Horizon (1964) s55e06 Episode Script
Should We Close Our Zoos
This programme contains some scenes which some viewers may find upsetting from the start.
'A visit to the zoo has been a staple of family life for more than a century.
' A lot of us will remember the experience of seeing our first wild animal at the zoo as a child.
But is it time that zoos took a long, hard look at what they do? Zoos, if they stay as they are, inevitably will become extinct.
The public will just stop going to them.
I'm Liz Bonnin.
I've studied and worked in zoos, and I've observed just how intelligent animals can be.
Chase and tickle, he wants to chase and tickle with you now.
I want to chase and tickle with you too! But the more science is revealing about animals, the more difficult questions are being raised about why and how animals are kept in zoos.
Why are zoos still keeping elephants now that we know captivity can halve their life expectancy? To us it just became more and more clear that there was no there was no way to really make this work.
We want to be able to sleep at night.
Did captivity drive one of SeaWorld's orcas to kill his trainer? There is no evidence whatsoever that there is any mental aberration that is a result of living in a zoological park.
Why do so many zoo animals exhibit behaviours that are hardly seen in the wild? It does indicate that something is not right.
Is the battle to save endangered animals one that zoos can simply never win? We feel like janitors of the human culture.
We're trying to clean this mess up.
I want to ultimately find out if zoos need to change, to serve animals and humans better.
Or if they should be consigned to history.
A day out at the zoo, in Copenhagen.
In 2014, the zoo offered families an educational experience that some might find disturbing.
A two-year-old giraffe called Marius was culled, then dissected in front of them and fed to the lions.
What happened here lifted the lid on a practice few other zoos embrace so publicly.
Today I'm here to see it happen again.
Copenhagen Zoo has culled another animal.
This time it's a sable antelope.
How was she culled? What method did you use? She was shot with a rifle and you can see, if you want to, that she was shot right in the brain here.
And obviously, this is not a very enjoyable part of our job, but the key here is to do it so the animals have no idea what's coming and it has to be swift and efficient.
The culling of Marius triggered a global storm of protest.
In the firing line was Bengt Holst, director of research at the zoo.
Bengt, were you surprised by the reaction, by the backlash that you got because of the culling of Marius? Yes, very much indeed, and that's because we have done this, we have used this concept for more than 30 years here in the zoo, and we have done it with lions and with bears and leopards and antelopes and a lot of different animals, not with giraffes until now.
But it was really strange because we have never had this reaction before.
It may seem cruel, but culling has come about with the modernisation of zoos.
In the 19th century, when zoos began, most of the animals were taken from the wild.
Zoos would order animals for spring time, you know, because there was a new season and you'd bring them in and if they survived the summer, that was great, but if not, you'd just order some more next year.
Since the 1980s, zoos have aimed to develop a more positive relationship with the natural world.
Today it's much more conservation-minded.
It's ethically wrong to take all animals in from the wild, so we strive at being self-sustaining with as many animals as ever possible.
Now, more than 90% of the animals in zoos are born in captivity.
And around 90% of all species kept are not endangered in the wild.
Animals are carefully paired across zoos around the world to avoid in-breeding and to ensure genetic diversity.
But there is a consequence.
If you want to do serious breeding with animals, where you go for a healthy population far into the future, then you cannot avoid having, at some stage, if they breed well, a surplus.
That's because zoos can't breed just the animals they need to maintain a sustainable population.
You cannot go into a shop and buy three males and four females, for example, if that's what you need for your population.
You have to let them breed and you cannot predict what is the sex ratio.
At Copenhagen, surplus animals are also produced because the zoo takes a particular approach to animal welfare.
This particular animal is considered surplus to the programme, in the sense that her genes are already represented fairly well through numerous of her siblings.
The parents of this antelope, just like Marius's parents, were not paired in the international breeding programme.
Instead, Copenhagen decided to allow them to breed, rather than use methods to stop them, as other zoos do.
Why cull, as opposed to using contraceptives? Because by using contraceptives, you take away the breeding behaviour from the animals.
I think it's very important that we give the animals an opportunity to perform as much natural behaviour as ever possible.
And breeding behaviour is a big part of that natural behaviour.
If you take away that part, you have a welfare problem.
You reduce their welfare.
Before considering culling, zoos look at moving surplus animals to other zoos.
But space is limited, and priority is given to housing animals that are valuable to the breeding programmes.
This sort of proves that there are no surplus animals.
Everything has a role to play.
As controversial as Copenhagen's policy is, perhaps what's most surprising is how openly it's carried out here.
It's not known how many other zoos take the same approach to breeding, but it's estimated that between 3,000-5,000 healthy animals are culled by European zoos every year.
I would say in general, it is actually pretty common, but many zoos are not so open about it.
Some are doing it in disguise.
When Marius the giraffe hit the headlines, Copenhagen says it was criticised by other zoos.
We got attacks from other zoos, also in Europe.
Zoos that practise culling, or? Yes, some zoos that practise culling.
Does this mean that the zoos that were culling, but had attacked you, were saying you shouldn't have made it public, you shouldn't have engaged in the conversation? Some even said that you should have done it without Keep it behind the scenes and then don't mention it at all.
But I think it's not the way forward.
The journey zoos are on from the less-enlightened days of the past has reached a critical point.
The ever-growing human population means the wild has shrunk, with species disappearing faster than ever.
And science has moved on in leaps and bounds in its understanding of animals.
But are zoos adapting with the times? If you peel it all back, and you look at, say, London Zoo in 1828 - and all the other zoos throughout the 19th century - they all had big animals, showy animals, colourful animals, mainly from Africa or from Asia.
The typical zoo today has got exactly the same collections.
They have not moved on from that.
Zoos tell us that the welfare of their animals is at the heart of what they do.
But is it? Zoos have certainly published dozens of scientific papers about their animals.
But all that you can find, all these studies carried out by various zoos around the world, it's not always easy to talk to zoos about some of this research.
So it's hard to judge whether they're really keeping up with the latest scientific insights into animal needs.
At least, in most cases.
There is one zoo that's been quite keen to talk to us about their work and the stickier issues surrounding the welfare of captive animals.
ARCHIVE: 'A day at the zoo.
'The Detroit Zoological Park ranks with the finest in the world.
' Opened in 1928, Detroit Zoo kept the same animals most other zoos did - including elephants, a star attraction.
I've heard people say, "Oh, they haven't got an elephant in that zoo, "can't be any good.
" And if your zoo isn't popular because it doesn't have the animals that the public wants to see, they'll probably have to close the doors.
So we have to educate the public.
I'm visiting the zoo to find out about a novel approach to animal welfare, a vision that's raising a question for all zoos.
This place is taking a long, hard look at the scientific evidence to determine what animals it should keep and what it shouldn't.
The zoo's director, Ron Kagan, wants to show me why, when it came to elephants, he broke with 150 years of zoological tradition.
This used to be the indoor enclosure for Detroit's two Asian elephants.
Now, notice, there is more room for people I was going to say! .
.
than there is for elephants.
I didn't want to be smart about it, but how come there's more room for the people? Because zoos, in the beginning, were thinking a little bit more about people than they were about animals.
When they lived here, both elephants developed arthritis and chronic foot problems.
Many captive elephants have major problems with their feet because they're not walking enough and they're not walking on the right material.
The Michigan climate exacerbated the problem of not giving the elephants enough space.
When we had particularly long, harsh winters, and the elephants had to stay indoors for long periods of time, we knew that wasn't good for them.
To us, it just became more and more clear that there was no way to really make this work.
We want to be able to sleep at night.
In 2004, Detroit announced it was moving its elephants to a sanctuary.
There were people that said, oh, your attendance is going to drop and this is going to hurt revenue and it's going to We said, you know, we don't think that's right.
But we're just not prepared to knowingly keep animals that we don't think are doing well.
At the time, the zoo had just under a million visitors a year.
Now, it gets almost one and a half million.
The reaction from the American Association of Zoos and Aquariums The reaction from the American Association of Zoos and Aquariums who wanted the elephants moved to another zoo was less positive.
I lost my AAZA professional membership.
But what was their explanation for that? The explanation was that I had discussed this publicly.
I'm struggling with that.
Well Why are they so guarded? Because, as is often the case in a profession, people don't like dealing with complex ethical issues in a public forum.
And that was very unsettling for a lot of people in the zoo world.
But Ron was determined to push on with a radical rethink of what a zoo should be.
Instead of going, well, a good zoo must have elephants and rhinos and tigers and lions, you go, a good zoo must have animals that it knows can thrive and it should not have animals that can't thrive.
Detroit Zoo could see their own elephants were not thriving.
But assessing the welfare of captive elephants around the globe requires a more systematic approach.
And that's where science comes in.
Zoos have what are called stud books for most of the animals they keep - records of their genealogical background as well as births, deaths, transfers and imports of animals.
