common issue many visitors participate in is knocking on glass or attempting to gain an animal’s attention by vocalizing or making exaggerated movements. These behaviors may elicit an “entertaining” response that can actually be quite bad for the animal’s welfare. Some institutions deal with this issue by stationing docents around high-traffic exhibits to provide educational information and signs that discourage visitors from inadvertently antagonizing animals.
Another preventative solution is using habitat design to mitigate animal stress. Small adjustments such as increasing the viewing distance between visitors and animals or using a one-way mirror viewing area where visitors can observe animals without disturbing them can reduce the likelihood of negative human-animal interactions. Environmental components such as foliage or flowing water can also buffer an animal’s perception of visitor noise volume, high levels of which tend to increase stress . When used strategically, habitat design can also positively influence visitor behavior. For example, when researchers placed a camouflage net over the front of a glass viewing window into a gorilla exhibit, they found that gorillas were less aggressive towards visitors, and that the net led visitors to be quieter and more respectful of the animals (as indicated by the lack of knocking on glass to capture the gorillas’ attention; ). Other research has shown that on busy days, many animals express behaviors related to stress, and make attempts to maintain distance from the public. When animals are given control over their environment by providing opportunities for refuge (e.g. the option to go into an enclosure behind-the-scenes or a human restricted retreat space in petting zoos), many of these negative behaviors are reduced [12, 13].
Thus, shifting perspectives to acknowledge the impact human presence has on zoo animals and recognizing that we are guests in their home is an easy way to improve the experience for both animals and zoo visitors.
“Zoo animals always look sad. They would be much happier in the wild.”
Some questions we should ask ourselves are: Why do we think they look sad? Is it because they are sleeping or inactive? Is it because they are performing abnormal behaviors such as pacing? These are important behaviors that animal welfare scientists and animal caretakers monitor closely because in certain instances, inactivity or abnormal behaviors may be a sign of stress or negative mental state .
Lions taking afternoon snoozes are common in zoos and on the savannah. Sources: Wikipedia Commons and George Hodan
Often, understanding an animal’s natural history helps us understand their behavior in captivity. For example, there are many species that sleep 10 to 14 hours per day in the wild, usually in small increments, and some animals that are crepuscular (most active in the evening or early morning), so day-time naps or periods of inactivity are common for these species . Additionally, many animals go through seasonal changes that coincide with breeding or molting, which may alter their activity levels. Their behavior may not be a result of being “sad”, but the metabolic energy it takes to molt or to prepare for mating season [15, 17].
Additionally, it’s important to consider if these animals be actually be happier in the wild. How we define happiness changes depending on which environment an animal might be “happy” in. Some people think happiness is the freedom to roam and not have to interact with visitors. However, many animals who live in captivity have access to health care, plenty of nutritious food (for example, sea otters eat restaurant-grade shrimp), and are free from predators – all things that are not guaranteed in the wild! While animals can be “happy” in captivity or in the wild, the “happiest” solution for any given animal is difficult to pinpoint and, for those in captivity, depends on differences in ethical standards.
Finally, the “wild” environment is no longer habitable for many species. NOAA’s 2018 global temperature was the hottest year on record, surpassing the previous 5 record-breaking years. This consistent increase in the earth’s temperature has cascading effects on our environment. Animals may be unable to acclimate to these rapidly changing environmental conditions, that may ultimately reduce their population. Aside from climate change, anthropogenic (a.k.a. human-caused) threats such as habitat fragmentation and loss, poaching, pollution, and resource competition (e.g. commercial fishing) present inhospitable environments for animals.
The wild is not always hospitable, and with anthropogenic threats, wild environments can be even more austere.
“Zoo animals shouldn’t be here for our entertainment.”
