Of okapis and men: Antwerp Zoo helps preserve endangered species


Behind the scenes at Antwerp Zoo is a fascinating world of laboratories, genetic records and animal poo, as scientists and care managers work to protect some of the world’s most endangered species

Make me a match

The okapi waits patiently as its caretaker steps out of the enclosure to get some more breakfast snacks. Noticing a freshly cut branch, the animal sticks out its long, flexible tongue and tries to sneak a mouthful of leaves.

At first glance, the slender okapi looks nothing like its closest living relative, the giraffe. It’s no larger than a horse, and its neck and legs are normal length. Look closely, and you might take it for a hybrid, its striped legs borrowed from a zebra, its caramel-coloured torso that of an antelope.

While the enclosures at Antwerp Zoo are being enlarged and renovated, the park is home to three okapis, down from the usual five to 10. There are an estimated 10,000 to 35,000 of them left in the wild, but all of them live in the equatorial forests of the Congo, a country ravaged by years of internal conflict and environmental degradation.

“Today we are at the forefront of the fight to preserve this stunning animal,” says Ilse Segers, the zoo’s spokesperson. “The okapi is an essential part of our zoo’s history. We were the first in the world to have one on display.”

Okapi family tree

The zoo’s first okapi, Buta, arrived in 1919, after a sea voyage of several weeks. The nine-month-old proved to be an instant sensation with the crowds; most people have never seen or heard of the animal. Within a month, however, the calf grew much weaker and eventually died.

“Back then nobody was thinking about conservation,” explains Sander Hofman, the park’s animal care manager. “When a zoo wanted to add a new species to its collection, it would capture the animal in the wild, bring it to Europe and display it in a cage. And when the animal died, the park would just get a new one.”

I know of every single okapi outside of Africa

- Antwerp Zoo care manager Sander Hofman

This all changed in the 1970s and ‘80s, he continues, with the emerging consensus that African wildlife couldn’t cope with the increased human pressure. “Instead of competing for the most unique assortment of animals,” says Hofman, “European zoos decided to co-operate in creating a stable back-up population for the most threatened species.”

Today, Antwerp Zoo no longer exports animals out of Africa. Instead, it breeds the ones it has with animals from other European zoos. “We know we need to work together to allow these species to thrive,” Hofman says.

The pairing of two captive okapis anywhere outside of Africa begins with Hofman (pictured above), who is responsible for maintaining an international record that contains genetic information on every okapi that’s ever lived in a zoo, starting with Buta. The programme was established in the 1950s to prevent inbreeding and maximise genetic diversity. Since the 1970s, Antwerp Zoo has been in charge of the initiative.

The park also maintains records for the Eurasian black vulture, the bonobo and the golden-headed lion tamarin, among others. The books look inconspicuous –essentially spread sheets bound in a plastic cover – but they play a crucial role in the protection of the okapi. “I know of every single okapi outside of Africa,” says Hofman.

For the animals, not the humans

Although he feels attached to the okapi, he doesn’t let it stop him from seeing the bigger picture. “If another park asks me to send the animals to them, I will do so, even if they’re as symbolic to us as the okapi,” he says. “We’re doing it for the benefit of the species, not our own.”

To ensure that the animals remain “as okapi as possible”, Hofman consults with Philippe Helsen, the zoo’s geneticist, who tells him if a given male and female are the most optimal mates. “The idea is to keep the DNA of all the earlier generations surviving throughout the next,” says Hofman.

The gap between humans and wildlife is getting bigger and bigger

- Sander Hofman

Because Helsen studies the genetic makeup in a lab, he often doesn’t actually see the animals. This, Hofman says, can lead to some awkward situations. Once a male turned out to be considerably shorter than the female, so Hofman and his team had to construct a tiny hill from which the okapi could mount his mate.

“This goes to show how difficult it is to combine theory with reality,” notes Hofman.

In Africa, Antwerp Zoo has partnered up with local organisations on a variety of conservation projects. The zoos that keep the okapi provide about 25-35% of the running costs of protecting the last remaining areas where the animal still lives in the Congo.

But the species is designated as threatened, and conservation efforts have had little effect, due to the violent situation in the country and the habits of the okapi itself. “It’s an incredibly shy animal,” Hofman says. “There is no footage of the okapi in the Congo, and even the rangers who work in the field only get to see it on rare occasions.”

Species gap

In the ideal world, he continues, zoos wouldn’t be necessary. “But we don’t live in an ideal world. The gap between humans and wildlife is getting bigger and bigger. Most of the public doesn’t even know what an okapi is, so how can we convince them that this is an animal worth protecting?”