No-one really knew how well the European zoo population of elephants were doing until scientists studied these records.
And what they found was disturbing.
The most significant revelation was how long the elephants in European zoos were living.
It turned out captive-born female Asian elephants - the majority of the zoo population - were living 19 years on average.
Scientists wanted to benchmark this against the wild.
We looked to the nearest thing, which was timber camps in Burma.
And they've got a very good, equivalent stud book for their population.
And we're by no means saying that that is an ideal environment for elephants.
It's hard, they get worked hard.
But even with all that, we find that they were living till they were about 40.
So at least double what we were seeing in zoos.
It really raised a massive red flag that something is not right in the way that zoos are keeping elephants.
The research was published and a backlash began.
From zoos, it was on the whole quite negative and hostile.
And there was a reaction to discrediting us, rather than looking at their practices and the welfare of their elephants so that something could be done about it.
So why are zoos still keeping elephants? It's breakfast time at Twycross Zoo in Warwickshire.
Three of these female Asian elephants were brought here from timber camps in the 1980s.
The latest addition to the herd is two years old.
The zoo's director, Sharon Redrobe, is happy to discuss what the science is revealing about elephants in captivity.
The data is showing that elephants are dying at a much earlier age in captivity in zoos.
So how does one react to that as a zoo director? It's clearly not good enough in zoos at the moment.
The challenge with elephants is that they live, they should live, a very long time.
So any changes we make now won't be seen for 30, 40 years.
But we do know that we used to feed them a lot of cake, for goodness' sake, and they used to get really bad teeth, then they used to get very aggressive and people would shoot them.
This zoo allows the elephants to make choices, rather than directly handling them, as many zoo keepers still do.
According to the science, two risk factors limit the life spans of elephants in captivity - stress and obesity.
What will be really interesting is to see things like, baby Escher when she grows up, will she have arthritis? I really hope not, because we've changed the flooring, we've changed their diets.
So now we don't have fat elephants.
By establishing how elephants are faring in captivity with empirical evidence, scientists have helped to raise the ambition of some zoos.
I think this generation of elephants have suffered, and you can see that in the scientific data.
We can see it.
It's a shame, shame on us.
But the next thing is what we're going to do about it.
And the next generation needs to be protected, and we learn from the past.
The Government has told British zoos they must improve the welfare of their elephants by 2021, or risk having to phase them out.
I think the jury's still out in terms of whether enough will be done, because I think the changes needed are probably so big.
I'm very sceptical as to whether that will happen in this time period.
Science is giving zoos a new tool to help assess the needs of their animals.
A method of determining why animals often behave differently in zoos than in the wild.
Something that was poorly understood by those who first kept animals, like this.
Now, when this was built in the 1920s, it was a really revolutionary kind of big space.
Which is shocking when you think about it, but it was a long time ago.
And in those days, the animals were simply behind bars.
This far from adequate space was home to the zoo's polar bears.
When I've seen some of the early footage, I've seen as many as a dozen polar bears.
Now, the interesting thing to remember - and sometimes people don't know this when they go to zoos - is that obviously there's some animals that are very social, like elephants.
Primates, most primates.
Polar bears are not, so you normally would never see more than two together, except if it's a mother and cubs.
So this must have been a very tricky thing to manage back then.
This overcrowded environment may well have affected the way the polar bears behaved.
I'm sure there was a lot of stereotypy, but nobody was monitoring that or measuring that in the old days.
This is stereotypic behaviour, abnormal and repetitive with no obvious purpose.
Animals still are developing stereotypic behaviour, so it's not just a bygone era.
It's a modern phenomenon that is still an issue.
And I do think it does indicate that something's not right with the environment, and those animals aren't getting what they need.
Stereotypic behaviour is hardly ever seen in the wild, but it's often seen in zoos.
A 2004 Oxford University study reported that around 80% of carnivores performed stereotypic behaviour in captivity.
I'm on my way to meet one of the scientists who gathered data on abnormal behaviour in captive animals to find out what the root causes might be.
What she found fundamentally challenged the way zoos keep and manage animals.
This is the Belle Isle Zoo in Detroit, which opened in 1895.
It once housed one of the species most prone to stereotypic behaviour, polar bears.
Ever since she studied zoology, Professor Georgia Mason has been fascinated by stereotypic behaviour.
I was learning all about how animal behaviour has evolved and how evolution has shaped animals to be really efficient.
And then, in captivity, you'd see all this extravagant, wasteful pacing and head bobbing.
These animals should just be relaxing.
This is the life of Riley.
They've got everything they need.
Professor Mason investigated why animals display this behaviour, which many scientists believe is linked to stress and could reflect psychological damage.
It made me think, these things aren't arbitrary.
They're obviously reflecting something about the animal's natural biology, so let's see if we can tell what that is.
Professor Mason compared how much time carnivores in zoos spent pacing with how far they range over time in the wild.
There was a striking correlation.
We found that species that naturally have large home ranges and species that travel a relatively long way each day, they're the ones most at risk of this behaviour in captivity.
The species most at risk was the polar bear, which has the largest home range of all land mammals - sometimes over 250,000 square kilometres.
When Professor Mason came to publish her paper, she challenged zoos to fundamentally improve the way they keep wide-ranging carnivores or phase them out.
That really put the cat amongst the pigeons.
Why do you think it was so incendiary? I actually don't know! Because there's lots of conversations within the zoo community about, strategically, which species should they prioritise? Should it be the endangered ones, should it be the ones it's easiest to keep well? Should it be the ones that most inspire the public? I mean, it's a fascinating debate.
It is.
And as part of that conversation, I would think you should be allowed to say, let's not keep these.
Not because it's impossible to keep them well, but because it requires knowledge that we don't have yet, or resources that could be better spent on something else.
Among the theme parks of Orlando in Florida, one zoological institution is struggling to persuade the public that it's meeting the needs of some of the world's largest animals.
TV NEWS: 'This is SeaWorld.
'The atmosphere is part zoo, part circus.
' SeaWorld has displayed killer whales since 1964, but it's now mired in controversy after a documentary called Blackfish alleged that captivity severely compromises their welfare.
The film Blackfish examined the events leading up to the fatal attack on a trainer by a male orca, here at SeaWorld Orlando.
Like many people, I was moved by what I saw.
The footage and the accounts from ex-trainers were compelling, and SeaWorld chose not to take part in the film.
I went as far as calling for it to be shut down on Twitter.
Now, SeaWorld have decided to talk to me today, and I really want to hear their side of the story.
Can science cut through the heated debate about the welfare of SeaWorld's orcas? Dr Chris Dold is SeaWorld's head vet.
He's going to show me the orca that killed his trainer.
Oh, I think I can see Look at that! So this is Tilikum? So this is Tilikum, right here.
How would you describe Tilikum? The most impressive animal in a zoological park, anywhere.
During a performance in 2010, Tilikum pulled his trainer, Dawn Brancheau, into the pool.
PHONE CALL: Within minutes, she had drowned.
Why do you think Tilikum attacked and killed Dawn? It's a question that's been asked, and in the question right there, it's a mischaracterisation of what happened.
This was not an attack, this was a terrible accident.
And an accident that impacted all of us deeply.
What happened? If it wasn't an attack, what exactly happened? An accident, truly.
One of the things that we work with our whales on is how humans and whales safely interact, right? Tilikum is different from the rest of our group of whales in that those sorts of normal, safe working behaviours were not taught to him.
Did the constraints of captivity contribute to Tilikum's behaviour that day? A 2012 study tracked a wild orca that travelled almost 9,400 kilometres in 42 days, nonstop.
How far can they travel in any one day? We'd see them pass our field camp and then we'd find out, 24 hours later, that they were 100 miles away.
They've gone through millennia of evolution.
Natural selection is what it is.
These animals have to move those distances to stay healthy.
Three trainers have been killed by captive orcas.
Tilikum has been involved in the deaths of two.
One before SeaWorld owned him, as well as the death of a man who entered his pool in Orlando.
According to SeaWorld's records, their orcas have injured trainers 12 times between 1988 and 2009.
This is an animal that ranges 100 miles a day, that travels not only to hunt, that communicates vast distances and is now in captivity.
Could this somehow contribute to a psychosis that leads to an animal killing not one, but two, but three individuals? The key thing is that Tilikum's behaviour - and there is no evidence whatsoever that there is any mental aberration that is a result of living in a zoological park or otherwise.
How do we know, when we don't actually have the research to show that? Is it conjecture, is it opinions? I think it's experiential evidence.
But is experiential good enough? Does any of this not have to rely on strong, empirical, scientific data? I think, over time, deep, empirical evidence will come forward.
Since Dawn Brancheau's death, action by a federal safety agency has stopped SeaWorld's trainers from being in the water during orca shows.
The question of whether killer whales might suffer psychological problems in captivity remains unanswered.