That is a valid statement. Until the 1970s, menagerie, zoo, and aquarium animals were a source of entertainment for the public, and in the absence of welfare standards, animals often lived in suboptimal environments . As attitudes shifted concerning the roles of zoos, there began an integration of conservation and education principles in the mission statements of zoos. This was followed by drastic improvements in animal care, including more complex, naturalistic habitat structures, nutritionally appropriate diets, and various forms of enrichment [1, 18]. The accepted conclusion by many zoos (especially those that are non-profit or have accreditations rooted with education and conservation mission statements) is that if we were to keep wild animals in captive environments, we have the ethical responsibility to: 1) provide optimal physiological and psychological care for the animals, 2) educate the public on the importance of these species to the wild ecosystem, and 3) capitalize on the opportunity of being up close with these animals to understand more about their behavior and natural history in order to conserve their wild populations .
However, this ethical responsibility is still a work in progress; many private and roadside zoos that keep animals in suboptimal conditions still exist. Thus, it is important that we don’t lump all zoos into one category. In some situations, an optional accreditation won’t incentivize a zoo to change, nor will the morality of providing animals with better living conditions. A possible way to address this issue is by increasing the welfare standards at a policy level and providing resources that would allow for better monitoring of animals in captivity throughout our society.
While their role in entertainment is debated, animals can be a rich source of information. There are many researchers whose sole focus is studying how to improve the lives of animals under human care. There are also many researchers who study animals in the wild, that may collaborate with zoos in order to develop a more detailed understanding of behavior and biology that would otherwise be impossible to understand in wild settings. In fact, this year a scientific review was published highlighting the impact of zoo research contributions. A team of multi-disciplined researchers were tasked with the collection of all population dynamic information known on 32,411 known species of mammals, birds, reptiles, and amphibians. They created a Species Knowledge Index map by collecting animal population dynamics data (e.g. age of sexual maturity, mean number of survived offspring, gestation durations) from 22 databases. After tapping into the Zoological Information Management (ZIMS) System (an information sharing database comprised of 1,200 zoos, aquariums, refuge, research, and education centers), researchers saw an eightfold increase in the amount of information on a variety of species . This shows that zoos have the potential to be untapped sources of information about the natural history, biology, and behavior of animals that can assist in our understanding of our environment as well as aid in conservation planning.
“Zoos provide so much enrichment and food for their animals, of course the animals are happy!”
As mentioned above, some animals in captivity don’t have access to adequate food, medical care, and optimal living environments, much less be given adequate cognitive stimulation and enrichment. Additionally, as we discussed earlier, there are different licenses and accreditations that hold zoos to different management standards. Some focus on basic needs (e.g. food, water, and shelter) while others expand on an animal’s behavioral and cognitive needs (e.g. positive reinforcement training, enrichment). Blanket statements (like the quote above) validate our reasoning for keeping animals under human care, without holding ourselves accountable to investigating if they actually have good welfare. Animal welfare scientists spend their entire careers researching what environmental conditions provide an optimal living environment. Research often includes observing animals, and in some cases “asking” them what features (e.g. habitat design, feeding schedules, enrichment devices, caretaker interactions) they prefer by providing an array of choices for the animals to select . One key thing to remember is that management decisions need to be made based off of an understanding of animal’s biological and behavioral needs, and that it is not beneficial to rely on old husbandry habits or random novelty alone. Strategic planning and active updating of management protocols as new information becomes available is necessary to improving welfare.
“With video technology, there is no need for zoos; just watch them on TV.”
Wildlife documentaries do provide the general public with up-close footage of wild animals in their natural environment. With the calm yet enthusiastic voice of narrators like David Attenborough, it can feel as if we have been transported to a personalized tour of the depths of the Marianas Trench, or under the lush rainforest canopy. However, think about how this footage came to our TV screens. What happened behind the lens to get that shot? While nature shows can be incredibly informative and inspiring, they can also give a false sense of what animals do in the wild, just as much as a poorly constructed zoo habitat. Wildlife filmmakers are the first to admit to the extraordinary patience necessary to wait and follow animals for days, toting massive camera equipment while trying to remain invisible to the animals. Yet the pressure from networks for high ratings and the public push for education disguised as entertainment leads to a sensationalized view of wild animals. While we have moved past Disney’s ethically disastrous 1958 documentary “White Wilderness”, where filmmakers faked a lemming suicide, there are still “tricks of the trade” to get that epic action shot. These include chumming the water to instigate a dramatic shark frenzy, staging predator-prey stand-offs that lead to prey death, or filming detailed shots with animals in captivity.