In addition to creating a stable back-up population that could one day be returned to the wild, Hofman and his team are trying to build awareness around the animal. “This brings us to the fundamental question,” he says. “Why do we have animals in zoos in the first place? My answer is that we need to strengthen the connection between people and nature. If it weren’t for zoos, the okapi would probably be gone by now.”

You start with poo, which seems like nothing, and suddenly you have answers to all your research questions

- Antwerp geneticist Philippe Helsen

No one knows how many okapis remain in the wild. Instead of attempting to count the elusive creatures, the Congolese rangers, some of whom are employed by Antwerp Zoo, collect their droppings and send them to Europe for analysis.

In the lab, Helsen (pictured below) sifts through the samples and studies the genetic makeup, including insect and plant remains. “It’s fun,” he says. “You start with poo, which seems like nothing, and suddenly you have answers to all your research questions.”

Not all samples come from abroad. “We collect DNA from the droppings of our own animals to determine their sex and exact species,” Helsen says. “If the method proves effective, we ask rangers to send us more samples of droppings, so we can figure out how many individuals are left in the wild, where they live and how they move from place to place. This is less obtrusive than trying to collect DNA from actual animals.”

Forging a link

Helsen’s lab is hidden under an artificial mountain in a remote corner of the zoo. Visitors don’t have access, which the geneticist says is a shame; he’d like more people to learn about the zoo’s scientific work.

“Zoos are a means of forging a link between animals and humans,” he says. “Once you make that connection, you begin to realise how important it is to preserve these species.”

Zoo animals, he continues, play a vital role in conservation efforts. “Thanks to captive populations, we know how many offspring certain species have and how long they live. We need this information to assess whether their wildlife population is threatened or viable.”

Thanks to captive populations, we know how many offspring certain species have and how long they live

- Philippe Helsen

In addition to sponsoring okapi conservation efforts, Antwerp Zoo also funds the construction of safe corridors for Asian elephants in India and leads a research project into endangered apes in Cameroon. It also manages De Zegge nature reserve in Antwerp province, home to the only population of grass snakes in Flanders.

Helsen can spend all day talking about these efforts, but his true passion is birds. “I’ve been in love with them since I was six years old,” he says. “My uncles were birdwatchers. They would conduct counts every month to see whether some birds were doing better or worse than the previous year.”

Peering through the microscope for hours at a time, he no longer gets to observe animals in the wild, but the love for birds extends into his work. As we leave the lab and head to a nearby enclosure, he starts talking about a project that’s proven to be one of Antwerp Zoo’s most successful.

Perched on a dead tree, the bird couple observe their surroundings with stoic patience. The male stretches his wings, which reach upwards of three metres across. The Eurasian black vulture makes for a formidable creature.


The birds used to be a common in Europe, spreading from Spain to Turkey, and even as far as China. “Then a century ago, the central part of their distribution simply disappeared,” Helsen says. “France, Italy, Bulgaria, Romania – all gone. We suspect it had to do with poaching and land given over to agriculture.”

A few years ago, a group of bird enthusiasts in France became determined to bring the vultures back. “Why? Because it’s not natural that they disappeared,” Helsen says. “The population crash was caused by human interference.”

Antwerp Zoo has experience in breeding vultures, so it offered to help. As a geneticist, Helsen took it upon himself to ensure the purest genetic makeup. “I would say ‘put that male and that female together, and you will preserve the most genes’. But that didn’t work; the birds did not want to mate.”

Vultures, it turns out, are picky when it comes to choosing a partner. So the Antwerp Zoo created a dating site at the Planckendael animal park in Mechelen. “We bring young vultures from across Europe there to choose their own mates,” Helsen explains. “When couples form, they are sent back to the zoo, and their offspring are released into the wild. We’re sort of like matchmakers.”

Thanks to the birds provided by Antwerp Zoo, local organisations have released more than 100 vultures in France. They now look to repeat the same success in Bulgaria.

Photos: Bart Van der Moeren

Antwerp Zoo

Antwerp Zoo is one of the oldest and best-conserved zoos in the world. The zoo buildings and gardens are registered as protected Flemish heritage.
Kai-Mook - In 2009, Kai-Mook, the first baby elephant born on Belgian soil, dominated national and international headlines for weeks.
Founding - The Zoo was established by former Antwerp mayor Jans Frans Loos. After visiting Amsterdam’s zoo, he decided it was time for Antwerp to get its own.
Short - In colloquial Flemish speech, Antwerp Zoo has long gone by the simple name “De Zoo”.
1 843

Zoo opens


surface area in hectares

5 000