Scientists have investigated the cognitive capacities of dolphins, members of the cetacean family that includes orcas.
So this is one of the dolphins in front of the mirror, and you can see he's doing something called contingency checking.
He's making strange motions with his head to see if the image in the mirror is doing the same thing, and once he figures out that that's him in the mirror, then he goes on to use the mirror to explore himself in a lot of different ways.
So here's one example of that.
What do I look like upside down? It's a beautiful thing to watch.
And here's another dolphin fooled into believing that he has been given a mark under his pectoral fin and he's actually moving in a way in front of the reflective surface to see if there is an actual mark there.
It's extraordinary behaviour, it's compelling behaviour.
What this research tells us is that these beings have a sense of self.
They have a sense of who they are, what they look like and what their circumstances are.
So they know it was them yesterday, it's them today in the mirror, and it will be them tomorrow.
But science has yet to determine whether animals with complex cognitive capabilities suffer more, or in fact can adapt well, in captivity.
SeaWorld have their own view.
With the relative intelligence of cetaceans, it's actually, I think, what has allowed them to thrive so well in zoological settings.
And that's because, unlike some species of animals that just want to be by themselves and want nothing to do with humans, cetaceans clearly work readily with us.
And that's why we're able to provide such remarkable care for them.
The welfare of SeaWorld's orcas is under scrutiny like never before.
The California Coastal Commission approved SeaWorld's multi-million-dollar plan to expand its pools in San Diego.
But only if it stops breeding orcas there.
SeaWorld is challenging the ruling.
Do you envisage a time in the future where, with scientific evidence, you will choose not to keep killer whales in captivity any more? And keep other animals that have been shown to thrive through hard, empirical data? No.
I don't imagine that future, because we know our killer whales are thriving in the habitats where we keep them now.
SeaWorld has published a paper showing their orcas Iive as long as those in the wild.
Independent scientists are working on rebuttals, due to concerns about the methodology they used.
We've sort of reached the point where we just conclude as a society that there are no solid data that they can thrive in captivity.
It's all hand-waving from SeaWorld.
And so, we need to conclude that this isn't appropriate any more.
This is a species that isn't suitable for a zoo life.
Detroit Zoo believes it's found a way to enable its polar bears to thrive, but it's come at a hefty price.
They call it the Arctic Ring of Life - now home to just two polar bears, a male and a female.
At over 1.
6 acres, this enclosure is more than eight times the size of the old one.
But that's not its only key feature.
We believe the bears have to have some choices.
Yeah.
The habitat was designed There are two separate habitats, so they have opportunities to choose to be with another bear or without another bear.
Choice is an important part of a polar bear's natural behaviour as it moves around in the wild.
They're making lots of decisions.
They're choosing where to be based on prey abundance, mate availability, that kind of thing.
So it could be that really the solution for these animals in zoos is to allow them to make more decisions, give them more control, give them more day to day variability.
So rather than thinking, oh, no, we have to give them giant enclosures, the solutions could be more imaginative.
You see how the hill goes up? Yeah.
For bears, one of their most important senses to them is their sense of smell.
And so there's nothing blocking the wind when they go to the top of the exhibit.
According to a 2013 study by three American zoos, polar bears with stimulating environments and a view out of the enclosure show significantly less stereotypic behaviour.
Detroit Zoo say they see less stereotypic behaviour with their bears here than in their old enclosure.
This hasn't been quantified yet, but it is encouraging, considering animals like these are not suitable for release back into the wild.
It's highly unlikely they could survive.
So what can we say about the lives of these polar bears now? I would say, I believe she has a pretty good life.
That is so subjective.
That's just me.
I 've known her since she was born and I could be totally wrong.
But I believe she has the things that are meaningful.
This enclosure cost around $16 million to design and build.
At that kind of price, trying to meet the welfare needs of animals like polar bears forces zoos to make hard choices.
If you want quality, you have to give up on quantity.
You can't do every animal.
You can't have a postage stamp collection and expect to be able to have all the animals thrive.
The emphasis on animals thriving in captivity, not just surviving, may sound obvious, but it could revolutionise the zoo world.
If zoos really did put welfare at the very top, how would zoos be different? Well, you'd have fewer animals in each zoo.
You'd have fewer species in each zoo.
You'd have species in a climate that is appropriate.
And there's no question in my mind, that's where things are going.
I think you'll see fewer zoos with polar bears, fewer zoos with elephants, fewer zoos with gorillas.
And different ones will have different expertise.
And you know, that means that you might have to travel further if you want to go see a particular type of animal.
But there's no reason that every city should have a zoo that each one has zebras, giraffes, elephants, rhinos, etc.
Around zoos, the world is changing.
We're living through an unprecedented mass extinction crisis.
The rapid rise of the human population has dramatically reshaped the natural environment, destroying habitats at an alarming rate.
Dr Jane Goodall has seen how the wild has shrunk since she first studied chimpanzees in Tanzania in 1960.
And, for her, it makes a compelling case for zoos.
If the world is beautiful, and like it was when I went first to Africa, that's where all chimps should be.
But it's not.
I've seen so many places where there's logging coming closer, chimpanzees under threat.
And, quite honestly, when you go to a really good zoo which has a big outside enclosure, then you think, well, actually, if I was a chimp, I'd probably rather be here than out in all these dangerous situations in the wild.
Because of human impacts, species are disappearing at a rate 100 times faster than would be expected.
Zoos are saying that saving animals is their fundamental role.
At about the same time that television and film were taking over from the simple task that zoos had of showing you what a polar bear looks like, zoos then changed their direction and said, we are conservation centres.
This is our primary purpose, is conservation.
If we weren't breeding and maintaining animals, then some of these animals would be going rapidly extinct in the wild, and we wouldn't have this ark principle, this repository of animals, to ever put them back.
This is the role now of zoos.
It's changed radically since the '50s and the '60s, of just show and tell wild animals.
We are now part of the solution.
I don't think this is a sustainable claim for zoos to say that they're conservation centres.
It's a very thin, slender little column that they've built for themselves to stand on.
When it comes to breeding endangered species, zoos have gained vast amounts of expertise and knowledge, thanks to years of dedication.
Take the effort to save the California condor, one of the world's most endangered birds.
I'm keen to help out, but Mike Clark from LA Zoo has got other ideas.
You don't want me to hold the eggs for you? You're not on the permit, the federal permit to touch the eggs.
You have to have a federal permit to handle them? Oh, yeah.
In the 1980s, there were just 22 California condors Ieft in the wild.
The last of the species were brought into a zoo, and the captive breeding programme began.
So this would be egg LA-10-15.
Each egg is closely monitored.
There you go.
Oh, look at that, that's fantastic.
Look at that.
As the chicks are reared, contact with zoo keepers is limited.
This is a condor hand puppet, something we make right here.
The hand-reared chicks are fed by puppets.
Some birds showed no fear of humans when they were released, so the keepers had to adapt.
So what would this puppet do, other than just drop the food? The chicks can get kind of rambunctious and become abusive towards the puppet, because there's no consequences.
And so the puppet would actually have to move them away, Iike, you're not going to do that, that's not the way to behave.
Over three decades, zoos have perfected the method of breeding condors.
But successfully reintroducing them into the wild is a much greater challenge.
This is Hopper Mountain, north of Los Angeles, one of the sites where captive-born condors are released.
I'm with Estelle Sandhaus, a scientist from Santa Barbara Zoo.
'On the other side of this canyon is a historic nesting site, 'if only I could see it!' Gosh, it's really thrilling to see it.
Yeah, absolutely, absolutely.
God, she's gorgeous, isn't she? Yeah, she absolutely is.
It's amazing.
These mountains have been turned into a zoo of sorts.
The birds are constantly monitored because, without intensive management, the population would once again collapse.
The reason can be found at LA Zoo.
'This is 360, a sick condor brought in from the wild.
' He's a beaut.
'What happened to him reveals just how much human behaviour is 'undermining this reintroduction programme.
' This is a ventral view of the whole body and if you look carefully, you can see a high density object, that's metal, and that is the piece of lead that was poisoning him.
Across the region, hunters often use lead ammunition, which shatters inside the animals they hunt.
As scavengers, condors feed on the carcases and can easily be poisoned.
These are additional radiographs of 360 from June of 2010, June of 2012 and then 2015, like you see here.
So, actually he's been in three times for lead poisoning.
How old is he? Ten.
Ten years old and he's been in three times.
Yeah.
'360 was lucky.
'Vets removed this latest particle, 'but 59 others have died from lead poisoning 'since the reintroduction programme began.
' Look at that wing span.
I mean, there's no question when you see such a spectacular species, of course it should be protected.
Of course we can't let it go extinct, but what's the point of releasing it again if all the threats persist? I think that with these birds out here, we are able to capture people's hearts and minds and really advocate for them and ask folks to change their habits.
