Zoo Security

From a study on zoo security:

Among other measures, the scientists recommend not allowing animals to walk freely within the zoo grounds, and ensuring there is a physical barrier marking the zoo boundaries, and preventing individuals from escaping through drains, sewers or any other channels.

Isn’t all that sort of obvious?

Posted on November 29, 2010 at 12:32 PM43 Comments


Winter November 29, 2010 12:45 PM

One of the bad problems in zoos are rats (and zoo keepers) spreading infections between the animals and from humans to animals.

They are a major reason it is very dangerous to return zoo animals into a wild population. A single infected zoo animal let loose in the wild could wipe out the wild population.

And animals getting out of the zoo will almost invariably be killed in a traffic accident. The larger will be shot.

But maybe the security angle was not towards protecting the animals? 😉

mdb November 29, 2010 12:50 PM

Many zoos now cater to letting people get up close and personal with the animals (mainly outside the US). People want and expect this. So if this was targeted at a larger audience (i.e. outside the US), it probably needs to be said.

SnallaBolaget November 29, 2010 12:52 PM

Every security person knows that if you don’t point out the obvious, and to the letter what you need, then it’s not going to be done. And you’ll stand there with lions’n’sh*t running around… 😉

Mike Curran November 29, 2010 12:53 PM

The peacock at my local zoo has always wandered around outside of its pen. I remember seeing it roaming free even 25 years ago, though it was probably a different bird.

MelissaMaps November 29, 2010 12:59 PM

My local “zoo” has only one habitat for non-native animals. The rest are native and in outdoor enclosures. And some of the pathways go over a river where alligators often swim by. These are not “zoo” animals, but between them and the free roaming birds and squirrels the lack of enclosure and the minimal nature of the other enclosures gives you the experience of a very lucky nature walk.

Hasufin November 29, 2010 1:16 PM

The reality is that most barriers at zoos are oriented to keeping people away from the animals, not keeping the animals away from the people. Even those that ARE intended to restrain the animals often do so merely by discouraging. I volunteered at a zoo in which the bears were kept in their paddock by an electric fence which only cycled once every 30 seconds, and the spider monkeys were on an island in a pond which was only 2.5′ deep.

For the most part this isn’t a problem: the majority of the animals will stick around without barriers, because they like the free ride. Once, for example, the roadrunner was accidentally released, and it wasn’t noticed for 45 minutes. By then he could have been over 20 miles away. Was he? No, he was atop the bobcat pen, taunting the felines. On another occasion our 18′ boa constrictor left THROUGH the wall of the enclosure… and two weeks later was found under a porch a few blocks away.

Our biggest issues were always the people who would jump fences and pester the animals; in the four years I volunteered, we never had a dangerous animal escape, but we had numerous situations in which visitors put themselves in danger.

Invasive species, however, are a major problem and should be addressed. Unfortunately, that would often require significant upgrades to paddocks and barriers – bearing in mind that even now many smaller zoos continue to use facilities which are decades, and even in some cases over a century old. Upgrading to appropriate facilities is important for safety, containment, and the health of the animals; but the costs are usually in the millions of dollars; without significant public funding such upgrades will never happen.

Craig Trader November 29, 2010 1:29 PM

The National Zoo in DC (part of the Smithsonian Institute) allows some of the primates to move between different houses via high wires. In theory, the wires are high enough that the primates don’t want to risk falling…

Hasufin November 29, 2010 1:57 PM

On the subjects of freely-roaming creatures and invasive species…

The zoo at which I volunteered had a variety of fowl and birds which were allowed to roam freely: Both exotic and native geese and ducks, chickens, pheasants, peabirds (peacocks are the males, peahens are the females), and turkeys. They were fed regularly and never showed any particular inclination to leave the zoo grounds.

I know that the National zoo also allows Golden Lion Tamarins to roam freely; personally I cannot imagine the nightmare of bringing them in for the winter.

But invasive species are a major issue. Where I volunteered, we believed that our prairie dogs had died in their burrows, but discovered instead that they had found a way out and were breeding; the area now has a prairie dog infestation. And in SE Missouri there is now a breeding Nile monitor population which is believed to descend from a pair released by a private owner.

