Harpies are among the largest birds of prey in the world and are threatened with extinction. Vito, a male from Nuremberg Zoo, was sent to South America to care for offspring.
Harpies are among the largest birds of prey on earth. They are at home in Latin America, but are losing more and more of their habitat. Vito hatched in Nuremberg Zoo in 1991 – and is now expected to provide offspring in the home of the harpies.
It was the biggest journey in Vito’s life: From Europe, he flew across the Atlantic, Venezuela, and Colombia to Ecuador. With pure wing power, the would be about 9.500 kilometers had been too far – the male harpy covered the distance in the cargo hold of an airplane. Joep Hendriks met him at the airport in Quito and drove him to Otavalo, a small town two hours north of Quito. Here Hendriks runs Parque de Condor, Vito’s new home.
On a day at the end of October, Hendriks gives a tour of his bird park. Born in the Netherlands, he is in his mid-60s, wears a hat like Indiana Jones, aviator glasses and a leather shoulder bag with cut-up day-old chicks as snacks for the birds of prey. Hendriks stops in front of Vito’s aviary. It is located next to a hillside from which one can see for miles across a valley to a mountain range of the Andes. Vito sits in the back on a wooden beam in the shade.
As typical for harpies, Vito has a gray neck and white plumage on the abdomen. When excited, it erects its imposing head feathers like the spikes of a crown. "Normally he’s very trusting," Hendriks says. "Come! Come!" Vito screws his head forward a bit, but stays put. He is not here to delight. Vito has a mission: sire offspring to save his species from extinction.
The population shrinks threateningly
Harpies are among the largest birds of prey on earth. They are at home in Latin America, but are losing more and more of their habitat. They prefer to build their nests in very tall jungle trees such as kapok, which can grow up to 60 meters tall and are highly sought after by the timber industry. Harpies eat sloths, small monkeys and iguanas. When fully grown, they need almost a kilo of meat a day.
Due to the deforestation of large forest areas in the Amazon region, the supply of prey is shrinking; the harpies can no longer feed their young or themselves. Again and again they are hunted because of their beautiful feathers, shot out of curiosity or captured.
The population has been threateningly reduced in recent decades. Scientists can only estimate how many of the birds are still around. Some speak of 50.000, the World Conservation Union IUCN estimates that there are at least 100 of them.000, but now lists harpies as an endangered species. In El Salvador they are already extinct. Even in Paraguay and Argentina they were not seen again.
Breeding in the zoo for continued existence
Vito had never seen the home of his fellow species before his journey. He hatched in the Nuremberg Zoo in 1991 and has spent most of his avian life there. Even from northern Germany and the Netherlands visitors came to admire him, because even in zoos, the imposing birds are rare. There are only 17 in Europe and the USA, and around 180 in the rest of the world. This is also due to the lack of offspring: In the Nuremberg Zoo, for example, no harpy has been born for 20 years.
Vito in his new home in Ecuador. Here he lives now with harpy lady Olafa.
In 2018, at a congress in Brazil for the conservation of the species, it was decided to target the reproduction of the birds in zoos. Lorenzo von Fersen also gave a talk at the conference. He is the curator for research and species conservation at the Nuremberg Zoo. He says: "The protections in the harpy’s natural habitat are not enough. We need to build a ‘back-up population’."In this way, it would be possible to reintroduce the animals in a protected area in case of emergency and prevent extinction in the wild.
One strategy suggested: mate more animals from different zoos. Especially in Latin America, zoos often keep only one harpy, more often males than females.
Came to mate
This is where Vito comes in. In the Nuremberg Zoo there was no suitable mate for him: The only female in the park was already taken – and so was his sister. So Vito spent his life in an aviary of his own. Keeping harpies alone is no problem for them; except for the mating season, they also live alone in the wild. But offspring cannot be sired in this way.
Lorenzo von Fersen and his colleague Joep Hendriks came up with a plan to pair Vito with Olafa – a harpy lady from Parque de Condor and also single. The seemingly obvious option of pairing Olafa with a male from Brazil proved complicated. Several times Joep Hendriks tried this. But zoos in Latin America are often privately owned and see each other as competition, explains Lorenz von Fersen. Cooperations, as they occur in the USA and Europe, are rare.
So Hendriks and Von Fersen decided on an intercontinental collaboration between Ecuador and Germany. For almost two years they organized Vito’s move. Hundreds of hours of work, applications by the zoos and the German Embassy to the authorities were needed before Ecuador’s Ministry of Agriculture agreed to the entry. However, this promise was conditional on many specifications. Thus, the animal had to spend several weeks in quarantine and undergo several medical check-ups before departure and after arrival respectively.
On 11. August 2020 it could finally go. Vito was caught with a net and put into his transport box. The custom-made wooden box was about twice the height and length of a large moving box, with air holes and a system through which drinking water could be refilled from the outside. Several information stickers, harpy photos and the national flags of Germany and Ecuador were stuck on the box, above the lettering "Unidad para la conservacion" – United for conservation.
Vito was very relaxed the whole time, says Lorenzo von Fersen. And he himself? "I wasn’t sad to see Vito leave us," he says, "more glad that he doesn’t have to squat around alone anymore now."Von Fersen took Vito all the way to the sprinter that would take the bird to the airport in Amsterdam, and wished the bird "good flight" and "goodbye" in Spanish.
Female Olafa eating. The claws of the females are larger than a bear’s claw and can effortlessly grab prey of several dozen kilos and drag it away. They can also be dangerous for a male.