After more than 30 years and more than $40 million, there are now 228 California condors in the wild.
With the California condor, zoos have achieved the near impossible.
I mean, it's taken a huge amount of effort and money and intensive, relentless interventions to keep the birds just about alive out here, but the battle they've been fighting for decades now can't be won without changing human behaviour.
This is not just a job to save the species.
This is a human problem and we feel like janitors of the human culture.
We're trying to clean this mess up.
Until the culture changes and the lead is out of their food source, me and the people I work with will be treating leads until we retire, and probably beyond.
When it comes to conservation, British zoos claim that at least 3% of their expenditure goes towards projects in the field.
Figures like this are hard to quantify across the zoo world, but zoos say their conservation role is not just about funding.
We can use animals as ambassadors, we can use them for education and that's really important.
We have half a million people a year seeing these elephants and that's our opportunity to hook them into valuing them, seeing what they're like for real, smelling them, which you don't get from the TV, and then valuing wildlife is how we're going to change the future, cos it's this generation of humans that needs to change their behaviour to save the wild.
The goal of zoos to educate the public about the importance of conservation is laudable, but so far, their success has not been scientifically proven.
The claim that seeing elephants in the zoo will turn you into a conservationist is a completely false claim.
There's no evidence at all that seeing animals in zoos changes people's opinion.
As our cities continue to grow, along with our insatiable consumption of the planet's resources, the destruction of wild habitats is speeding up.
Surveying this seemingly unstoppable tide is conservation scientist Dr Sarah Bexell.
As a veteran of captive breeding programmes, she has strong personal views.
I definitely for a long time have been worried that we are sending the wrong message to the general public, that you can drive your SUV and you can have as many children as you want.
Don't worry, we'll save a couple of the cute ones for you.
Science is going to save the animals we deem worthy of saving.
For the past 25 years, Sarah has worked on some of the world's biggest reintroduction programmes - the golden lion tamarin in Brazil, the black-footed ferret in the American West, the giant panda programme in China.
Like others, this project is succeeding in breeding animals, but struggling to build a self-sustaining population in the wild.
Around 400 pandas have been bred in captivity, but just five have been released and only three survive.
All things considered, a huge amount of money has been spent on the captive breeding programme for pandas and considering so few, although precious individuals, have been reintroduced, has it been worth it? Is it worth it? Ah.
I mean, we've learned a lot, absolutely.
Filled volumes of journals and textbooks and But we have not made significant headway in terms of conservation.
So, I mean, I guess right now, we would almost have to say it has been quite a failure and even though many of these projects even were considered successful for short periods of time, they've lost ground.
And should we continue them? Right now, I'm feeling no, because I'm really worried that it's sending the wrong message to humanity.
It's giving humanity false hopes.
Captive breeding appeared to be a conservation panacea, promising to curb extinctions and replenish the wild.
But as humanity's destruction of habitat gathers pace, Sarah believes zoos need to level with us about what saving endangered species would really require.
I think we need to be brutally honest with the world, that science is not just going to clean up the mess for you all.
We all have to get behind this, we all have to be a part of the solution.
Perhaps the most controversial of all zoo breeding programmes is that of the northern white rhino.
The effort to save this species from extinction began in the mid-1970s as the persecution of these animals by humans increased dramatically.
No animal is safe from poachers.
There were three more white rhino until a few months ago.
Then poachers butchered them at point blank range to steal their valuable horns.
As northern white rhinos were relentlessly hunted over decades, the future of the species came to depend entirely on the ability of zoos to breed them, and that proved far from easy.
The species is now extinct in the wild and unravelling the reasons why reveals just how many aspects of the breeding programme fell short of expectations.
This is the Dvur Kralove Zoo in the Czech Republic.
I'm here to see a very special animal.
This is Nabire.
'Nabire is one of the last five northern white rhinos on Earth.
' Can we say hello, with an apple? Moment.
Little bit back, no.
Yeah, pull everything back.
She might chew on my cuff.
Take it like this.
Just like that? OK, so not flat hand.
OK, put that inside.
OK, I can put that inside.
I can give you an apple, beauty.
Oh, OK, here we go.
Perfect.
Here we go.
Ohhh! HE SPEAKS CZECH Nabire is of breeding age, but unfortunately she's now infertile.
The history of the captive population is a story of extinction taking place in slow motion.
Since 1975, when northern white rhinos were first brought to this zoo, just four calves had been born in captivity.
For many years, the zoo didn't know how to maximise the chances of breeding.
We started to understand if you have, you know, all the animals at one place for a long time, it somehow blocks the, let's say, breeding appetites.
As they failed to breed, the female rhinos were becoming infertile.
When there were just two fertile females left, a decision was made to attempt artificial insemination.
All our hope is on her and we will try to get her pregnant as soon as possible.
But the attempt failed.
Failing with the artificial insemination doesn't mean the programme failed.
We were quite optimistic that we would achieve a pregnancy over time, if we would get full support for such assist reproduction programme.
The zoo devised a new strategy.
The last two fertile females were sent to the Ol Pejeta Conservancy in Kenya.
It was fully understandable, but it stopped our programme and, based on the experience we have now, you know, that was most likely not the right decision.
In Kenya, one female became infertile.
The other was too physically weak to breed.
In 2014, two of the remaining rhinos died in captivity, Ieaving a total of just five.
But there might still be a chance to stop the northern white rhino from disappearing from the planet for ever.
In California, scientists are trying to achieve in the lab what hasn't been possible in the zoo.
In this batch we have boxes of tubes and this tube here contains stem cells of the northern white rhino.
These stem cells were made from northern white rhino skin.
So they can become any cell of the body? Any cell of the body.
So in that small sample lies potentially More than a million cells.
And the future of the northern white rhino.
It's as simple as that, really, isn't it? Absolutely.
It's extraordinary.
Professor Jeanne Loring saw how stem cells could be used to save endangered species.
If we can make gametes from those cells, we can then take the sperm from one animal, an animal that's already dead, and eggs from another animal and make an entirely new individual.
An embryo would be implanted into a surrogate animal, the closely related southern white rhino.
The contents of this freezer are now part of a new multi-million-dollar effort to engineer northern white rhinos into existence within ten years.
Professor Loring and Professor Hildebrandt are working with San Diego Zoo and Dvur Kralove Zoo on the rescue plan.
The San Diego Zoo put dramatic resources in this rescue programme which wasn't seen before.
What we hope to achieve is that with this new approach, we can establish a new population of healthy northern white rhinos which then can mate natural-wise in the future.
But trying to bring back a species after it has gone extinct is fraught with uncertainty.
SHE EXHALES Despite immense efforts by zoos over decades, the northern white rhino is slipping away.
It's impossible not to get emotional, setting eyes on one of the last five remaining northern white rhinos.
The factors that led to the situation are complex and we have learned from our mistakes and what we might do differently now, given the chance.
But the hard truth is, we failed this species.
And if we fail with such a charismatic, popular animal .
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then what hope is there for other species, the thousands of other species that are threatened or endangered? The public's relationship with zoos has remained intact since this elephant house opened in Copenhagen Zoo more than a century ago.
But can zoos survive for another century? As it becomes more and more evident that many of the big animals that are the standard stars of zoos should not be in captivity for scientific reasons, that these animals are not thriving and cannot thrive, I think that the public will react in similar ways to the way they've reacted to the revelations about what was happening in SeaWorld.
I never even thought that they would go extinct 20 years ago, but now I'm certain that they will.
There are a lot of people today who say that zoos should shut down.
What do you think? I think those arguments of zoos being part of a problem and using animals and having massive welfare issues and not educating the public and not doing conservation, was true in the '40s, '50s, '60s and - shame on us - probably in the '70s and early '80s as well.
But genuinely, in the last 10 or 15 years, the world's changed and a lot of zoos have woken up to that and a lot of zoos are run now by people like me who passionately understand this, understand the arguments and we're trying to make a difference.
Throughout their history, zoos have adapted and grown and changed, and it's evident in the architecture of any zoo you look at.
I mean, this used to be the only enclosure for an adult elephant throughout the winter months back in the '60s.
Clearly, zoos have moved on.
This is Copenhagen's newest indoor enclosure for elephants, but are zoos changing enough? The zoo of the future, you'd have a lot of binoculars around the place, because your elephants will be right away on the other side and your chimpanzees would be high in a tree up there, five storeys up.
You'd need your binoculars.
That's the kind of zoo.
It's not what you'd call a zoo now.
RON KAGAN: There is a bright future for zoos, as long as zoos are totally committed to continuing to do research so that we understand what animals need, and that if we can't meet those needs, that we don't keep them.
So, in light of what the science is now telling us, are zoos willing to reappraise their fundamental roles as zoological and conservation organisations? The potential for zoos to educate about how we can interact with wildlife responsibly is enormous, but to reach the goal many scientists speak of would require substantial change.