Thus far, there are relatively few success stories when it comes to invasive species. Prevention is by far the best route, but as I mentioned above even that is rather expensive.

mcb November 29, 2010 2:11 PM

At the Minnesota Zoo they are more worried about native whitetail deer transmitting an endemic brainworm infection to their exotics.

They also refined the meerkat exhibit to reduce the chance visitors can come in contact with the residents. A few years back one of the meerkats bit a child. The parents refused rabies prophylaxis and the perp refused to step forward so the entire population was euthanized so their brains could be tested for the disease.

We do get to walk within the birds and butterflies exhibits and some make an escape bid from time to time, but they are still within the secondary containment of the zoo building. If any of these sensitive flashes of colour make it so far as an exterior door the weather will make quick work of them at least six months of the year.

Otherwise the keepers are prepared to shoot dangerous animals which escape their enclosures…just like in Jurassic Park I guess.

pegr November 29, 2010 2:17 PM

I recently had the fortune of visiting the Sydney Zoo. They had paddocks that visitors had to go through double gates to enter. Inside, they let the ‘roos and emus wander freely. The only rule was “stay on the paved path”.

The roos knew where the paved path was, so they stayed just out of reach. The enus, however, seemed to seek out human interaction. It was quite fun!

(Greetz to Randy, the love lorn emu!)

Bruce Clement November 29, 2010 2:20 PM


I’m sure the tamarinds can go anywhere their roots can carry them.

Their biggest problem would be predation by tamarins so mobility could be a great asset 🙂

Rob November 29, 2010 2:23 PM

From what I understand, peacocks + peahens function as watchbirds after hours at zoos. They are out and about at the Bronx Zoo all the time.

Fedos November 29, 2010 2:29 PM

I was once glared at in a menacing manner by a flamingo at the Roger Williams Park Zoo. I was glad that he was behind a barrier because I feared that he might stalk me through the zoo.

noble_serf November 29, 2010 2:41 PM

At the honolulu zoo in the 90s, there were these big, mean crane like african birds that routinely left their habitat in the “savanna” area. One of them was very territorial and liked a patch of landscaping in the middle of the walkway. You’d be sitting on a bench and he’d pop out of the bushes there and claim his turf. Good times. (also escaped peafowl roamed the area behind our house frequently, nice for the kids, noisy as hell for late sleepers)

uk visa November 29, 2010 3:02 PM

I remember being told how the chimpanzees worked out they could earth the electric fences using wet sticks at Chester Zoo, the original zoo without bars. I guess nature abhors barriers almost as much as it abhors vacuums!

BF Skinner November 29, 2010 3:29 PM

“Milwaukee Public Zoo used to allow peacocks to roam freely”

Cleveland City Zoo did the same thing and a more raggedy looking group of birds I never did see. Never let something pretty close to a grubby hand willing to grab.

The Washington National zoo has an exhibit that creeped me out. Orangutan’s have a wire walk way that lets them up out of the enclosure over the walkways and down into another enclosure the think tank. VERY glad that unlike us they don’t throw feces at each other.

helly November 29, 2010 5:24 PM

I recall going to a zoo that had a spider exhibit that was completely exposed to the public. You could reach your hand in and grab one if you were so inclined. I recall this vividly because I thought it was just well cleaned glass and went in for a look. On realizing I was inches away from a good sized spider with nothing between me and it I nearly had a heart attack (spider coward, big ones anyway). I didn’t read the plaque to find out why they stayed in the exhibit.

maelorin November 29, 2010 6:52 PM

there has been a trend towards more ‘natural’ settings, and giving people are more ‘natural’ experience for decades now.

partly to encourage attendance, partly to defuse ‘anti-cruelty’ protests.

like as not, many of the zoos highlighted in this survey moved to an open model without adequate consideration of escape vectors, etc. not uncommon in early adopters of any new fashion to overlook things.

just look at the rush to install millimetre and back scatter x-ray devices in airports.

Tim November 29, 2010 9:17 PM

The Brookfield Zoo near Chicago had Golden Lion Tamarins out and about in a small area this summer (they tend to stay near their food and nest/home, so they did not wander far)–and has done this in the past as well.

Also, there are peafowl roaming around as well.

