What Is Zoochosis & How Do Animals Get It?

Zoos Do More Harm Than Good home

If you’ve ever been to a zoo and seen polar bears swimming in circles compulsively for hours, or seen tigers pacing back and forth endlessly, or elephants swaying back and forth rhythmically, all with a blank look in their eyes, you’ve witnessed an animal suffering from zoochosis. 

There are people who argue that animals are happy in zoos, or are at least content. Are they? Keep reading to learn about zoochosis and what it tells us about the degree to which captive animals suffer.

Read on to discover:

What Is Zoochosis?
What are the Signs of Zoochosis?
What Causes Zoochosis?
Is Zoochosis a Sign of Suffering?
Is Zoochosis a Disease?
How Many Animals Get Zoochosis?
If I Don’t See Signs of Zoochosis, Does That Mean Everything is OK?
How Can We Prevent Zoochosis?


What Is Zoochosis?

Zoochosis is a form of psychosis that develops in animals held captive in zoos. Most often, it manifests in what are called stereotypic behaviors, or stereotypies, which are often monotonous, obsessive, repetitive actions that serve no purpose. Stated plainly, zoochosis is mental anguish made visible by abnormal behavior, and it’s a common indicator of poor welfare.

Animals evolved in the wild, where they could roam freely, interact socially, problem solve, and in general live a rich sensory life. Captivity, whether in zoos, circuses, aquariums, or elsewhere, denies them all of this and more. As a result, animals suffer.

Crucially, stereotypical behaviors do not occur in the wild, but are exclusively seen in animals held in captivity.


What are the Signs of Zoochosis?

Thousands of different species are kept in zoos, and each one has specific physical and psychological needs that can never be met in captivity, even with the best husbandry practices. The most common stereotypies seen in captive animals can depend on species, and individuals, but often include:

  • Pacing 
  • Bar biting
  • Bobbing, weaving and swaying
  • Rocking
  • Self-mutilation
  • Over-grooming
  • Regurgitating and reingesting food


What Causes Zoochosis? 

In short, the answer is captivity. 

Animals in captivity are restricted in countless ways. They live lives of extreme sensory deprivation. We restrict what they can do and with whom they can socialize. We often separate them from their families and friends. We decide with whom they can mate, or deny them access to a mate entirely and artificially inseminate them using sexually abusive and invasive procedures. We limit their movements, their behaviors, their decision to have offspring, and their ability to fully realize their higher order needs, such as the desire to live autonomously, to make decisions, to do meaningful work. 

Research has found the effects of captivity so detrimental, it can actually cause physical changes to brain structures, which can alter health and behavior.

When animals are denied the ability to live sensory rich lives, and their experiences are limited to the dullest, most blank canvas, mental illness develops.


Is Zoochosis a Sign of Suffering?


Again, stereotypies are a concerning sign of poor welfare that clearly show us animals’ stress and frustration over not being able to engage in instinctive behaviors. Some facilities have gone so far as to administer antidepressants and antipsychotics to a range of different kinds of animals, but that doesn’t solve the underlying cause of their chronic distress, which is confinement.

Don’t take our word for it,  look for evidence of this in nature. You won’t find it. As already stated, animals in the wild who are able to live full lives do not demonstrate stereotypical behaviors. Animals who live in captivity do.



Is Zoochosis a Disease?


According to Wikipedia, “A disease is a particular abnormal condition that negatively affects the structure or function of all or part of an organism, and that is not due to any immediate external injury.” This definition is inclusive of both bodily and mental disorders. 

That said, zoochosis is not a disease in the sense of an abnormal condition that stems from within, such as from one’s own body getting sick. Zoochosis is instead a disease that stems from outside forces, from the extreme sensory deprivation that zoos and other forms of captivity impose upon animals. 

Zoochosis is a mental disorder that manifests in abnormal, and often unhealthy, physical behaviors. It is largely, though not necessarily exclusively, caused by psychological factors induced by physical captivity and sensory deprivation. 

That said, many animals held captive in zoos are the product of breeding programs that result in inbreeding and loss of genetic diversity. So it is certainly possible that in some cases — though certainly not all — there is a biological component to zoochosis.

How Many Animals Get Zoochosis?

We don’t know.

As with all mental conditions, zoochosis is surely suffered to varying degrees by different individuals in different circumstances. In addition, zoochosis manifests in different ways across different individuals and different species. In some animals it may not be noticed by humans at all. So we cannot determine precisely how many animals in captivity suffer from severe mental illness.

There are 240 zoos in 13 countries accredited by the Association of Zoos and Aquariums, with 217 being in the U.S. alone. Collectively, they confine 800,000 animals from 6,000 different species, and that’s still only part of the picture globally, which doesn’t even account for roadside zoos, private possession, or other settings for captive animals, such as agriculture and research.

Accordingly, it is safe to assume that there are many millions, if not billions, of animals worldwide who are held in captivity and live lives of mental anguish. 



If I Don’t See Signs of Zoochosis, Does That Mean Everything is Okay?


Perhaps you have known someone in your own life who is suffering inside but bottles up all their emotions. Research is clear that this happens in nonhuman animals, too. 

If someone looks sick in a way we recognize, we assume they are not well. But when we see an elephant or a bear in captivity swaying incessantly back and forth, most of us don’t understand how and why they are suffering.

How Can We Prevent Zoochosis?

Do not keep animals in captivity. It is as simple as that. 

If you have to keep the animal locked up to prevent them from escaping, that animal is held captive. 

With the exception of real sanctuaries accredited by the Global Federation of Animal Sanctuaries (GFAS), and cases of urgently needed medical care, it is a safe bet that captive animals everywhere are being held captive for the benefit of their human captors, not the animals themselves, and exceptionally rarely, “for the benefit of the species” at extreme cost to the individuals.

Animals, just like us human animals, want to be free. They do not want to live their lives behind bars any more than we do.

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