The question now is how much zoos and we, the public, want that change to happen.
'A visit to the zoo has been a staple of family life for more than a century.
' A lot of us will remember the experience of seeing our first wild animal at the zoo as a child.
But is it time that zoos took a long, hard look at what they do? Zoos, if they stay as they are, inevitably will become extinct.
The public will just stop going to them.
I'm Liz Bonnin.
I've studied and worked in zoos, and I've observed just how intelligent animals can be.
Chase and tickle, he wants to chase and tickle with you now.
I want to chase and tickle with you too! But the more science is revealing about animals, the more difficult questions are being raised about why and how animals are kept in zoos.
Why are zoos still keeping elephants now that we know captivity can halve their life expectancy? To us it just became more and more clear that there was no there was no way to really make this work.
We want to be able to sleep at night.
Did captivity drive one of SeaWorld's orcas to kill his trainer? There is no evidence whatsoever that there is any mental aberration that is a result of living in a zoological park.
Why do so many zoo animals exhibit behaviours that are hardly seen in the wild? It does indicate that something is not right.
Is the battle to save endangered animals one that zoos can simply never win? We feel like janitors of the human culture.
We're trying to clean this mess up.
I want to ultimately find out if zoos need to change, to serve animals and humans better.
Or if they should be consigned to history.
A day out at the zoo, in Copenhagen.
In 2014, the zoo offered families an educational experience that some might find disturbing.
A two-year-old giraffe called Marius was culled, then dissected in front of them and fed to the lions.
What happened here lifted the lid on a practice few other zoos embrace so publicly.
Today I'm here to see it happen again.
Copenhagen Zoo has culled another animal.
This time it's a sable antelope.
How was she culled? What method did you use? She was shot with a rifle and you can see, if you want to, that she was shot right in the brain here.
And obviously, this is not a very enjoyable part of our job, but the key here is to do it so the animals have no idea what's coming and it has to be swift and efficient.
The culling of Marius triggered a global storm of protest.
In the firing line was Bengt Holst, director of research at the zoo.
Bengt, were you surprised by the reaction, by the backlash that you got because of the culling of Marius? Yes, very much indeed, and that's because we have done this, we have used this concept for more than 30 years here in the zoo, and we have done it with lions and with bears and leopards and antelopes and a lot of different animals, not with giraffes until now.
But it was really strange because we have never had this reaction before.
It may seem cruel, but culling has come about with the modernisation of zoos.
In the 19th century, when zoos began, most of the animals were taken from the wild.
Zoos would order animals for spring time, you know, because there was a new season and you'd bring them in and if they survived the summer, that was great, but if not, you'd just order some more next year.
Since the 1980s, zoos have aimed to develop a more positive relationship with the natural world.
Today it's much more conservation-minded.
It's ethically wrong to take all animals in from the wild, so we strive at being self-sustaining with as many animals as ever possible.
Now, more than 90% of the animals in zoos are born in captivity.
And around 90% of all species kept are not endangered in the wild.
Animals are carefully paired across zoos around the world to avoid in-breeding and to ensure genetic diversity.
But there is a consequence.
If you want to do serious breeding with animals, where you go for a healthy population far into the future, then you cannot avoid having, at some stage, if they breed well, a surplus.
That's because zoos can't breed just the animals they need to maintain a sustainable population.
You cannot go into a shop and buy three males and four females, for example, if that's what you need for your population.
You have to let them breed and you cannot predict what is the sex ratio.
At Copenhagen, surplus animals are also produced because the zoo takes a particular approach to animal welfare.
This particular animal is considered surplus to the programme, in the sense that her genes are already represented fairly well through numerous of her siblings.
The parents of this antelope, just like Marius's parents, were not paired in the international breeding programme.
Instead, Copenhagen decided to allow them to breed, rather than use methods to stop them, as other zoos do.
Why cull, as opposed to using contraceptives? Because by using contraceptives, you take away the breeding behaviour from the animals.
I think it's very important that we give the animals an opportunity to perform as much natural behaviour as ever possible.
And breeding behaviour is a big part of that natural behaviour.
If you take away that part, you have a welfare problem.
You reduce their welfare.
Before considering culling, zoos look at moving surplus animals to other zoos.
But space is limited, and priority is given to housing animals that are valuable to the breeding programmes.
This sort of proves that there are no surplus animals.
Everything has a role to play.
As controversial as Copenhagen's policy is, perhaps what's most surprising is how openly it's carried out here.
It's not known how many other zoos take the same approach to breeding, but it's estimated that between 3,000-5,000 healthy animals are culled by European zoos every year.
I would say in general, it is actually pretty common, but many zoos are not so open about it.
Some are doing it in disguise.
When Marius the giraffe hit the headlines, Copenhagen says it was criticised by other zoos.
We got attacks from other zoos, also in Europe.
Zoos that practise culling, or? Yes, some zoos that practise culling.
Does this mean that the zoos that were culling, but had attacked you, were saying you shouldn't have made it public, you shouldn't have engaged in the conversation? Some even said that you should have done it without Keep it behind the scenes and then don't mention it at all.
But I think it's not the way forward.
The journey zoos are on from the less-enlightened days of the past has reached a critical point.
The ever-growing human population means the wild has shrunk, with species disappearing faster than ever.
And science has moved on in leaps and bounds in its understanding of animals.
But are zoos adapting with the times? If you peel it all back, and you look at, say, London Zoo in 1828 - and all the other zoos throughout the 19th century - they all had big animals, showy animals, colourful animals, mainly from Africa or from Asia.
The typical zoo today has got exactly the same collections.
They have not moved on from that.
Zoos tell us that the welfare of their animals is at the heart of what they do.
But is it? Zoos have certainly published dozens of scientific papers about their animals.
But all that you can find, all these studies carried out by various zoos around the world, it's not always easy to talk to zoos about some of this research.
So it's hard to judge whether they're really keeping up with the latest scientific insights into animal needs.
At least, in most cases.
There is one zoo that's been quite keen to talk to us about their work and the stickier issues surrounding the welfare of captive animals.
ARCHIVE: 'A day at the zoo.
'The Detroit Zoological Park ranks with the finest in the world.
' Opened in 1928, Detroit Zoo kept the same animals most other zoos did - including elephants, a star attraction.
I've heard people say, "Oh, they haven't got an elephant in that zoo, "can't be any good.
" And if your zoo isn't popular because it doesn't have the animals that the public wants to see, they'll probably have to close the doors.
So we have to educate the public.
I'm visiting the zoo to find out about a novel approach to animal welfare, a vision that's raising a question for all zoos.
This place is taking a long, hard look at the scientific evidence to determine what animals it should keep and what it shouldn't.
The zoo's director, Ron Kagan, wants to show me why, when it came to elephants, he broke with 150 years of zoological tradition.
This used to be the indoor enclosure for Detroit's two Asian elephants.
Now, notice, there is more room for people I was going to say! .
.
than there is for elephants.
I didn't want to be smart about it, but how come there's more room for the people? Because zoos, in the beginning, were thinking a little bit more about people than they were about animals.
When they lived here, both elephants developed arthritis and chronic foot problems.
Many captive elephants have major problems with their feet because they're not walking enough and they're not walking on the right material.
The Michigan climate exacerbated the problem of not giving the elephants enough space.
When we had particularly long, harsh winters, and the elephants had to stay indoors for long periods of time, we knew that wasn't good for them.
To us, it just became more and more clear that there was no way to really make this work.
We want to be able to sleep at night.
In 2004, Detroit announced it was moving its elephants to a sanctuary.
There were people that said, oh, your attendance is going to drop and this is going to hurt revenue and it's going to We said, you know, we don't think that's right.
But we're just not prepared to knowingly keep animals that we don't think are doing well.
At the time, the zoo had just under a million visitors a year.
Now, it gets almost one and a half million.
The reaction from the American Association of Zoos and Aquariums The reaction from the American Association of Zoos and Aquariums who wanted the elephants moved to another zoo was less positive.
I lost my AAZA professional membership.
But what was their explanation for that? The explanation was that I had discussed this publicly.
I'm struggling with that.
Well Why are they so guarded? Because, as is often the case in a profession, people don't like dealing with complex ethical issues in a public forum.
And that was very unsettling for a lot of people in the zoo world.
But Ron was determined to push on with a radical rethink of what a zoo should be.
Instead of going, well, a good zoo must have elephants and rhinos and tigers and lions, you go, a good zoo must have animals that it knows can thrive and it should not have animals that can't thrive.
Detroit Zoo could see their own elephants were not thriving.
But assessing the welfare of captive elephants around the globe requires a more systematic approach.
And that's where science comes in.
Zoos have what are called stud books for most of the animals they keep - records of their genealogical background as well as births, deaths, transfers and imports of animals.
No-one really knew how well the European zoo population of elephants were doing until scientists studied these records.