And in one exhibit, there is nothing between the guests and some Rodrigues Fruit Bats.

Steve Jones November 30, 2010 1:45 AM

Colchester Zoo allows several animals to roam free, including some wild goats that are cute as babies, and people like to feed them. However, when fully grown they are too big and strong to control, have huge horns and sometimes get aggressive. Accident waiting to happen there, as there are often no staff around and even when they try to control them it is difficult.

David Harper November 30, 2010 2:39 AM

Here in England, there are several “safari parks” where animals such as lions and monkeys roam freely, and visitors drive through the park in their own cars.

One is at Longleat, in south-west England between Salisbury and Bristol, and another is at Knowsley, in north-west England, close to Liverpool. There was one at Windsor, near London, but it closed almost 20 years ago.

Visitors are told to remain in their vehicles at all times, and to keep all windows and doors closed. Park rangers are on hand to deal with problems.

It’s like Jurassic Park, but with lions and tigers in place of velociraptors.

mrc November 30, 2010 4:42 AM

I used to work in a theme park which had previously been a zoo/ safari park. Mostly ok But the former hippo pond had several escaped terrapins that lived in it.

Undisclosed November 30, 2010 5:07 AM

@ Bruce Read the theory of evolution before posting. Human think that they are clever but they had forgotten that animals are also living being. They know how to protect themselves. Infact, it applies to every living creature i.e. every living creature have it weapon of protection. Some blind eyes can’t see it or they can see it but their sense of detecting a threat is somewhere else…

Adam November 30, 2010 5:27 AM

I live near Fota wildlife park and most of the non-dangerous animals are free to wander about more or less as they like. Lemurs, capybara, ducks, pelicans, peacocks, spider monkeys, llamas, wallabies etc. Apparently the monkeys have escaped a few times, but mostly they stay put because that’s where the food is.

The dangerous / stampey / bitey animals get large paddocks or islands to live on with single / double wooden or mesh fencing and stone / water barriers as appropriate to their threat to the public.

Pedro Fortuny November 30, 2010 6:02 AM

90% of Engineering is stating and documenting the “obvious”, which is why procedures are so important (they usually state the obvious, which get usually forgotten).

No One November 30, 2010 10:51 AM

@pegr: I remember that enclosure — me and a buddy were stalked by an emu as we made our way through.

I’ve gone through two butterfly enclosures and they both had a heavy fan blowing into the doorway to discourage butterflies from flying out and a double-door where you were reminded to check yourself for hitchhikers.

Peacocks November 30, 2010 11:02 AM

Where I’ve been the peacocks are just ‘kept’ in the same enclosure as large animals, such as a longhorn cow.

Obviously they can fly over the 4′ fence and wander around.

Put a bird in a bird rated cage and he’ll stay put.

Nobody November 30, 2010 9:58 PM

I recall about 8 years ago when I went to Auckland Zoo that the Spider Monkey enclosure was completely unfenced. Instead it was surrounded by a reasonably wide stream that enclosed them in their own little island. Apparently Spider Monkeys are terrified of water so they keep away from it.

I’d imagine this requires work to ensure branches don’t reach over the water to another tree or close to the ground and thus allow them to escape but probably not much more than a fence enclosure with no ‘roof’

Andrew December 1, 2010 7:15 AM

The most dangerous animals at the zoo are primates — the ones who paid admission. They must not be allowed to wander freely, either.

EJ December 1, 2010 7:48 PM


Some zoos (e.g., the San Diego Zoo and Wild Animal Park) also cite that more natural settings are conducive to improving their breeding programs. Most of these use barriers that are less visible to visitors (such as using a trench on the inside of the enclosure before the wall, so the outside of the wall appears lower than it is on the inside of the enclosure) and/or psychologically discouraging to the animals (like angling the fences or walls inwards).

However, as I’ve learned from them: be careful how you fence your tree-climbing goats! (The escapee in question did eventually return on his own… in time for mating season.)

Ian Argent December 16, 2010 2:49 PM

The National Zoo overhead orangutang run it fairly cleverly – I looked at the support masts when I was there over Thanksgiving and noted that the platforms on the masts were designed to discourage leaving the platforms outside the designated “stops”, including electricified guardrails beneath the platform

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