Aside from the potentially questionable ethics surrounding wildlife filmmaking, increases in technology and media consumption have led society to develop a “nature deficiency.” As renowned biologist and naturalist E.O. Wilson hypothesized, humans possess the innate tendency to seek connections with nature and other forms of life. Biophilia, meaning love of life or living systems, is rooted in our biology, but with technological advancements and urbanization, the ability to connect with nature is becoming more difficult . This disconnect from nature can lead to a disregard for plants and animals around us. For many, zoos and aquariums may be one of the few places where people come into contact with nature and wildlife. While local parks, beaches, and forests may provide access to natural areas, people generally need to make active decisions to learn about and understand their local ecosystems rather than move passively through the environment. Zoos, on the other hand, can make a larger impact by supplying different modes of educational opportunities that facilitate a larger understanding of our global ecosystem, while also tapping into our inner biophilia.
“If people really wanted to see elephants they would just go to Africa.”
Excuse me, but your privilege is showing. Of course, in an ideal world we would all have the ability to travel the world (with no carbon footprint) and learn about new ecosystems, new species, or new cultures! However, while not everyone is able to travel the globe, we all should be able to learn about how our environment is connected at a global level, regardless of income and ability.
Zoos and aquariums that aim to provide education bring the global environment to people who may otherwise not know or not care. In a world that is so connected it is important to help people realize that the decisions they make at grocery stores impact animals in Asia, or that the litter from a person in a landlocked state can make it through the water system and add to the Great Pacific Garbage Patch.
Zoo education can vary from placards, interactive stations, docents stationed at exhibits to answer questions, and zookeepers working with animal ambassadors at public events. Education can also be more in-depth, such as zoo camps, outreach visits to schools, or special events . Observing animals in accredited zoos can enhance the visitors’ connection to nature, understanding of wildlife, and how their actions at a local level affect the environment on a global scale . Connections with a charismatic species or novel ecosystem can be important in making local environmental improvements.
The ethical flipside may be that not all zoo visitors may come to be educated. However, it could be argued that these visitors are the ones that can be highly influenced by a single, good educational interaction. Zoos can debunk myths that sharks are man-eating killers or gorillas are chest-pounding aggressors like King Kong. Zoos can engage visitors long enough to highlight the importance of keeping beaches clean after seeing an ambassador sea turtle who lost his flipper due to marine debris. These experiences can provide a valuable learning experience with positive, long-lasting effects.
Where do we want to go from here?
No matter what our individual opinions about zoos, the rosy-colored glasses of our own view and the large foam fingers that point blame at the other side need to come off in order to have a real discussion on how to provide animals under human care (and in the wild) with better lives. What I’ve taken away from writing this article is that once we take down our opinionated walls, and open up our ears for listening, we realize that most people on either side of the zoo debate have the same goal: happier, healthier, long-lived animals. But what I hope has been demonstrated here is that there is not one hero and one villain, there is no silver-bullet solution, and that nothing is black and white. It is only when we begin to recognize and embrace the gray that we can move forward and actually accomplish our mutual goal of improving the lives of animals.
Karli Chudeau, graduate student in the Animal Behavior Graduate Group and a part of the UC Davis Center for Animal Welfare. She is interested in conservation management and assessing animal welfare in wildlife rehabilitation settings. Her current research examines how we can use behavioral management interventions, such as environmental enrichment, to improve reintroduction success with pinnipeds. She is also an avid ocean nerd.
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