And what they found was disturbing.
The most significant revelation was how long the elephants in European zoos were living.
It turned out captive-born female Asian elephants - the majority of the zoo population - were living 19 years on average.
Scientists wanted to benchmark this against the wild.
We looked to the nearest thing, which was timber camps in Burma.
And they've got a very good, equivalent stud book for their population.
And we're by no means saying that that is an ideal environment for elephants.
It's hard, they get worked hard.
But even with all that, we find that they were living till they were about 40.
So at least double what we were seeing in zoos.
It really raised a massive red flag that something is not right in the way that zoos are keeping elephants.
The research was published and a backlash began.
From zoos, it was on the whole quite negative and hostile.
And there was a reaction to discrediting us, rather than looking at their practices and the welfare of their elephants so that something could be done about it.
So why are zoos still keeping elephants? It's breakfast time at Twycross Zoo in Warwickshire.
Three of these female Asian elephants were brought here from timber camps in the 1980s.
The latest addition to the herd is two years old.
The zoo's director, Sharon Redrobe, is happy to discuss what the science is revealing about elephants in captivity.
The data is showing that elephants are dying at a much earlier age in captivity in zoos.
So how does one react to that as a zoo director? It's clearly not good enough in zoos at the moment.
The challenge with elephants is that they live, they should live, a very long time.
So any changes we make now won't be seen for 30, 40 years.
But we do know that we used to feed them a lot of cake, for goodness' sake, and they used to get really bad teeth, then they used to get very aggressive and people would shoot them.
This zoo allows the elephants to make choices, rather than directly handling them, as many zoo keepers still do.
According to the science, two risk factors limit the life spans of elephants in captivity - stress and obesity.
What will be really interesting is to see things like, baby Escher when she grows up, will she have arthritis? I really hope not, because we've changed the flooring, we've changed their diets.
So now we don't have fat elephants.
By establishing how elephants are faring in captivity with empirical evidence, scientists have helped to raise the ambition of some zoos.
I think this generation of elephants have suffered, and you can see that in the scientific data.
We can see it.
It's a shame, shame on us.
But the next thing is what we're going to do about it.
And the next generation needs to be protected, and we learn from the past.
The Government has told British zoos they must improve the welfare of their elephants by 2021, or risk having to phase them out.
I think the jury's still out in terms of whether enough will be done, because I think the changes needed are probably so big.
I'm very sceptical as to whether that will happen in this time period.
Science is giving zoos a new tool to help assess the needs of their animals.
A method of determining why animals often behave differently in zoos than in the wild.
Something that was poorly understood by those who first kept animals, like this.
Now, when this was built in the 1920s, it was a really revolutionary kind of big space.
Which is shocking when you think about it, but it was a long time ago.
And in those days, the animals were simply behind bars.
This far from adequate space was home to the zoo's polar bears.
When I've seen some of the early footage, I've seen as many as a dozen polar bears.
Now, the interesting thing to remember - and sometimes people don't know this when they go to zoos - is that obviously there's some animals that are very social, like elephants.
Primates, most primates.
Polar bears are not, so you normally would never see more than two together, except if it's a mother and cubs.
So this must have been a very tricky thing to manage back then.
This overcrowded environment may well have affected the way the polar bears behaved.
I'm sure there was a lot of stereotypy, but nobody was monitoring that or measuring that in the old days.
This is stereotypic behaviour, abnormal and repetitive with no obvious purpose.
Animals still are developing stereotypic behaviour, so it's not just a bygone era.
It's a modern phenomenon that is still an issue.
And I do think it does indicate that something's not right with the environment, and those animals aren't getting what they need.
Stereotypic behaviour is hardly ever seen in the wild, but it's often seen in zoos.
A 2004 Oxford University study reported that around 80% of carnivores performed stereotypic behaviour in captivity.
I'm on my way to meet one of the scientists who gathered data on abnormal behaviour in captive animals to find out what the root causes might be.
What she found fundamentally challenged the way zoos keep and manage animals.
This is the Belle Isle Zoo in Detroit, which opened in 1895.
It once housed one of the species most prone to stereotypic behaviour, polar bears.
Ever since she studied zoology, Professor Georgia Mason has been fascinated by stereotypic behaviour.
I was learning all about how animal behaviour has evolved and how evolution has shaped animals to be really efficient.
And then, in captivity, you'd see all this extravagant, wasteful pacing and head bobbing.
These animals should just be relaxing.
This is the life of Riley.
They've got everything they need.
Professor Mason investigated why animals display this behaviour, which many scientists believe is linked to stress and could reflect psychological damage.
It made me think, these things aren't arbitrary.
They're obviously reflecting something about the animal's natural biology, so let's see if we can tell what that is.
Professor Mason compared how much time carnivores in zoos spent pacing with how far they range over time in the wild.
There was a striking correlation.
We found that species that naturally have large home ranges and species that travel a relatively long way each day, they're the ones most at risk of this behaviour in captivity.
The species most at risk was the polar bear, which has the largest home range of all land mammals - sometimes over 250,000 square kilometres.
When Professor Mason came to publish her paper, she challenged zoos to fundamentally improve the way they keep wide-ranging carnivores or phase them out.
That really put the cat amongst the pigeons.
Why do you think it was so incendiary? I actually don't know! Because there's lots of conversations within the zoo community about, strategically, which species should they prioritise? Should it be the endangered ones, should it be the ones it's easiest to keep well? Should it be the ones that most inspire the public? I mean, it's a fascinating debate.
It is.
And as part of that conversation, I would think you should be allowed to say, let's not keep these.
Not because it's impossible to keep them well, but because it requires knowledge that we don't have yet, or resources that could be better spent on something else.
Among the theme parks of Orlando in Florida, one zoological institution is struggling to persuade the public that it's meeting the needs of some of the world's largest animals.
TV NEWS: 'This is SeaWorld.
'The atmosphere is part zoo, part circus.
' SeaWorld has displayed killer whales since 1964, but it's now mired in controversy after a documentary called Blackfish alleged that captivity severely compromises their welfare.
The film Blackfish examined the events leading up to the fatal attack on a trainer by a male orca, here at SeaWorld Orlando.
Like many people, I was moved by what I saw.
The footage and the accounts from ex-trainers were compelling, and SeaWorld chose not to take part in the film.
I went as far as calling for it to be shut down on Twitter.
Now, SeaWorld have decided to talk to me today, and I really want to hear their side of the story.
Can science cut through the heated debate about the welfare of SeaWorld's orcas? Dr Chris Dold is SeaWorld's head vet.
He's going to show me the orca that killed his trainer.
Oh, I think I can see Look at that! So this is Tilikum? So this is Tilikum, right here.
How would you describe Tilikum? The most impressive animal in a zoological park, anywhere.
During a performance in 2010, Tilikum pulled his trainer, Dawn Brancheau, into the pool.
PHONE CALL: Within minutes, she had drowned.
Why do you think Tilikum attacked and killed Dawn? It's a question that's been asked, and in the question right there, it's a mischaracterisation of what happened.
This was not an attack, this was a terrible accident.
And an accident that impacted all of us deeply.
What happened? If it wasn't an attack, what exactly happened? An accident, truly.
One of the things that we work with our whales on is how humans and whales safely interact, right? Tilikum is different from the rest of our group of whales in that those sorts of normal, safe working behaviours were not taught to him.
Did the constraints of captivity contribute to Tilikum's behaviour that day? A 2012 study tracked a wild orca that travelled almost 9,400 kilometres in 42 days, nonstop.
How far can they travel in any one day? We'd see them pass our field camp and then we'd find out, 24 hours later, that they were 100 miles away.
They've gone through millennia of evolution.
Natural selection is what it is.
These animals have to move those distances to stay healthy.
Three trainers have been killed by captive orcas.
Tilikum has been involved in the deaths of two.
One before SeaWorld owned him, as well as the death of a man who entered his pool in Orlando.
According to SeaWorld's records, their orcas have injured trainers 12 times between 1988 and 2009.
This is an animal that ranges 100 miles a day, that travels not only to hunt, that communicates vast distances and is now in captivity.
Could this somehow contribute to a psychosis that leads to an animal killing not one, but two, but three individuals? The key thing is that Tilikum's behaviour - and there is no evidence whatsoever that there is any mental aberration that is a result of living in a zoological park or otherwise.
How do we know, when we don't actually have the research to show that? Is it conjecture, is it opinions? I think it's experiential evidence.
But is experiential good enough? Does any of this not have to rely on strong, empirical, scientific data? I think, over time, deep, empirical evidence will come forward.
Since Dawn Brancheau's death, action by a federal safety agency has stopped SeaWorld's trainers from being in the water during orca shows.
The question of whether killer whales might suffer psychological problems in captivity remains unanswered.
Scientists have investigated the cognitive capacities of dolphins, members of the cetacean family that includes orcas.