New home, new company
Arriving at Parque de Condor, Vito had to spend three weeks in the quarantine station before he could enter his aviary. About 120 birds are kept permanently in the bird park: The smallest is the pygmy owl, the largest the Andean condor, Ecuador’s national animal. Joep Hendriks is a teacher by training, but has kept falcons since childhood. In 2007 he opened the park in Otavalo. On the one hand, it is a reception and infirmary for injured birds, which usually stay only for a short time. In addition, Hendriks takes in birds that can no longer be released into the wild due to serious injuries or that have been donated from other zoos or private breedings. If animals are only imprinted, i.e. already accustomed to humans as chicks, it is unlikely that they will survive in the wild. This is also the case with Vito.
Hendriks gives all animals a name. Mostly this one has to do with her origin. This is the name of one of the giant sea eagles from Russia Trotsky. Vito was also renamed. "Vito sure sounds like a mobster," Hendriks says. Officially, Vito is now Lorenzo, a tribute to the behavioral biologist Von Fersen in Nuremberg, Germany.
Hendriks remembers well how the newcomer from Germany first entered his new aviary: reserved, but not afraid. Olafa, on the other hand, had been completely out of his mind. "If it had been up to her, they would have mated right away," Hendriks believes. "She saw Vito and begged." "There! She does it again!", shouts Hendriks and points to the aviary. Olafa staggers toward Vito with wings outstretched, making high, short calls like a seagull screaming in staccato.
The strongest birds of prey in the world
In contrast to Vito, Olafa is rather difficult to handle and often aggressive towards humans. That’s also why they thought twice before putting Vito in with her, Hendriks says. Female harpies, as is often the case with birds of prey, are significantly larger and heavier than the males. They weigh up to nine kilograms, Vito weighed about five kilograms at the last weighing in Germany.
The claws of the females are larger than a bear’s claw and can easily grab prey weighing several dozen kilograms and drag it away. This earned the species the title as the strongest birds of prey in the world. It has happened that female harpies in captivity have killed the male because they didn’t get along, Hendriks says.
If Olafa really wanted to take out her bad mood on Vito, he could easily escape her, because Olafa cannot fly. As a chick she fell out of the nest. To this day, it draws the right wing behind it like a bride draws her veil. The beak was dislocated at that time and still has to be filed regularly so that she can close it. In everyday life, both should cause her little trouble. Even in the wild, harpies rarely fly, according to Joep Hendriks. "Most of the day they sit in the tree and only move around for two things. First: to feed. Second: for sex."
Both are literally served to the birds in their aviary. It is designed to be barrier-free for Olafa, with stairs leading up to the platforms. Only sometimes does it look as if Olafa wants to fly off – then she jumps forward with her wings spread, but immediately comes staggering back to her feet.
The accident did not harm their fertility. Olafa came to Ecuador from a breeding program in Panama and is considered the most successful breeding female in the world. 16 young birds she has hatched in the past. All were released into the wild in Panama, but were killed by humans shortly thereafter. With Viro Olafa could dare a new start, because with 33 years she is still young enough for the mating. Unfortunately there is one problem: Vito does not want to mate. As Olafa walks toward him that day, dredging, he looks back impassively. This has been going on for a long time, Hendriks reports. "Olafa has desire, Vito has headache."
The strange behavior of sexually mature harpies
Vito’s mating inertia is not new. Vito had already given a female harpy the cold shoulder in Germany. At that time he had moved from Nuremberg for some time in the bird park Walsrode. They had naturally hoped that things would go a little better with the experienced female Olafa, says Lorenzo von Fersen from the zoo in Nuremberg. "But you also have to be honest, harpies are a bit odd when it comes to mating." In the choice of a partner they are demanding. Basically understandable, because they live most of the time alone, but form partnerships for life – always meet with the same animal for mating. So it’s a matter of luck to bring two harpies together, says Von Fersen. "It may simply be that they don’t harmonize."
Whether this is the case with Vito and Olafa, can not yet be said exactly. Everything about mating and reproduction seems to work leisurely for harpies. Only after about four years harpies are sexually mature. Once they have found a mate in the wild, it is not uncommon for it to take two years for the offspring to arrive. Even if two eggs are laid, only one is hatched at a time. The young animal remains in the care of the mother for years, sometimes only after six years looking for its own territory.
There are more challenges in getting them to reproduce: "We know incredibly little about harpies," says Von Fersen. Because the animals live high up in the trees in their natural habitat, he says, it’s difficult to observe them. Only a few projects do this so far. Little is known about the mating behavior and reproduction of harpies in particular, he said, and research is progressing slowly. "Until recently, for example, we thought that harpies had no courtship behavior at all."Then they saw a pair of harpies in Nuremberg beak – a sign of affection.
Basically, you have to watch the animals around the clock, says von Fersen. The goal must be that the animals feel as comfortable as possible. At the moment, the zoos promote the reproduction of their harpy pairs in a kind of try-and-error procedure. In the Nuremberg zoo they tried out with higher branches and heated rods. Evita, Vito’s sister, and her male Jorge were not placed directly together, but separated by a plexiglass screen. So they could see, hear and get used to each other. "When we observed them offering branches to each other – also courtship behavior – we removed the window," says Von Fersen. In fact, Evita laid a fertilized egg soon after, incubated for over 50 days. However, the embryo died in December, a few days before hatching.