So this is one of the dolphins in front of the mirror, and you can see he's doing something called contingency checking.
He's making strange motions with his head to see if the image in the mirror is doing the same thing, and once he figures out that that's him in the mirror, then he goes on to use the mirror to explore himself in a lot of different ways.
So here's one example of that.
What do I look like upside down? It's a beautiful thing to watch.
And here's another dolphin fooled into believing that he has been given a mark under his pectoral fin and he's actually moving in a way in front of the reflective surface to see if there is an actual mark there.
It's extraordinary behaviour, it's compelling behaviour.
What this research tells us is that these beings have a sense of self.
They have a sense of who they are, what they look like and what their circumstances are.
So they know it was them yesterday, it's them today in the mirror, and it will be them tomorrow.
But science has yet to determine whether animals with complex cognitive capabilities suffer more, or in fact can adapt well, in captivity.
SeaWorld have their own view.
With the relative intelligence of cetaceans, it's actually, I think, what has allowed them to thrive so well in zoological settings.
And that's because, unlike some species of animals that just want to be by themselves and want nothing to do with humans, cetaceans clearly work readily with us.
And that's why we're able to provide such remarkable care for them.
The welfare of SeaWorld's orcas is under scrutiny like never before.
The California Coastal Commission approved SeaWorld's multi-million-dollar plan to expand its pools in San Diego.
But only if it stops breeding orcas there.
SeaWorld is challenging the ruling.
Do you envisage a time in the future where, with scientific evidence, you will choose not to keep killer whales in captivity any more? And keep other animals that have been shown to thrive through hard, empirical data? No.
I don't imagine that future, because we know our killer whales are thriving in the habitats where we keep them now.
SeaWorld has published a paper showing their orcas Iive as long as those in the wild.
Independent scientists are working on rebuttals, due to concerns about the methodology they used.
We've sort of reached the point where we just conclude as a society that there are no solid data that they can thrive in captivity.
It's all hand-waving from SeaWorld.
And so, we need to conclude that this isn't appropriate any more.
This is a species that isn't suitable for a zoo life.
Detroit Zoo believes it's found a way to enable its polar bears to thrive, but it's come at a hefty price.
They call it the Arctic Ring of Life - now home to just two polar bears, a male and a female.
At over 1.
6 acres, this enclosure is more than eight times the size of the old one.
But that's not its only key feature.
We believe the bears have to have some choices.
Yeah.
The habitat was designed There are two separate habitats, so they have opportunities to choose to be with another bear or without another bear.
Choice is an important part of a polar bear's natural behaviour as it moves around in the wild.
They're making lots of decisions.
They're choosing where to be based on prey abundance, mate availability, that kind of thing.
So it could be that really the solution for these animals in zoos is to allow them to make more decisions, give them more control, give them more day to day variability.
So rather than thinking, oh, no, we have to give them giant enclosures, the solutions could be more imaginative.
You see how the hill goes up? Yeah.
For bears, one of their most important senses to them is their sense of smell.
And so there's nothing blocking the wind when they go to the top of the exhibit.
According to a 2013 study by three American zoos, polar bears with stimulating environments and a view out of the enclosure show significantly less stereotypic behaviour.
Detroit Zoo say they see less stereotypic behaviour with their bears here than in their old enclosure.
This hasn't been quantified yet, but it is encouraging, considering animals like these are not suitable for release back into the wild.
It's highly unlikely they could survive.
So what can we say about the lives of these polar bears now? I would say, I believe she has a pretty good life.
That is so subjective.
That's just me.
I 've known her since she was born and I could be totally wrong.
But I believe she has the things that are meaningful.
This enclosure cost around $16 million to design and build.
At that kind of price, trying to meet the welfare needs of animals like polar bears forces zoos to make hard choices.
If you want quality, you have to give up on quantity.
You can't do every animal.
You can't have a postage stamp collection and expect to be able to have all the animals thrive.
The emphasis on animals thriving in captivity, not just surviving, may sound obvious, but it could revolutionise the zoo world.
If zoos really did put welfare at the very top, how would zoos be different? Well, you'd have fewer animals in each zoo.
You'd have fewer species in each zoo.
You'd have species in a climate that is appropriate.
And there's no question in my mind, that's where things are going.
I think you'll see fewer zoos with polar bears, fewer zoos with elephants, fewer zoos with gorillas.
And different ones will have different expertise.
And you know, that means that you might have to travel further if you want to go see a particular type of animal.
But there's no reason that every city should have a zoo that each one has zebras, giraffes, elephants, rhinos, etc.
Around zoos, the world is changing.
We're living through an unprecedented mass extinction crisis.
The rapid rise of the human population has dramatically reshaped the natural environment, destroying habitats at an alarming rate.
Dr Jane Goodall has seen how the wild has shrunk since she first studied chimpanzees in Tanzania in 1960.
And, for her, it makes a compelling case for zoos.
If the world is beautiful, and like it was when I went first to Africa, that's where all chimps should be.
But it's not.
I've seen so many places where there's logging coming closer, chimpanzees under threat.
And, quite honestly, when you go to a really good zoo which has a big outside enclosure, then you think, well, actually, if I was a chimp, I'd probably rather be here than out in all these dangerous situations in the wild.
Because of human impacts, species are disappearing at a rate 100 times faster than would be expected.
Zoos are saying that saving animals is their fundamental role.
At about the same time that television and film were taking over from the simple task that zoos had of showing you what a polar bear looks like, zoos then changed their direction and said, we are conservation centres.
This is our primary purpose, is conservation.
If we weren't breeding and maintaining animals, then some of these animals would be going rapidly extinct in the wild, and we wouldn't have this ark principle, this repository of animals, to ever put them back.
This is the role now of zoos.
It's changed radically since the '50s and the '60s, of just show and tell wild animals.
We are now part of the solution.
I don't think this is a sustainable claim for zoos to say that they're conservation centres.
It's a very thin, slender little column that they've built for themselves to stand on.
When it comes to breeding endangered species, zoos have gained vast amounts of expertise and knowledge, thanks to years of dedication.
Take the effort to save the California condor, one of the world's most endangered birds.
I'm keen to help out, but Mike Clark from LA Zoo has got other ideas.
You don't want me to hold the eggs for you? You're not on the permit, the federal permit to touch the eggs.
You have to have a federal permit to handle them? Oh, yeah.
In the 1980s, there were just 22 California condors Ieft in the wild.
The last of the species were brought into a zoo, and the captive breeding programme began.
So this would be egg LA-10-15.
Each egg is closely monitored.
There you go.
Oh, look at that, that's fantastic.
Look at that.
As the chicks are reared, contact with zoo keepers is limited.
This is a condor hand puppet, something we make right here.
The hand-reared chicks are fed by puppets.
Some birds showed no fear of humans when they were released, so the keepers had to adapt.
So what would this puppet do, other than just drop the food? The chicks can get kind of rambunctious and become abusive towards the puppet, because there's no consequences.
And so the puppet would actually have to move them away, Iike, you're not going to do that, that's not the way to behave.
Over three decades, zoos have perfected the method of breeding condors.
But successfully reintroducing them into the wild is a much greater challenge.
This is Hopper Mountain, north of Los Angeles, one of the sites where captive-born condors are released.
I'm with Estelle Sandhaus, a scientist from Santa Barbara Zoo.
'On the other side of this canyon is a historic nesting site, 'if only I could see it!' Gosh, it's really thrilling to see it.
Yeah, absolutely, absolutely.
God, she's gorgeous, isn't she? Yeah, she absolutely is.
It's amazing.
These mountains have been turned into a zoo of sorts.
The birds are constantly monitored because, without intensive management, the population would once again collapse.
The reason can be found at LA Zoo.
'This is 360, a sick condor brought in from the wild.
' He's a beaut.
'What happened to him reveals just how much human behaviour is 'undermining this reintroduction programme.
' This is a ventral view of the whole body and if you look carefully, you can see a high density object, that's metal, and that is the piece of lead that was poisoning him.
Across the region, hunters often use lead ammunition, which shatters inside the animals they hunt.
As scavengers, condors feed on the carcases and can easily be poisoned.
These are additional radiographs of 360 from June of 2010, June of 2012 and then 2015, like you see here.
So, actually he's been in three times for lead poisoning.
How old is he? Ten.
Ten years old and he's been in three times.
Yeah.
'360 was lucky.
'Vets removed this latest particle, 'but 59 others have died from lead poisoning 'since the reintroduction programme began.
' Look at that wing span.
I mean, there's no question when you see such a spectacular species, of course it should be protected.
Of course we can't let it go extinct, but what's the point of releasing it again if all the threats persist? I think that with these birds out here, we are able to capture people's hearts and minds and really advocate for them and ask folks to change their habits.
After more than 30 years and more than $40 million, there are now 228 California condors in the wild.
With the California condor, zoos have achieved the near impossible.
I mean, it's taken a huge amount of effort and money and intensive, relentless interventions to keep the birds just about alive out here, but the battle they've been fighting for decades now can't be won without changing human behaviour.
This is not just a job to save the species.
This is a human problem and we feel like janitors of the human culture.
We're trying to clean this mess up.
Until the culture changes and the lead is out of their food source, me and the people I work with will be treating leads until we retire, and probably beyond.
When it comes to conservation, British zoos claim that at least 3% of their expenditure goes towards projects in the field.
Figures like this are hard to quantify across the zoo world, but zoos say their conservation role is not just about funding.
We can use animals as ambassadors, we can use them for education and that's really important.
We have half a million people a year seeing these elephants and that's our opportunity to hook them into valuing them, seeing what they're like for real, smelling them, which you don't get from the TV, and then valuing wildlife is how we're going to change the future, cos it's this generation of humans that needs to change their behaviour to save the wild.
The goal of zoos to educate the public about the importance of conservation is laudable, but so far, their success has not been scientifically proven.
The claim that seeing elephants in the zoo will turn you into a conservationist is a completely false claim.
There's no evidence at all that seeing animals in zoos changes people's opinion.
As our cities continue to grow, along with our insatiable consumption of the planet's resources, the destruction of wild habitats is speeding up.
Surveying this seemingly unstoppable tide is conservation scientist Dr Sarah Bexell.
As a veteran of captive breeding programmes, she has strong personal views.
I definitely for a long time have been worried that we are sending the wrong message to the general public, that you can drive your SUV and you can have as many children as you want.
Don't worry, we'll save a couple of the cute ones for you.
Science is going to save the animals we deem worthy of saving.
For the past 25 years, Sarah has worked on some of the world's biggest reintroduction programmes - the golden lion tamarin in Brazil, the black-footed ferret in the American West, the giant panda programme in China.
Like others, this project is succeeding in breeding animals, but struggling to build a self-sustaining population in the wild.
Around 400 pandas have been bred in captivity, but just five have been released and only three survive.
All things considered, a huge amount of money has been spent on the captive breeding programme for pandas and considering so few, although precious individuals, have been reintroduced, has it been worth it? Is it worth it? Ah.
I mean, we've learned a lot, absolutely.
Filled volumes of journals and textbooks and But we have not made significant headway in terms of conservation.
So, I mean, I guess right now, we would almost have to say it has been quite a failure and even though many of these projects even were considered successful for short periods of time, they've lost ground.
And should we continue them? Right now, I'm feeling no, because I'm really worried that it's sending the wrong message to humanity.
It's giving humanity false hopes.
Captive breeding appeared to be a conservation panacea, promising to curb extinctions and replenish the wild.
But as humanity's destruction of habitat gathers pace, Sarah believes zoos need to level with us about what saving endangered species would really require.
I think we need to be brutally honest with the world, that science is not just going to clean up the mess for you all.
We all have to get behind this, we all have to be a part of the solution.
Perhaps the most controversial of all zoo breeding programmes is that of the northern white rhino.
The effort to save this species from extinction began in the mid-1970s as the persecution of these animals by humans increased dramatically.
No animal is safe from poachers.
There were three more white rhino until a few months ago.
Then poachers butchered them at point blank range to steal their valuable horns.
As northern white rhinos were relentlessly hunted over decades, the future of the species came to depend entirely on the ability of zoos to breed them, and that proved far from easy.
The species is now extinct in the wild and unravelling the reasons why reveals just how many aspects of the breeding programme fell short of expectations.
This is the Dvur Kralove Zoo in the Czech Republic.
I'm here to see a very special animal.
This is Nabire.
'Nabire is one of the last five northern white rhinos on Earth.
' Can we say hello, with an apple? Moment.
Little bit back, no.
Yeah, pull everything back.
She might chew on my cuff.
Take it like this.
Just like that? OK, so not flat hand.
OK, put that inside.
OK, I can put that inside.
I can give you an apple, beauty.
Oh, OK, here we go.
Perfect.
Here we go.
Ohhh! HE SPEAKS CZECH Nabire is of breeding age, but unfortunately she's now infertile.
The history of the captive population is a story of extinction taking place in slow motion.
Since 1975, when northern white rhinos were first brought to this zoo, just four calves had been born in captivity.
For many years, the zoo didn't know how to maximise the chances of breeding.
We started to understand if you have, you know, all the animals at one place for a long time, it somehow blocks the, let's say, breeding appetites.
As they failed to breed, the female rhinos were becoming infertile.
When there were just two fertile females left, a decision was made to attempt artificial insemination.
All our hope is on her and we will try to get her pregnant as soon as possible.
But the attempt failed.
Failing with the artificial insemination doesn't mean the programme failed.
We were quite optimistic that we would achieve a pregnancy over time, if we would get full support for such assist reproduction programme.
The zoo devised a new strategy.
The last two fertile females were sent to the Ol Pejeta Conservancy in Kenya.
It was fully understandable, but it stopped our programme and, based on the experience we have now, you know, that was most likely not the right decision.
In Kenya, one female became infertile.
The other was too physically weak to breed.
In 2014, two of the remaining rhinos died in captivity, Ieaving a total of just five.
But there might still be a chance to stop the northern white rhino from disappearing from the planet for ever.
In California, scientists are trying to achieve in the lab what hasn't been possible in the zoo.
In this batch we have boxes of tubes and this tube here contains stem cells of the northern white rhino.
These stem cells were made from northern white rhino skin.
So they can become any cell of the body? Any cell of the body.
So in that small sample lies potentially More than a million cells.
And the future of the northern white rhino.
It's as simple as that, really, isn't it? Absolutely.
It's extraordinary.
Professor Jeanne Loring saw how stem cells could be used to save endangered species.
If we can make gametes from those cells, we can then take the sperm from one animal, an animal that's already dead, and eggs from another animal and make an entirely new individual.
An embryo would be implanted into a surrogate animal, the closely related southern white rhino.
The contents of this freezer are now part of a new multi-million-dollar effort to engineer northern white rhinos into existence within ten years.
Professor Loring and Professor Hildebrandt are working with San Diego Zoo and Dvur Kralove Zoo on the rescue plan.
The San Diego Zoo put dramatic resources in this rescue programme which wasn't seen before.
What we hope to achieve is that with this new approach, we can establish a new population of healthy northern white rhinos which then can mate natural-wise in the future.
But trying to bring back a species after it has gone extinct is fraught with uncertainty.
SHE EXHALES Despite immense efforts by zoos over decades, the northern white rhino is slipping away.
It's impossible not to get emotional, setting eyes on one of the last five remaining northern white rhinos.
The factors that led to the situation are complex and we have learned from our mistakes and what we might do differently now, given the chance.
But the hard truth is, we failed this species.
And if we fail with such a charismatic, popular animal .
.
then what hope is there for other species, the thousands of other species that are threatened or endangered? The public's relationship with zoos has remained intact since this elephant house opened in Copenhagen Zoo more than a century ago.
But can zoos survive for another century? As it becomes more and more evident that many of the big animals that are the standard stars of zoos should not be in captivity for scientific reasons, that these animals are not thriving and cannot thrive, I think that the public will react in similar ways to the way they've reacted to the revelations about what was happening in SeaWorld.
I never even thought that they would go extinct 20 years ago, but now I'm certain that they will.
There are a lot of people today who say that zoos should shut down.
What do you think? I think those arguments of zoos being part of a problem and using animals and having massive welfare issues and not educating the public and not doing conservation, was true in the '40s, '50s, '60s and - shame on us - probably in the '70s and early '80s as well.
But genuinely, in the last 10 or 15 years, the world's changed and a lot of zoos have woken up to that and a lot of zoos are run now by people like me who passionately understand this, understand the arguments and we're trying to make a difference.
Throughout their history, zoos have adapted and grown and changed, and it's evident in the architecture of any zoo you look at.
I mean, this used to be the only enclosure for an adult elephant throughout the winter months back in the '60s.
Clearly, zoos have moved on.
This is Copenhagen's newest indoor enclosure for elephants, but are zoos changing enough? The zoo of the future, you'd have a lot of binoculars around the place, because your elephants will be right away on the other side and your chimpanzees would be high in a tree up there, five storeys up.
You'd need your binoculars.
That's the kind of zoo.
It's not what you'd call a zoo now.
RON KAGAN: There is a bright future for zoos, as long as zoos are totally committed to continuing to do research so that we understand what animals need, and that if we can't meet those needs, that we don't keep them.
So, in light of what the science is now telling us, are zoos willing to reappraise their fundamental roles as zoological and conservation organisations? The potential for zoos to educate about how we can interact with wildlife responsibly is enormous, but to reach the goal many scientists speak of would require substantial change.
The question now is how much zoos and we, the public, want that change to happen.